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On April 8, 2024, a total solar eclipse will be visible across much of the central and northeastern United States, as well as parts of Mexico and Canada.

Whether you are traveling to the path of the total eclipse or will be able to step outside and watch the eclipse where you live, here's everything you need to know, including what to expect, how to watch safely, and how to engage in scientific observations and discovery with NASA.

What Are Solar Eclipses?

Solar eclipses occur when the Sun, the Moon, and Earth align. For this alignment to happen, two things need to be true. First, the Moon needs to be in the new moon phase, which is when the Moon’s orbit brings it between Earth and the Sun. Second, eclipses can only happen during eclipse seasons, which last about 34 days and occur just shy of every six months. An eclipse season is the time period when the Sun, the Moon, and Earth can line up on the same plane as Earth's orbit during a new or full moon. If a new moon happens during an eclipse season, the shadow cast by the Moon will land on Earth, resulting in a solar eclipse. Most of the time, because the Moon’s orbit is slightly tilted, the Moon’s shadow falls above or below Earth, and we don't get a solar eclipse.

Not all solar eclipses look the same. The distance between the Sun, the Moon, and Earth plays an important role in what we see during a solar eclipse. Even though the Moon is much smaller than the Sun (about 400 times smaller in diameter), the Sun and Moon look about the same size from Earth. This is because the Sun is about 400 times farther away than the Moon. But as the Moon travels its elliptical orbit around Earth, its size appears slightly larger when it is closer to Earth and slightly smaller when it is farther from Earth. This contributes to the different kinds of solar eclipses you might have heard about. For example:

• During a total solar eclipse, the Moon is closer to Earth in its orbit and appears larger, completely blocking the Sun's disk. This allows viewers in the path of totality to see the Sun’s corona, which is usually obscured by the bright light of the Sun’s surface.


This image of a total solar eclipse was captured on Aug. 21, 2017 from Madras, Oregon. Image credit: NASA/Aubrey Gemignani | › Full image and caption

• An annular solar eclipse occurs when the Sun, Moon, and Earth are properly aligned, but the Moon is farther away in its orbit, so it does not completely cover the Sun's disk from our perspective. Annular eclipses are notable for the "ring of fire," a thin ring of the Sun’s disk that's still visible around the Moon during annularity. The name annular eclipse comes from the world of mathematics, where a ring shape is known as an annulus.


On Jan. 4, 2017, the Hinode satellite captured these breathtaking images of an annular solar eclipse. Image credit: Hinode/XRT | › Full image and caption

• Partial eclipses can happen for two reasons. First, viewers outside the path of totality during a total solar eclipse – or the path of annularity during an annular eclipse – will see only part of the Sun’s surface covered by the Moon. The other time a partial eclipse can occur is when the Moon is nearly above or below Earth in its orbit so only part of the Moon’s shadow falls on Earth. In this case, only part of the Sun’s surface will appear covered by the Moon.


The Sun appears partially eclipsed in this series of photos taken from NASA’s Johnson Space Center in Houston on Aug. 21, 2017. Image credit: NASA/Noah Moran | › Full image and caption

How to Watch the Upcoming Solar Eclipse

First, an important safety note: Do not look directly at the Sun or view any part of the partial solar eclipse without certified eclipse glasses or a solar filter. Read more below about when you can safely view the total solar eclipse without eclipse glasses or a solar filter. Visit the NASA Eclipse website for more information on safe eclipse viewing.

When following proper safety guidelines, witnessing an eclipse is an unparalleled experience. Many “eclipse chasers” have been known to travel the world to see solar eclipses. Here's what to expect on April 8, 2024:

The start time and visibility of the eclipse will depend on your location. You can use this map to find detailed eclipse information, including the start time, by clicking on your location.

The eclipse begins when the edge of the Moon first crosses in front of the disk of the Sun. This is called a partial eclipse and might look as if a bite has been taken out of the Sun.

It is important to keep your eclipse glasses on during all parts of the partial solar eclipse. The visible part of the Sun is tens of thousands of times brighter than what you see during totality. You can also use a pinhole camera to view the eclipse.

An approximately 115-mile-wide strip known as the path of totality is where the shadow of the Moon, or umbra, will fall on Earth. Inside this path, totality will be visible starting about 65 to 75 minutes after the eclipse begins.

If you are in the path of totality, it is safe to take off your eclipse glasses and look at the total eclipse only during totality. Be sure to put your glasses back on before the total phase ends and the surface of the Sun becomes visible again. Your viewing location during the eclipse will determine how long you can see the eclipse in totality. In the U.S., viewers can expect to see 3.5 to 5.5 minutes of totality.

After totality ends, a partial eclipse will continue for 60 to 80 minutes, ending when the edge of the Moon moves off of the disk of the Sun.

For more information about the start of the partial eclipse, the start and duration of totality, and the percentage of the Sun eclipsed outside the path of totality, find your location on this eclipse map.

On April 8, NASA Television will host a live broadcast featuring views from telescopes along the path of totality.

What Solar Eclipses Mean for Science

Solar eclipses provide a unique opportunity for scientists to study the Sun and Earth from land, air, and space, plus allow the public to engage in citizen science!

Scientists measure incoming solar radiation, also known as insolation, to better understand Earth’s radiation budget – the energy emitted, reflected, and absorbed by our planet. Just as clouds block sunlight and reduce insolation, eclipses create a similar phenomenon, providing a great opportunity to study how increased cloud cover can impact weather and climate.

Solar eclipses can also help scientists study solar radiation in general and the structure of the Sun. On a typical day, the bright surface of the Sun, called the photosphere, is the only part of the Sun we can see. During a total solar eclipse, the photosphere is completely blocked by the Moon, leaving the outer atmosphere of the Sun (corona) and the thin lower atmosphere (chromosphere) visible. Studying these regions of the Sun’s atmosphere can help scientists understand solar radiation, why the corona is hotter than the photosphere, and the process by which the Sun sends a steady stream of material and radiation into space. Annular solar eclipses provide opportunities for scientists to practice their observation methods so that they'll be ready when a total solar eclipse comes around.

Citizen scientists can get involved in collecting data and participating in the scientific process, too, through NASA’s GLOBE program. During the eclipse, anyone in the path of the eclipse and in partial eclipse areas can act as citizen scientists by measuring temperature and cloud cover data and report it using the GLOBE Observer app to help further the study of how eclipses affect Earth’s atmosphere.

Visit NASA's Eclipse Science page to learn more about the many ways scientists are using the eclipse to improve their understanding of Earth, the Moon, and the Sun.

Solar Eclipse Lessons and Projects

Use these standards-aligned lessons and related activities to get your students excited about the eclipse and the science that will be conducted during the eclipse.

• 
  Student Project

  How to Make a Pinhole Camera

  Learn how to make your very own pinhole camera to safely see a solar eclipse in action from anywhere the eclipse is visible, partial or full!

  Subject Science

  Grades K-12

  Time < 30 mins

• 
  Lesson

  Moon Phases

  Students learn about the phases of the Moon by acting them out. In 30 minutes, they will act out one complete, 30-day, Moon cycle.

  Subject Science

  Grades 1-6

  Time 30-60 mins

• 
  Math Problem

  Model a Solar Eclipse

  Students use simple materials to model a partial, annular, and total solar eclipse.

  Subject Science

  Grades 1-8

  Time 30-60 mins

• 
  Lesson

  Measuring Solar Energy During an Eclipse

  Students use mobile devices to measure the impact a solar eclipse has on the energy received at Earth’s surface.

  Subject Math

  Grades 4-7

  Time 1-2 hrs

• 
  Lesson

  Modeling the Earth-Moon System

  Students learn about scale models and distance by creating a classroom-size Earth-Moon system.

  Subject Science

  Grades 6-8

  Time 30-60 mins

• 
  Math Problem

  Epic Eclipse

  Students use the mathematical constant pi to approximate the area of land covered by the Moon’s shadow during the eclipse.

  Subject Math

  Grades 6-12

  Time < 30 mins

• 
  Math Problem

  Eclipsing Enigma

  Students use pi to figure out how much of the Sun’s disk will be covered by the Moon during an eclipse and whether it’s a total or annular eclipse.

  Subject Math

  Grades 7-12

  Time < 30 mins

• 
  Mobile App

  NASA GLOBE Observer App

  Students can become citizen scientists and collect data for NASA’s GLOBE Program using this app available for iOS and Android devices.

Explore More

Eclipse Info

• NASA Eclipses Website
• Calendar of Past and Upcoming Eclipses
• Downloadable Eclipse Map

Eclipse Safety

• Eclipse Safety
• Suppliers of Safe Solar Filters & Viewers

Interactives

• Interactive Eclipse Simulation

Citizen Science

• NASA GLOBE App

Facts & Figures

• NASA Eclipse Science
• Earth’s Radiation Budget

TAGS: Solar Eclipse, Eclipse, Annular Eclipse, K-12 Education, Lessons, Classroom Resources, STEM Resources

• 

  ABOUT THE AUTHOR

  Lyle Tavernier, Educational Technology Specialist, NASA-JPL Education Office

  Lyle Tavernier is an educational technology specialist at NASA's Jet Propulsion Laboratory. When he’s not busy working in the areas of distance learning and instructional technology, you might find him running with his dog, cooking or planning his next trip.

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NASA is launching a spacecraft in October 2023 to visit the asteroid Psyche, a metal-rich asteroid. The mission with the same name, Psyche, will study the asteroid, which is located in the main asteroid belt between Mars and Jupiter, to learn more about our solar system, including the core of our own planet.

Read more to find out what we will learn from the Psyche mission. Get to know the science behind the mission and follow along in the classroom using STEM teaching and learning resources from NASA.

Why It's Important

Asteroids are thought to be rocky remnants that were left over from the early formation of our solar system about 4.6 billion years ago. Of the more than 1.3 million known asteroids in our solar system, Psyche’s metallic composition makes it unique to study. Ground-based observations indicate that Psyche is a giant metal-rich asteroid about one-sixteenth the diameter of Earth’s Moon and shaped like a potato. Scientists believe it might be the partial nickel-iron core of a shattered planetesimal – a small world the size of a city that is the first building block of a planet. Asteroid Psyche could offer scientists a close look at the deep interiors of planets like Earth, Mercury, Venus, and Mars, which are hidden beneath layers of mantle and crust.

We can’t see or measure Earth’s core directly – it is more than 1,800 miles (3,000 kilometers) below the surface and we have only been able to drill about 7.5 miles (12 kilometers) deep with current technology. The pressure at Earth’s core measures about three million times the pressure of the atmosphere at the surface, and the temperature of Earth’s core is about 9,000 degrees Fahrenheit (5,000 degrees Celsius), so even if we could get science instruments there, the hostile conditions would make operations practically impossible. The Psyche asteroid may provide information that will allow us to better understand Earth’s core, including its composition and how it was created. The asteroid is the only known place in our solar system where scientists might be able to examine the metal from the core of a planetesimal.

The Psyche mission's science goals are to understand a previously unexplored building block of planet formation (iron cores); to explore a new type of world; and to look inside terrestrial planets, including Earth, by directly examining the interior of one of these planetary building blocks, which otherwise could not be seen. The science objectives that will help scientists meet these goals include determining if asteroid Psyche is actually leftover core material, measuring its composition, and understanding the relative age of Psyche's surface regions. The mission will also study whether small metal-rich bodies include the same light elements that are hypothesized to exist in Earth's core, determine if Psyche was formed under similar or different conditions than Earth's core, and characterize Psyche's surface features.

How It Will Work

The Psyche mission will launch on a SpaceX Falcon Heavy rocket. Psyche’s solar arrays are designed to work in low-light conditions because the spacecraft will be operating hundreds of millions of miles from the Sun. The twin plus-sign shaped arrays will deploy and latch into place about an hour after launch from Earth in a process that will take seven minutes for each wing. With the arrays fully deployed, the spacecraft will be about the size of a singles tennis court. The spacecraft’s distance from the Sun will determine the amount of power it can generate. At Earth, the arrays will be able to generate 21 kilowatts, which is enough electricity to power three average U.S. homes. While at asteroid Psyche, the arrays will produce about two kilowatts, which is a little more than what is needed to power a hair dryer.

The spacecraft will rely on the launch vehicle’s large chemical rocket engines to blast off the launchpad and escape Earth’s gravity, but once in space, the Psyche spacecraft will travel using solar-electric propulsion. Solar-electric propulsion uses electricity from the solar arrays to power the spacecraft’s journey to asteroid Psyche. For fuel, Psyche will carry tanks full of xenon, the same neutral gas used in car headlights and plasma TVs. The spacecraft’s four thrusters – only one of which will be on at any time – will use electromagnetic fields to accelerate and expel charged atoms, or ions, of that xenon. As those ions are expelled, they will create thrust that gently propels Psyche through space, emitting blue beams of ionized xenon. The thrust will be so gentle that it will exert about the same amount of pressure you’d feel holding three quarters in your hand, but it’s enough to accelerate Psyche through deep space. You can read more about ion propulsion in this Teachable Moment.

The spacecraft, which will travel 2.2 billion miles (3.6 billion kilometers) over nearly 6 years to reach its destination, will also use the gravity of Mars to increase its speed and to set its trajectory, or path, to intersect with asteroid Psyche’s orbit around the Sun. It will do this by entering and leaving the gravitational field of Mars, stealing just a little bit of kinetic energy from Mars’ orbital motion and adding it to its own. This slingshot move will save propellant, time, and expense by providing a trajectory change and speed boost without using any of the spacecraft’s onboard fuel.

Upon arrival at Psyche, the spacecraft will spend 26 months making observations and collecting data as it orbits the asteroid at different altitudes. Unlike many objects in the solar system that rotate like a spinning top, the asteroid Psyche rotates on its side, like a wheel. Mission planning teams had to take this unique characteristic into account in planning the spacecraft's orbits. The different orbits will provide scientists with ideal lighting for the spacecraft's cameras and they will enable the mission to observe the asteroid using different scientific instruments onboard.

The spacecraft will map and study Psyche using a multispectral imager, a gamma-ray and neutron spectrometer, a magnetometer, and a radio instrument (for gravity measurement). During its cruise to the asteroid, the spacecraft will also test a new laser communication technology called Deep Space Optical Communication, which encodes data in photons at near-infrared wavelengths instead of radio waves. Using light instead of radio allows the spacecraft to send more data back and forth at a faster rate.

Follow Along

Psyche is scheduled to launch no sooner than October 5, 2023 from Kennedy Space Center in Florida. Tune in to watch the launch on NASA TV.

Visit the mission website to follow along as data are returned and explore the latest news, images, and updates about this mysterious world.

Teach It

The Psyche mission is a great opportunity to engage students with hands-on learning opportunities. Explore these lessons and resources to get students excited about the STEM involved in the mission

Resources for Teachers

• 
  Collection

  Psyche Lessons for Educators

  Explore a collection of standards-aligned lessons related to NASA's Psyche mission.

• 
  Collection

  Asteroids Lessons for Educators

  Explore a collection of standards-aligned lessons all about asteroids and craters.

• 
  Article

  Teachable Moments: How NASA Studies and Tracks Asteroids Near and Far

  Studying the chemical and physical properties, as well as the location and motion of asteroids, is vital to helping us understand how the sun, planets and other solar system bodies came to be. This article explores how NASA studies and tracks asteroids.

• 
  Expert Talk

  Teaching Space With NASA: Tracking Asteroids

  In this educational talk, NASA experts will discuss how we track and study comets and asteroids. Plus, we'll answer your questions!

• 
  Article

  Teachable Moments: The Science Behind NASA's First Attempt at Redirecting an Asteroid

  Find out more about the historic first test, which could be used to defend our planet if a hazardous asteroid were discovered.

Activities for Students

• 
  Collection

  Psyche Activities for Students

  Explore projects, videos, slideshows, and games for students all about asteroids.

• 
  Collection

  Asteroids Activities for Students

  Explore projects, videos, slideshows, and games for students all about asteroids.

Explore More

Resources for Kids

Check out these related resources for kids from NASA Space Place:

• Article for Kids: Asteroid or Meteor: What's the Difference?
• Article for Kids: What Is an Asteroid?
• Article for Kids: Why Does the Moon Have Craters?
• Article for Kids: What Is an Impact Crater?

Websites

• Psyche Mission
• Asteroid Watch
• Center for Near-Earth Object Studies
• NASA Space Apps Challenge

Articles

• Psyche News Archive
• Articles: Asteroid News from JPL

Images

• Psyche Image Gallery

Videos

• Psyche Mission Video

Interactives

• Eyes on Asteroids

Printouts

• Print a 3D Model of the Psyche Spacecraft
• Create a Psyche Lego Model
• Create a Model of the Psyche Asteroid

TAGS: Teachers, Classroom, Lessons, Educators, K-12, Parents, Students, Resources, Asteroid TM, Psyche

• 

  ABOUT THE AUTHOR

  Anne Tapp, Professor of Teacher Education, Saginaw Valley State University

  Anne Tapp is a professor of teacher education at Saginaw Valley State University. In 2023, she served as an educator in residence with the K-12 Education team at NASA's Jet Propulsion Laboratory. Outside of writing and teaching, she enjoys serving as a volunteer for educational organizations, traveling, and gazing at the stars.

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Scientists may soon uncover new insights about some of the most mysterious phenomena in our universe with the help of the newly launched Euclid mission. Built and managed by the European Space Agency, Euclid will use a suite of instruments developed, in part, by NASA's Jet Propulsion Laboratory to explore the curious nature of dark energy and dark matter along with their role in the expansion and acceleration of our universe.

Read on to learn how the Euclid mission will probe these cosmological mysteries. Then, find out how to use demonstrations and models to help learners grasp these big ideas.

Why It’s Important

No greater question in our universe promotes wonder in scientists and non-scientists alike than that of the origin of our universe. The Euclid mission will allow scientists to study the nearly imperceptible cosmic components that may hold exciting answers to this question.

Edwin Hubble's observations of the expanding universe in the 1920s marked the beginnings of what's now known as the big-bang theory. We've since made monumental strides in determining when and how the big bang would have taken place by looking at what's known as cosmic background radiation using instruments such as COBE and WMAP in 1989 and 2001, respectively. However, there's one piece of Hubble's discovery that still has scientists stumped: our universe is not only expanding, but as scientists discovered in 1998, that expansion is also accelerating.

This side by side comparison shows a constant rate of expansion of the universe, represented by the expanding sphere on the left, and an accelerating rate of expansion of the universe, represented by the expanding sphere on the right. Each dot on the spheres represents a galaxy and shows how galaxies move apart from each other faster in the universe that has an accelerating rate of expansion. | Watch on YouTube

How can this be? It makes intuitive sense that, regardless of the immense force of the big bang that launched all matter across the known universe 13.8 billion years ago, that matter would eventually come to a rest and possibly even start to collapse. Instead, it's as if we've dropped a glass onto the ground and discovered that the shards are flying away from us faster and faster into perpetuity.

Scientists believe that answers may lie in two yet-to-be-understood factors of our universe: dark matter and dark energy. Dark matter is unlike the known matter we experience here on Earth, such as what's found on the periodic table. We can't actually see dark matter; we can only infer its presence. It has mass and therefore gravity, making it an attractive force capable of pulling things together. Amazingly, dark matter makes up roughly 27% of the known universe compared with the much more modest 5% of "normal matter" that we experience day to day. However, dark matter is extremely dilute throughout the universe with concentrations of 105 particles per cubic meter.

In opposition to the attractive force of dark matter, we have dark energy. Dark energy is a repulsive force and makes up roughly 68% of energy in the known universe. Scientists believe that the existence of dark energy and the amount of repulsion it displays compared with dark matter is what's causing our universe to not only expand, but also to expand faster and faster.

Dr. Jennifer Wiseman, a senior project scientist with the Hubble Space Telescope mission, explains how the mission has been helping scientists learn more about dark energy. Credit: NASA Goddard | Watch on YouTube

But to truly understand this mysterious force and how it interacts with both dark matter and normal matter, scientists will have to map barely detectable distortions of light traversing the universe, carefully measuring how that light changes over time and distance in every direction. As JPL Astrophysicist Jason Rhodes explains, “Dark energy has such a subtle effect that we need to survey billions of galaxies to adequately map it.”

And that's where Euclid comes in.

How It Works

The European Space Agency and NASA each contributed to the development of the Euclid mission, which launched from Cape Canaveral Space Force Station in Florida on July 1. The spacecraft consists of a 1.2-meter (48-inch) space telescope and two science instruments: an optical camera and a near-infrared camera that also serves as a spectrometer. These instruments will provide a treasure trove of data for scientists of numerous disciplines, ranging from exoplanet hunters to cosmologists.

As Gisella de Rosa at the Space Telescope Science Institute explains, “The ancillary science topics we will be able to study with Euclid range from the evolution of the objects we see in the sky today to detecting populations of galaxies and creating catalogs for astronomers. The data will serve the entire space community.”

The cameras aboard Euclid will operate at 530-920 nanometers (optical light) and at 920-2020 nanometers (near infrared) with each boasting more than 576 million and 65 million pixels, respectively. These cameras are capable of measuring the subtle changes to the light collected from celestial objects and can determine the distances to billions of galaxies across a survey of 15,000 square degrees – one-third of the entire sky.

Meanwhile, Euclid's spectrometer will collect even more detailed measurements of the distance to tens of millions of galaxies by looking at redshift. Redshift describes how wavelengths of light change ever so slightly as objects move away from us. It is a critical phenomenon for measuring the speed at which our universe is expanding. Similar to the way sound waves change as a result of the Doppler effect, wavelengths of light are compressed to shorter wavelengths (bluer) as something approaches you and extended to longer wavelengths (redder) as it moves away from you. As determined by a Nobel Prize winning team of astronomers, our universe isn’t just red-shifting over time, distant objects are becoming redder faster.

Euclid will measure these incredibly minuscule changes in wavelength for objects near and far, providing an accurate measurement of how the light has changed as a factor of time and distance and giving us a rate of acceleration of the universe. Furthermore, Euclid will be able to map the relative densities of dark matter and normal matter as they interact with dark energy, creating unevenly distributed pockets of more attractive forces. This will allow scientists to identify minute differences in where the universe is expanding by looking at the way that light is altered or "lensed."

The multi-dimensional maps created by Euclid – which will include depth and time in addition to the height and width of the sky – will inform a complementary mission already in development by NASA, the Nancy Grace Roman Space Telescope. Launching in 2026, this space telescope will look back in time with even greater detail, targeting areas of interest provided by Euclid. The telescope will use instruments with higher sensitivity and spatial resolution to peer deeper into redshifted and faint galaxies, building on the work of Euclid to look farther into the accelerating universe. As Caltech’s Gordon Squires describes it: “We’re trying to understand 90% of our entire universe. Both of these telescopes will provide essential data that will help us start to uncover these colossal mysteries.”

Teach It

The abstract concepts of the scope and origin of our universe and the unimaginable scale of cosmology can be difficult to communicate to learners. However, simple models and simulations can help make these topics more tangible. See below to find out how, plus explore more resources about our expanding universe.

Resources

• 
  Educator Guide

  Model the Expanding Universe

  Students learn about the role of dark energy and dark matter in the expansion of the universe, then make a model using balloons.

  Subject Science

  Grades 6-12

  Time 30-60 mins

• 
  Educator Guide

  How Do We See Dark Matter?

  Students will make observations of two containers and identify differences in content, justify their claims and make comparisons to dark matter observations.

  Subject Science

  Grades 6-12

  Time Less than 30 mins

• 
  Educator Guide

  Math of the Expanding Universe

  Students will learn about the expanding universe and the redshift of lightwaves, then perform their own calculations with a distant supernova.

  Subject Science

  Grades 9-12

  Time 30-60 mins

• 
  Collection

  ViewSpace: Dark Energy Videos

  Use this collection of short videos to introduce learners to the concept of dark energy.

• 
  Collection

  ViewSpace: Dark Matter Videos

  Use this collection of short videos to introduce learners to the concept of dark matter.

• 
  Science Briefing

  Hubble Constant Discrepancies: Implications for Our Expanding Universe

  Hear experts discuss how the rate of the universe is measured in different cosmological epochs and what the differences in those measures can tell us.

• 
  Game

  Roman Space Observer

  How many astrophysical objects can you catch?

Explore More

• Article for Kids: What Is a Supernova?
• Article for Kids: What Is Dark Matter?
• Article: What Is Dark Energy?
• Article: Gravitational Lensing - Shining a Light on Dark Matter
• Facts & Figures: Euclid Mission - NASA
• Facts & Figures: Nancy Grace Roman Space Telescope

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NASA's Universe of Learning materials are based upon work supported by NASA under award number NNX16AC65A to the Space Telescope Science Institute, working in partnership with Caltech/IPAC, Center for Astrophysics | Harvard & Smithsonian, and the Jet Propulsion Laboratory.

TAGS: K-12 Education, Teaching, Teachers, Educators, Resources, Universe, Dark Matter, Dark Energy, Euclid, Nancy Grace Roman Space Telescope, Universe of Learning

• 

  ABOUT THE AUTHOR

  Brandon Rodriguez, Educator Professional Development Specialist, NASA-JPL Education Office

  Brandon Rodriguez is the educator professional development specialist at NASA’s Jet Propulsion Laboratory. Outside of promoting STEM education, he enjoys reading philosophy, travel and speaking to your dog like it's a person.

In the News

What do "Star Wars," NASA's Dawn spacecraft and Newton's Laws of Motion have in common? An educational lesson that turns science fiction into science fact using spreadsheets – a powerful tool for developing the scientific models addressed in the Next Generation Science Standards. Keep reading to learn more and find out how to get students wielding the force.

Why It's Important

The TIE (Twin Ion Engine) fighter is a staple of the "Star Wars" universe. Darth Vader flew one in "A New Hope." Poe Dameron piloted one in "The Force Awakens." And many, many Imperial pilots met their fates in them. While the fictional TIE fighters in "Star Wars" flew a long time ago in a galaxy far, far away, ion engines are a reality in this galaxy today – and have a unique connection to NASA’s Jet Propulsion Laboratory.

Launched in 1998, the first spacecraft to use an ion engine was Deep Space 1, which flew by asteroid 9969 Braille and comet Borrelly. Fueled by the success of Deep Space 1, engineers at JPL set forth to develop the next spacecraft that would use ion propulsion. This mission, called Dawn, would take ion-powered spacecraft to the next level by allowing Dawn to go into orbit twice – around the two largest objects in the asteroid belt: Vesta and Ceres.

How It Works

Ion engines rely on two principles that Isaac Newton first described in 1687. First, a positively charged atom (ion) is pushed out of the engine at a high velocity. Newton’s Third Law of Motion states that for every action there is an equal and opposite reaction, so then a small force pushes back on the spacecraft in the opposite direction – forward! According to Newton’s Second Law of Motion, there is a relationship between the force (F) exerted on an object, its mass (m) and its acceleration (a). The equation F=ma describes that relationship and tells us that the small force applied to the spacecraft by the exiting atom provides a small amount of acceleration to the spacecraft. Push enough atoms out, and you'll get enough acceleration to really speed things up.

Why is It Important?

Compared with traditional chemical rockets, ion propulsion is faster, cheaper and safer:

• Faster: Spacecraft powered by ion engines can reach speeds of up to 90,000 meters per second (more than 201,000 mph!)
• Cheaper: When it comes to fuel efficiency, ion engines can reach more than 90 percent fuel efficiency, while chemical rockets are only about 35 percent efficient.
• Safer: Ion thrusters are fueled by inert gases. Most of them use xenon, which is a non-toxic, chemically inert (no risk of exploding), odorless, tasteless and colorless gas.

These properties make ion propulsion a very attractive solution when engineers are designing spacecraft. While not every spacecraft can use ion propulsion – some need greater rates of acceleration than ion propulsion can provide – the number and types of missions using these efficient engines is growing. In addition to being used on the Dawn spacecraft and communication satellites orbiting Earth, ion propulsion could be used to boost the International Space Station into higher orbits and will likely be a part of many future missions exploring our own solar system.

Teach It

Newton’s Laws of Motion are an important part of middle and high school physical science and are addressed specifically by the Next Generation Science Standards as well as Common Core Math standards. The lesson "Ion Propulsion: Using Spreadsheets to Model Additive Velocity" lets students study the relationship between force, mass and acceleration as described by Newton's Second Law as they develop spreadsheet models that apply those principles to real-world situations.

Educator Guides

• 
  Using Spreadsheets to Model Additive Velocity

  Students develop spreadsheet models that describe the relationship between the mass of a spacecraft, the force acting on the craft, and its acceleration.

  Grades 6-12

  Time 30-60 mins

• 
  Motion and Forces Lessons

  Get students wielding "the force" with these standards-aligned lessons all about motion and forces.

  Grades K-12

  Time Varies

Student Activities

• 
  Using the Force

  Stay on target, make a hovercraft, and explore more independent projects for students all about motion and forces.

  Grades K-12

  Time Varies

Explore More

• Website: Dawn Mission
  
• Blog: Dawn Journal
  
• Video: Crazy Engineering - Ion Propulsion
  
• Ion propulsion interactives
• Eyes on the Solar System: Dawn Mission Tour (scroll to "Solar System Tours" and click the "Dawn" link)

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This feature was originally published on May 3, 2016.

TAGS: May the Fourth, Star Wars Day, F=ma, ion propulsion, Dawn, Deep Space 1, lesson, classroom activity, NGSS, Common Core Math

• 

  ABOUT THE AUTHOR

  Lyle Tavernier, Educational Technology Specialist, NASA-JPL Education Office

  Lyle Tavernier is an educational technology specialist at NASA's Jet Propulsion Laboratory. When he’s not busy working in the areas of distance learning and instructional technology, you might find him running with his dog, cooking or planning his next trip.

Update: March 15, 2023 – The answers are here! Visit the NASA Pi Day Challenge page to view the illustrated answer keys for each problem.

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This year marks the 10th installment of the NASA Pi Day Challenge. Celebrated on March 14, Pi Day is the annual holiday that pays tribute to the mathematical constant pi – the number that results from dividing any circle's circumference by its diameter.

Every year, Pi Day gives us a reason to celebrate the mathematical wonder that helps NASA explore the universe and enjoy our favorite sweet and savory pies. Students can join in the fun once again by using pi to explore Earth and space themselves in the NASA Pi Day Challenge.

Read on to learn more about the science behind this year's challenge and find out how students can put their math mettle to the test to solve real problems faced by NASA scientists and engineers as we explore Earth, Mars, asteroids, and beyond!

How It Works

Dividing any circle’s circumference by its diameter gives you an answer of pi, which is usually rounded to 3.14. Because pi is an irrational number, its decimal representation goes on forever and never repeats. In 2022, mathematician Simon Plouffe discovered the formula to calculate any single digit of pi. In the same year, teams around the world used cloud computing technology to calculate pi to 100 trillion digits. But you might be surprised to learn that for space exploration, NASA uses far fewer digits of pi.

Here at NASA, we use pi to measure the area of telescope mirrors, determine the composition of asteroids, and calculate the volume of rock samples. But pi isn’t just used for exploring the cosmos. Since pi can be used to find the area or circumference of round objects and the volume or surface area of shapes like cylinders, cones, and spheres, it is useful in all sorts of ways. Transportation teams use pi when determining the size of new subway tunnels. Electricians can use pi when calculating the current or voltage passing through circuits. And you might even use pi to figure out how much fencing is needed around a circular school garden bed.

In the United States, March 14 can be written as 3.14, which is why that date was chosen for celebrating all things pi. In 2009, the U.S. House of Representatives passed a resolution officially designating March 14 as Pi Day and encouraging teachers and students to celebrate the day with activities that teach students about pi. And that's precisely what the NASA Pi Day Challenge is all about!

The Science Behind the 2023 NASA Pi Day Challenge

This 10th installment of the NASA Pi Day Challenge includes four noodle-nudgers that get students using pi to calculate the amount of rock sampled by the Perseverance Mars rover, the light-collecting power of the James Webb Space Telescope, the composition of asteroid (16) Psyche, and the type of solar eclipse we can expect in October.

Read on to learn more about the science and engineering behind each problem or click the link below to jump right into the challenge.

› Take the NASA Pi Day Challenge

› Educators, get the lesson here!

Tubular Tally

NASA’s Mars rover, Perseverance, was designed to collect rock samples that will eventually be brought to Earth by a future mission. Sending objects from Mars to Earth is very difficult and something we've never done before. To keep the rock cores pristine on the journey to Earth, the rover hermetically seals them inside a specially designed sample tube. Once the samples are brought to Earth, scientists will be able to study them more closely with equipment that is too large to make the trip to Mars. In Tubular Tally, students use pi to determine the volume of a rock sample collected in a single tube.

Rad Reflection

When NASA launched the Hubble Space Telescope in 1990, scientists hoped that the telescope, with its large mirror and sensitivity to ultraviolet, visible, and near-infrared light, would unlock secrets of the universe from an orbit high above the atmosphere. Indeed, their hope became reality. Hubble’s discoveries, which are made possible in part by its mirror, rewrote astronomy textbooks. In 2022, the next great observatory, the James Webb Space Telescope, began exploring the infrared universe with an even larger mirror from a location beyond the orbit of the Moon. In Rad Reflection, students use pi to gain a new understanding of our ability to peer deep into the cosmos by comparing the area of Hubble’s primary mirror with the one on Webb.

Metal Math

Orbiting the Sun between Mars and Jupiter, the asteroid (16) Psyche is of particular interest to scientists because its surface may be metallic. Earth and other terrestrial planets have metal cores, but they are buried deep inside the planets, so they are difficult to study. By sending a spacecraft to study Psyche up close, scientists hope to learn more about terrestrial planet cores and our solar system’s history. That's where NASA's Psyche comes in. The mission will use specialized tools to study Psyche's composition from orbit. Determining how much metal exists on the asteroid is one of the key objectives of the mission. In Metal Math, students will do their own investigation of the asteroid's makeup, using pi to calculate the approximate density of Psyche and compare that to the density of known terrestrial materials.

Eclipsing Enigma

On Oct. 14, 2023, a solar eclipse will be visible across North and South America, as the Moon passes between Earth and the Sun, blocking the Sun's light from our perspective. Because Earth’s orbit around the Sun and the Moon’s orbit around Earth are not perfect circles, the distances between them change throughout their orbits. Depending on those distances, the Sun's disk area might be fully or only partially blocked during a solar eclipse. In Eclipsing Enigma, students get a sneak peek at what to expect in October by using pi to determine how much of the Sun’s disk will be eclipsed by the Moon and whether to expect a total or annular eclipse.

Teach It

Celebrate Pi Day by getting students thinking like NASA scientists and engineers to solve real-world problems in the NASA Pi Day Challenge. In addition to solving this year’s challenge, you can also dig into the more than 30 puzzlers from previous challenges available in our Pi Day collection. Completing the problem set and reading about other ways NASA uses pi is a great way for students to see the importance of the M in STEM.

Pi Day Resources

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  Pi in the Sky Lessons

  Here's everything you need to bring the NASA Pi Day Challenge into the classroom.

  Grades 4-12

  Time Varies

• 
  NASA Pi Day Challenge

  The entire NASA Pi Day Challenge collection can be found in one, handy slideshow for students.

  Grades 4-12

  Time Varies

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  How Many Decimals of Pi Do We Really Need?

  While you may have memorized more than 70,000 digits of pi, world record holders, a JPL engineer explains why you really only need a tiny fraction of that for most calculations.

• 
  18 Ways NASA Uses Pi

  Whether it's sending spacecraft to other planets, driving rovers on Mars, finding out what planets are made of or how deep alien oceans are, pi takes us far at NASA. Find out how pi helps us explore space.

• 
  10 Ways to Celebrate Pi Day With NASA on March 14

  Find out what makes pi so special, how it’s used to explore space, and how you can join the celebration with resources from NASA.

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  Infographic: Planet Pi

  This poster shows some of the ways NASA scientists and engineers use the mathematical constant pi (3.14) and includes common pi formulas.

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  Downloads

  Can't get enough pi? Download this year's NASA Pi Day Challenge graphics, including mobile phone and desktop backgrounds:

  • Pi in the Sky 10 Poster (PDF, 11.3 MB)
  • Perseverance Mars Rover Background: Phone | Desktop
  • James Webb Space Telescope Background: Phone | Desktop
  • Psyche Mission Background: Phone | Desktop
  • 2023 Eclipse Background: Phone | Desktop
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  National Council of Teachers of Mathematics: Notice and Wonder

  Creative brainstorming through noticing and wondering encourages student participation, engagement, and students' understanding of the NASA Pi Day Challenge.

  Subject Mathematics

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  Pi Day: What's Going 'Round

  Tell us what you're up to this Pi Day and share your stories and photos on our showcase page.

Plus, join the conversation using the hashtag #NASAPiDayChallenge on Facebook, Twitter, and Instagram.

Related Lessons for Educators

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  Robotic Arm Challenge

  In this challenge, students will create a model robotic arm to move items from one location to another. They will engage in the engineering design process to design, build and operate the arm.

  Grades K-8

  Time 30 min to 1 hour

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  NASA's Mission to Mars Student Challenge

  Take part in the exploration of Mars and bring students along for the ride with NASA's Perseverance rover.

  Grades K-12

  Time Varies

• 
  Moon Phases

  Students learn about the phases of the moon by acting them out.

  Grades 1-6

  Time 30 min to 1 hour

• 
  Modeling the Earth-Moon System

  Students learn about scale models and distance by creating a classroom-size Earth-Moon system.

  Grades 6-8

  Time 30 min to 1 hour

• 
  Math of the Expanding Universe

  Students will learn about the expanding universe and the redshift of lightwaves, then perform their own calculations with a distant supernova.

  Grades 9-12

  Time 30 min to 1 hour

• 
  The Expanded Universe: Playing with Time Activity Guide

  In this activity, participants use balloons to model the expansion of the universe and observe how expansion affects wavelengths of light and distance between galaxies

• 
  James Webb Space Telescope STEM Toolkit

  Find a collection of resources, activities, videos, and more for your students to learn about NASA’s newest space observatory.

• 
  Modeling an Asteroid

  Lead a discussion about asteroids and their physical properties, then have students mold their own asteroids out of clay.

  Grades 3-5

  Time 30 min to 1 hour

• 
  Math Rocks: A Lesson in Asteroid Dynamics

  Students use math to investigate a real-life asteroid impact.

  Grades 8-12

  Time 30 min to 1 hour

Related Activities for Students

• 
  How to Make a Pinhole Camera

  Learn how to make your very own pinhole camera to safely see a solar eclipse in action!

  Type Project

  Subject Engineering

• 
  Collection: Exploring Mars

  Make a cardboard rover, design a Mars exploration video game and explore more STEM projects, slideshows and videos for students.

  Type Project

  Subject Science

• 
  What's That Space Rock?

  Find out how to tell the difference between asteroids, comets, meteors, meteorites and other bodies in our solar system.

  Type Slideshow

  Subject Science

• 
  10 Things We Can Learn from Webb's First Images

  Take a closer look at how images from NASA's most powerful space telescope yet are helping to answer some of astronomers' most burning questions.

  Type Slideshow

  Subject Science

Recursos en español

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  18 Maneras en Que la NASA Usa Pi

  Pi nos lleva lejos en la NASA. Estas son solo algunas de las formas en que pi nos ayuda a explorar el espacio.

Facts and Figures

• Asteroids Overview
• Eclipse Facts & Safety
• Mars Sample Handling
• Webb Telescope Key Facts

Websites

• Webb Space Telescope
• Mars Exploration
• Perseverance Mars Rover
• Mars Sample Return
• Psyche Mission
• MIRI Instrument
• 2023 Eclipse

Articles

• NASA’s Perseverance Rover Completes Mars Sample Depot

Videos

• Bringing Mars Rock Samples Back to Earth

Interactives

• Eyes on Asteroids

TAGS: Pi Day, Pi, Math, NASA Pi Day Challenge, sun, moon, earth, eclipse, asteroid, psyche, sample return, mars, perseverance, jwst, webb, hubble, telescope, miri

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  ABOUT THE AUTHOR

  Lyle Tavernier, Educational Technology Specialist, NASA-JPL Education Office

  Lyle Tavernier is an educational technology specialist at NASA's Jet Propulsion Laboratory. When he’s not busy working in the areas of distance learning and instructional technology, you might find him running with his dog, cooking or planning his next trip.

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After more than four years listening to the “heartbeat” of Mars, NASA is saying goodbye to the InSight lander as the mission on the Red Planet comes to an end. On Dec. 21, 2022 scientists wrapped up the first-of-its-kind mission to study the interior of Mars as dust in the Martian atmosphere and on the spacecraft’s solar panels prevented the lander from generating enough power to continue.

Read on to learn how the mission worked, what it discovered, and how to bring the science and engineering of the mission into the classroom.

How It Worked

The InSight lander was designed to reveal the processes that led to the formation of Mars – as well as Earth, the Moon, and all rocky worlds. This meant meeting two main science goals.

First, scientists wanted to understand how Mars formed and evolved. To do that, they needed to investigate the size and make-up of Mars’ core, the thickness and structure of its crust, the structure of the mantle layer, the warmth of the planet's interior, and the amount of heat flowing through the planet.

Second, to study tectonic activity on Mars, scientists needed to determine the power, frequency, and location of “marsquakes” as well as measure how often meteoroids impacted the Red Planet, creating seismic waves.

Engineers equipped InSight with three main science tools that would allow researchers to answer these questions about Mars.

SEIS, a seismometer like the ones used on Earth to record earthquakes, measured the seismic waves on Mars. These waves, which travel through the Red Planet, can tell scientists a lot about the areas they pass through. They even carry clues about whether it was a marsquake or meteorite impact that created the waves.

InSight's Heat Flow and Physical Properties Package, or HP3, was an instrument designed to burrow 16 feet (five meters) into Mars to measure the temperature at different depths and monitor how heat flowed out toward the surface. However, the self-hammering probe, informally called the "mole," struggled to dig itself in due to the unexpected consistency of the top few inches of Mars regolith at the landing site. Using full-size models of the lander and probe, engineers recreated InSight’s environment here on Earth to see if they could find a solution to the issue. They tested solutions that would allow the probe to penetrate the surface, including pressing the scoop attached to InSight’s robotic arm against the probe. While the effort serves as a great real-world example of how engineers work through problems with distant spacecraft, ultimately, none of the solutions allowed the probe to dig past the surface when attempted on Mars.

In 2019, InSight mission scientist/engineer Troy Hudson shared the game plan for getting the mission's heat probe digging again on Mars. Ultimately, the team wasn't able to to get the "mole" working, but the effort is a great real-world example of how engineers work through problems with distant spacecraft. | Watch on YouTube

InSight’s third experiment, called RISE, used the spacecraft’s radio antennas to precisely measure the lander's position on the surface of Mars. The interior structure of Mars affects the planet’s motion, causing it to wobble. Measuring InSight’s position as the planet wobbled helped scientists gain a better understanding of the core and other layered structures that exist within the interior of Mars.

What We Discovered

InSight’s instruments enabled the mission science team to gain an understanding of not only the depth of Mars’ crust, mantle, and core, but also the composition of those features. They also learned just how active Mars really is.

The Structure of Mars

Working our way from the surface to the center of the planet, scientists found Mars’ crust was thinner than expected. Seismic waves detected by SEIS indicate that the crust is made up of three sub-layers, similar to Earth’s crust. The top-most layer of the crust is about six miles (10 kilometers) deep, while the denser layers of the crust, which contain more felsic, or iron-rich, material extend downward to about 25 miles (40 kilometers) below the surface. As seismic waves from a marsquake or a meteorite impact spread across the surface and through the interior of the planet, they can reflect off of underground layers, giving scientists views into the unseen materials below. Measuring how the waves change as a result of these reflections is how scientists unveiled the underground structure of Mars.

Like Earth, Mars has a lithosphere, a rigid layer made up of the crust and upper mantle. The Martian lithosphere extends about 310 miles (500 kilometers) below the surface before it transitions into the remaining mantle layer, which is relatively cool compared with Earth’s mantle. Mars’ mantle extends to 969 miles (1,560 kilometers) below the surface where it meets the planet’s core.

Scientists measured the core of Mars and found it to be larger than expected, with a radius of 1,137 miles (1,830 kilometers). With this information, scientists were able to estimate the density of Mars' core, which turned out to be less dense than anticipated, meaning it contains lighter elements mixed in with iron. Scientists also confirmed that the planet contains a liquid core. While we know that Earth has a liquid outer core and solid inner core, scientists will need to further study the data returned from InSight to know if there is also a solid inner core on Mars.

As scientists continue to study the data returned from InSight, we could learn even more about how Mars formed, how its magnetic field developed, and what materials make up the core, which could ultimately help us better understand how Earth and other planets formed.

Marsquakes

InSight discovered that Mars is a very active planet. A total of 1,319 marsquakes were detected after the SEIS instrument was placed on the surface. The largest, which was estimated to be a magnitude 5, was detected in May of 2022.

Unlike Earth, where the crust is broken into large pieces called plates that continually shift around causing earthquakes, Mars’ crust is made up of one solid plate, somewhat like a shell. However, as the planet cools, the crust shrinks, creating breaks called faults. This breaking action is what causes marsquakes, and the seismic waves generated by the quakes are what help scientists figure out when and where the quakes occurred and how powerful they were.

Nearly all of the strongest marsquakes detected by InSight came from a region known as Cerberus Fossae, a volcanic region that may have had lava flows within the past few million years. Volcanic activity, even without lava flowing on the surface, can be another way marsquakes occur. Images from orbiting spacecraft show boulders that have fallen from cliffs in this region, perhaps shaken loose by large marsquakes.

Conversely, InSight didn't detect any quakes in the volcanic region known as Tharsis, the home of three of Mars’ largest volcanos that sit approximately one-third of the way around the planet from InSight. This doesn’t necessarily mean the area is not seismically active. Scientists think there may be quakes occurring, but the size of Mars’ liquid core creates what’s known as a shadow zone – an area into which seismic waves don’t pass – at InSight's location.

Meteorite Impacts

On Sept. 5, 2021, InSight detected the impacts of a meteoroid that entered the Martian atmosphere. The meteoroid exploded into at least three pieces that reached the surface and left behind craters. NASA’s Mars Reconnaissance Orbiter passed over the impact sites to capture images of the three new craters and confirm their locations.

“After three years of waiting for an impact, those craters looked beautiful,” said Ingrid Daubar of Brown University, a Mars impacts specialist.

Mars’ thin atmosphere, which is less than 1% as dense as Earth’s, means meteoroids have a better chance of not disintegrating in the heat and pressure that builds up as they pass through the atmosphere to the planet’s surface. Despite this fact and Mars' proximity to the asteroid belt, the planet proved to be a challenging location to detect meteorite impacts because of "noise" in the data created by winds blowing on SEIS and seasonal changes in the atmosphere.

With the confirmation of the September 2021 impacts, scientists were able to identify a telltale seismic signature to these meteorite impacts. With this information in hand, they looked back through InSight's data and found three more impacts – one in 2020 and two in 2021. Scientists anticipate finding even more impacts in the existing data that might have been hidden by the noise in the data.

Meteorite impacts are an invaluable piece of understanding the planet’s surface. On a planet like Earth, wind, rain, snow and ice wear down surface features in a process known as weathering. Plate tectonics and active volcanism refresh Earth’s surface regularly. Mars’ surface is older and doesn't go through those same processes, so a record of past geologic events like meteorite impacts is more apparent on the planet's surface. By counting impact craters visible on Mars today, scientists can update their models and better estimate the number of impacts that occurred in the early solar system. This gives them an improved approximation of the age of the planet’s surface.

Learn how InSight detected the first seismic waves from a meteoroid on Mars and how the lander captured the sound of the space rock striking the surface. | Watch on YouTube

Why It's Important

Before InSight touched down, all Mars missions – landers, rovers, orbiters and flyby spacecraft – studied the surface and atmosphere of the planet. InSight was the first mission to study the deep interior of Mars.

Even with the InSight mission drawing to a close, the science and engineering of the mission will continue to inform our understanding of the Red Planet and our solar system for years as researchers further examine the data returned to Earth. Keep up to date with the latest findings from InSight scientists and engineers on the mission website.

Teach It

Explore these lessons in geology, physics, math, coding and engineering to connect student learning to the InSight mission and the real-world STEM that happens at NASA.

Educator Resources

• 
  Collection

  InSight Lessons for Educators

  Explore a collection of standards-aligned lessons to bring the science and engineering of the InSight mission into the classroom.

• 
  Collection

  NASA's Mission to Mars Student Challenge

  Get K-12 students exploring Mars with NASA scientists, engineers, and the Perseverance rover as they learn all about STEM and design their very own mission to the Red Planet!

• 
  Teachable Moments

  NASA InSight Lander to Get First Look at ‘Heart’ of Mars

  Learn what it takes to travel to Mars and get students engaged with lessons in calculating trajectories, plus building and launching rockets.

• 
  Teachable Moments

  Mars Landing to Deliver Science Firsts

  Find out how NASA’s InSight lander will collect all-new science at Mars, then get students doing similar investigations in the classroom.

Student Activities

• 
  Collection

  Exploring Mars Activities

  Make a cardboard rover, design a Mars exploration video game, learn about Mars in a minute and explore more STEM activities for students.

Explore More

• Website: Mars InSight Mission
• Podcast: On a Mission - Season 1
• Articles: JPL News - InSight Mission
• Videos: InSight Mission Videos
• Images: InSight Mission Images
• Video: Interns Explore the Future at NASA-JPL
• Videos: Inside InSight - YouTube Playlist
• Videos: InSight Mission to Mars - YouTube Playlist
• Interactive: Experience InSight
• Website: NASA Mars Exploration
• Articles: People - Meet the Martians
• Resources for Kids: Space Place - All About Mars

TAGS: K-12 Education, Classrooms, Teaching, Teachers, Resources, Teachable Moments, Mars, InSight, Missions, Spacecraft, Marsquakes

• 

  ABOUT THE AUTHOR

  Lyle Tavernier, Educational Technology Specialist, NASA-JPL Education Office

  Lyle Tavernier is an educational technology specialist at NASA's Jet Propulsion Laboratory. When he’s not busy working in the areas of distance learning and instructional technology, you might find him running with his dog, cooking or planning his next trip.

Update: Dec. 15, 2022 – NASA, the French space agency, and SpaceX are now targeting 3:46 a.m. PST (6:46 a.m. EST) on Friday, Dec.16, for the launch of the Surface Water and Ocean Topography (SWOT) satellite. Visit NASA's SWOT launch blog for the latest updates.

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NASA is launching an Earth-orbiting mission that will map the planet’s surface water resources better than ever before. Scheduled to launch on Dec. 16 from Vandenberg Space Force Base in California, the Surface Water and Ocean Topography, or SWOT mission is the latest international collaboration designed to monitor and report on our home planet. By providing us with a highly detailed 3D view of rivers, lakes, and oceans, SWOT promises to improve our understanding of Earth’s water cycle and the role oceans play in climate change, as well as help us better respond to drought and flooding.

Read on to find out why we're hoping to learn more about Earth's surface water, get to know the science behind SWOT's unique design, and follow along with STEM teaching and learning resources.

Why It's Important

Observing Earth from space provides scientists with a global view that is important for understanding the whole climate system. In the case of SWOT, we will be able to monitor Earth’s surface water with unprecedented detail and accuracy. SWOT will provide scientists with measurements of water volume change and movement that will inform our understanding of fresh water availability, flood hazards, and the mechanisms of climate change.

Scientists and engineers provide an overview of the SWOT mission. Credit: NASA/JPL-Caltech | Watch on YouTube

Water Flow

Scientists use a variety of methods to track Earth’s water. These include stream and lake gauges and even measurements from space such as sea surface altimetry and gravitational measurements of aquifer volumes. Monitoring of river flow and lake volume is important because it can tell us how much freshwater is readily available and at what locations. River flow monitoring can also help us make inferences about the downstream environmental impact. But monitoring Earth’s surface water in great detail with enough frequency to track water movement has proven challenging. Until now, most monitoring of river flow and lake levels has relied on water-flow and water-level gauges placed across Earth, which requires that they be accessible and maintained. Not all streams and lakes have gauges and previous space-based altimetry and gravitational measurements, though useful for large bodies of water, have not been able to adequately track the constant movement of water through smaller rivers or lakes.

Here's why understanding Earth’s "water budget" is an important part of understanding our planet and planning for future water needs.

SWOT will be able to capture these measurements across the globe in 3D every 21 days. The mission will monitor how much water is flowing through hundreds of thousands of rivers wider than 330 feet (100 meters) and keep a close watch on the levels of more than a million lakes larger than 15 acres (6 hectares). Data from the mission will be used to create detailed maps of rivers, lakes, and reservoirs that will enable accurate monitoring to provide a view of freshwater resources that is not reliant on physical access. Meanwhile, SWOT’s volumetric measurements of rivers, lakes, and reservoirs will help hydrologists better track drought and flooding impacts in near-real-time.

Coastal Sea Level Rise

SWOT will measure our oceans with unprecedented accuracy, revealing details of ocean features as small as 9 miles (15 kilometers) across. SWOT will also monitor sea levels and tides. Though we have excellent global sea level data, we do not have detailed sea level measurements near coastlines. Coastal sea levels vary across the globe as a result of ocean currents, weather patterns, land changes, and other factors. Sea levels are rising faster than ever, and higher sea levels also mean that hurricane storm surges will reach farther inland than ever before, causing substantially more damage than the same category of hurricanes in the past. SWOT will be able to monitor coastal sea level variations and fill gaps in the observations we currently have from other sources.

What is sea level rise and what does it mean for our planet? | › View Transcript

Ocean Heat Sinks

Further contributing to our understanding of the role Earth’s oceans play in climate change, SWOT will explore how the ocean absorbs atmospheric heat and carbon, moderating global temperatures and climate change. Scientists understand ocean circulation on a large scale and know that ocean currents are driven by temperature and salinity differences. However, scientists do not currently have a good understanding of fine-scale ocean currents, where most of the ocean's motion-related energy is stored and lost. Circulation at these fine scales is thought to be responsible for transporting half of the heat and carbon from the upper ocean to deeper layers. Such downward ocean currents have helped to mitigate the decades-long rise in global air temperatures by absorbing and storing heat and carbon away from the atmosphere. Knowing more about this process is critical for understanding the mechanisms of global climate change.

JPL scientist Josh Willis uses a water balloon to show how Earth's oceans are absorbing most of the heat being trapped on our warming world. | › Related lesson

These fine-scale ocean currents also transport nutrients to marine life and circulate pollutants such as crude oil and debris. Understanding nutrient transport helps oceanographers assess ocean health and the productivity of fisheries. And tracking pollutants aids in natural hazard assessment, prediction, and response.

How It Works

A joint effort between NASA and the French space agency – with contributions from the Canadian and UK space agencies – SWOT will continue NASA’s decades-long record of monitoring sea surface height across the globe. But this mission will add a level of detail never before achieved.

SWOT will measure more than 90% of Earth’s surface water, scanning the planet between 78°N latitude and 78°S latitude within 1 centimeter of accuracy and retracing the same path every 21 days. Achieving this level of accuracy from a spacecraft height of 554 miles (891 kilometers) requires that the boom using radar to measure water elevation remain stable within 2 microns – or about 3% of the thickness of a human hair.

This visualization shows ocean surface currents around the world during the period from June 2005 through December 2007. With its new, high resolution wide-swath measurements, SWOT will be able to observe eddies and current features at greater resolution than previously possible. Credit: NASA Scientific Visualization Studio | Watch on YouTube

Prior to SWOT, spacecraft have used conventional nadir, or straight-down, altimetry to measure sea surface height. Conventional nadir altimetry sends a series of radar or laser pulses down to the surface and measures the time it takes for each signal to return to the spacecraft, thus revealing distances to surface features. To acquire more detailed information on surface water, SWOT will use an innovative instrument called the Ka-band Radar Interferometer, or KaRIn, to measure water height with exceptional accuracy. Ka-band is a portion of the microwave part of the electromagnetic spectrum. SWOT uses microwaves because they can penetrate clouds to return data about water surfaces.

The KaRIn instrument uses the principles of synthetic aperture radar combined with interferometry to measure sea surface height. A radar signal is emitted from the end of the 10-meter-wide boom on the spacecraft. The reflected signal is then received by antennas on both ends of the boom, capturing data from two 30-mile (50-kilometer) wide swaths on either side of the spacecraft. The received signals will be slightly out of sync, or phase, from one another because they will travel different distances to return to the receivers on either end of the boom. Knowing the phase difference, the distance between the antennas, and the radar wavelength allows us to calculate the distance to the surface.

The observations acquired by the two antennas can be combined into what is known as an interferogram. An interferogram is a pattern of wave interference that can reveal more detail beyond the 1-centimeter resolution captured by the radar. To explain how it works, we'll recall a couple of concepts from high school physics. When out-of-phase waves from the two antennas are combined, constructive and destructive interference patterns result in some wave crests being higher and some wave troughs being lower than those of the original waves. The patterns that result from the combination of the waves reveal more detail with resolution better than the 1-centimeter wavelength of the original Ka-band radar waves because the interference occurs over a portion of a wavelength. An interferogram can be coupled with elevation data to reveal a 3D representation of the water’s surface.

This highly accurate 3D view of Earth’s surface water is what makes SWOT so unique and will enable scientists to more closely monitor the dynamics of the water cycle. In addition to observing ocean currents and eddies that will inform our understanding of the ocean’s role in climate change, SWOT's use of interferometry will allow scientists to track volumetric changes in lakes and quantify river flooding, tasks that cannot yet be done on a wide scale in any other way.

Follow Along

SWOT is scheduled to launch no earlier than Dec. 16, 2022, on a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California. Tune in to watch the launch on NASA TV.

After launch, the spacecraft will spend 6-months in a calibration and validation phase, during which it will make a full orbit of Earth every day at an altitude of 553 miles (857 kilometers). Upon completion of this phase, SWOT will increase its altitude to 554 miles (891 kilometers) and assume a 21-day repeat orbit for the remainder of its mission.

Visit the mission website to follow along as data are returned and explore the latest news, images, and updates as SWOT provides a new view on one of our planet's most important resources.

Teach It

The SWOT mission is the perfect opportunity to engage students in studying Earth’s water budget and water cycle. Explore these lessons and resources to get students excited about the STEM involved in studying Earth’s water and climate change from space.

Educator Resources

• 
  Collection

  SWOT Mission Lessons for Educators

  Explore the science and engineering behind the SWOT mission with this collection of standards-aligned lessons all about water.

• 
  Collection

  Climate Change Lessons for Educators

  Explore a collection of standards-aligned STEM lessons for students that get them investigating climate change along with NASA.

• 
  Collection

  Teachable Moments in Climate Change

  Explore this collection of Teachable Moments articles to get a primer on the latest NASA Earth science missions, plus find related education resources you can deploy right away!

• 
  Expert Talk

  Teaching Space With NASA – Monitoring Earth from Space

  In this educational talk, NASA experts discuss how we build spacecraft to study climate, then answer audience questions.

Student Activities

• 
  Collection

  SWOT Mission Activities for Students

  Explore projects, videos, slideshows, and games for students all about the water cycle and sea level rise.

• 
  Collection

  Climate Change Activities for Students

  Learn about climate change and its impacts with these projects, videos, and slideshows for students.

• 
  Collection

  Earth Minute Video Series

  This series of animated white-board videos for students of all ages explains key concepts about Earth science, missions, and climate change.

Explore More

Activities for Kids

• Download: SWOT Launch Bingo
• Video: How Much Water is on Earth?
• Game: Go With the Flow – An Ocean Currents Game

Websites

• SWOT Mission Website
• NASA Climate Change
• NASA Earth Observatory
• NASA Climate Kids
• NASA Sea Level Change
• NASA Cambio Climático en Español

Facts & Figures

• NASA Climate Change: Evidence
• NASA Earth Science Missions

Videos

• Mission Makers - SWOT
• SWOT Mission - YouTube Playlist

Interactives

• Earth Now
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Image Gallery

• NASA climate images, videos, and graphics
• Images of Change

Articles

• Climate articles from NASA
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• Water Mission to Gauge Alaskan Rivers on Front Lines of Climate Change

Podcast

• On a Mission

TAGS: K-12 Education, Teachers, Educators, Earth Science, Earth, Climate Change, Climate, Satellites, Teachable Moments

• 

  ABOUT THE AUTHOR

  Ota Lutz, K-12 Education Group Manager, NASA-JPL Education Office

  Ota Lutz is the manager of the K-12 Education Group at NASA’s Jet Propulsion Laboratory. When she’s not writing new lessons or teaching, she’s probably cooking something delicious, volunteering in the community, or dreaming about where she will travel next.

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Some of the wildest, most exciting features of our universe – from black holes to neutron stars – remain mysteries to us. What we do know is that because of their extreme environments, some of these emit highly energetic X-ray light, which we can detect despite the vast distances between us and the source.

Now, a NASA space telescope mission is using new techniques to not only scout out these distant phenomena, but also provide new information about their origins. Read on to learn how scientists are getting exciting new perspectives on our universe and what the future of X-ray astronomy holds.

How They Did It

In 2021, NASA launched the Imaging X-Ray Polarimeter Explorer, or IXPE, through a collaboration with Ball Aerospace and the Italian Space Agency. The space telescope is designed to operate for two years, detecting X-rays emitted from highly energetic objects in space, such as black holes, different types of neutron stars (e.g., pulsars and magnetars) and active galactic nuclei. In its first year, the telescope is focusing on roughly a dozen previously studied X-ray sources, spending hours or even days observing each target to reveal new data made possible by spacecraft's scientific instruments.

IXPE isn't the first telescope to observe the universe in X-ray light. NASA's Chandra X-ray Observatory, launched in 1999, has famously spent more than 20 years photographing our universe at a wavelength of light exclusively found in high-energy environments, such as where cosmic materials are heated to millions of degrees as a result of intense magnetic fields or extreme gravity.

Using Chandra, scientists can assign colors to the different energy levels, or wavelengths, produced by these environments. This allows us to get a picture of the highly energetic light ejected by black holes and tiny neutron stars – small, but extremely dense stars with masses 10-25 times that of our Sun. These beautiful images, such as from Chandra’s first target, Cassiopeia A (Cas A for short), show the violent beauty of stars exploding.

While Chandra has earned its name as one of “The Great Observatories,” astronomers have long desired to peer further into highly energetic environments in space by capturing them in even more detail.

IXPE expands upon Chandra’s work with the introduction of a tool called a polarimeter, an instrument used to understand the shape and direction of the light that reaches the space telescope's detectors. The polarimeter on IXPE allows scientists to gain insight into the finer details of black holes, supernovas, and magnetars, like which direction they are spinning and their three-dimensional shape.

While scientists have just begun putting IXPE's capabilities to use, they're already starting to reveal new details about the inner workings of these objects – such as the magnetic field environment around Cas A, shown in a newly released image.

“For the first time, we will use every collected photon of light to tell us about the nature and shapes of objects in the sky that would be dots of light otherwise,” says Roger Romani, a Stanford professor and the co-investigator on IXPE.

How It Works

Generally, when light is produced, it is what we call unpolarized, meaning that it oscillates in every direction. For example, our Sun produces unpolarized light. But sometimes, light is produced in a highly organized fashion, oscillating only in one direction. In astronomy, this arises when magnetic fields force particles to incredibly high speeds, creating highly organized, or polarized, light.

This is what makes objects like the supernova Cas A such enticing targets for IXPE. Exploded stars like Cas A generate massive energetic waves when they go supernova, giving scientists a view of how particles shooting out at immense speeds interact with the magnetic fields from such an event. In the case of Cas A, IXPE was able to determine that the x-rays are not very polarized, meaning the explosion created very turbulent regions with multiple field directions.

While the idea of polarized or organized light may sound abstract, you may have noticed it the last time you were outside on a sunny day. If you’ve tried on a pair of polarized sunglasses, you may have noticed that the glare was greatly reduced. That’s because as light scatters, it bounces off of reflective surfaces in all directions. However, polarized lenses have tiny filters that only allow light coming from a narrow band of directions to pass through.

The polarimeter on IXPE works in a similar way. Astronomers can determine the strength of an object's magnetic field by using the polarimeter to measure how much of the light detected by the telescope is polarized. Typically, the more polarized the light the stronger the magnetic field at the source.

Astronomers can even go a step further to measure the direction this light is oscillating by measuring the angle of the light that reaches the telescope. Because the polarized light leaves the source in a predictable fashion – namely perpendicular from its magnetic field – knowing the angle of the oscillating light provides information about the axis of rotation and potentially even the surface structure of objects such as neutron stars and nebulae.

Imagine, for example, that you were holding one end of a piece of rope secured to an object at the other end. If you swung the rope side to side to make horizontal waves, those waves would be able to make it through a narrow target like a window. If you started to shut the window from the top, narrowing the opening, the waves could conceivably still make it through the opening. However, if you made veritcal waves by waving the rope up and down, as the window closed, fewer and fewer waves would make it through the opening. Likewise, by measuring the light that makes it through the polarimeter to the detector on the other side, IXPE can determine the angle of the light received.

To collect this light, IXPE uses three identical mirrors at the end of a four meter (13 foot) boom. The light received by IXPE is carefully focused on the spacecraft’s polarimeter at the other end of the boom, allowing scientists to collect those crucial measurements.

During the IXPE launch broadcast, commentators discuss the components of the spacecraft and how it measures polarization. | Watch on YouTube

Why It's Important

Building on Chandra's observations from the past two decades, IXPE's novel approach to X-ray science is pulling the curtain back even farther on some of the most fascinating objects in the universe, providing first looks at how and where radiation is being produced in some of the most extreme environments in the universe. IXPE's measurements of Cas A are just the beginning, with even more mysterious targets ready to be explored.

Take it from Martin Weisskopf, the principal scientist on IXPE and project scientist for Chandra, who has spent his 50-year career working in X-ray astronomy, who says, “IXPE will open up the field in ways we’ve been stuck only theorizing about."

Teach It

Explore more on how NASA uses light to map our universe, and dig deeper into some of the celestial features it allows to study, such as blackholes and neutron stars.

Activities

• 
  Project

  Exploring Materials - Polarizers

  In this activity, learners experiment how polarizers affect light by using two polarizing sheets and overlapping layers of transparent tape.

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  Activity Guidebook

  Girls STEAM Ahead with NASA Program Cookbook

  A guidebook for facilitators planning their own Girls STEAM Ahead with NASA event using NASA’s Universe of Learning resources.

• 
  Slideshow

  Black Holes: By the Numbers

  What are black holes and how do they form? Explore more in this slideshow.

• 
  Video

  What Is a Black Hole?

  Find out how what a black hole is, how they can form and why they are so cool!

Educator Resources

• 
  Science Briefing: Exploring the High Energy Universe

  Explore the event materials from this science briefing to get a window into the most energetic processes and the most extreme objects in the universe.

  Subject Science

• 
  The Science of Color

  Quickly and easily model how colors reflect, absorb, and interact with each other in the classroom or online using your computer’s camera.

  Subject Science

  Grades 2-8

  Time < 30 mins

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  Using Light to Study Planets

  Students build a spectrometer using basic materials as a model for how NASA uses spectroscopy to determine the nature of elements found on Earth and other planets.

  Subject Science

  Grades 6-11

  Time 2+ hrs

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  Dropping In With Gravitational Waves

  Students develop a model to represent the collision of two black holes, the gravitational waves that result and the waves' propagation through spacetime.

  Subject Science

  Grades 6-8

  Time 30-60 mins

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  Teachable Moments

  Telescopes Get Extraordinary View of Milky Way's Black Hole

  Find out how scientists captured the first image of Sagittarius A*, why it's important, and how to turn it into a learning opportunity for students.

• 
  Teachable Moments

  How Scientists Captured the First Image of a Black Hole

  Find out how scientists created a virtual telescope as large as Earth itself to capture the first image of a black hole's silhouette.

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  Teachable Moments

  Gravitational Waves Detected for the First Time

  Find out how researchers proved part of Albert Einstein’s Theory of General Relativity, then create a model of the Nobel Prize-winning experiment in the classroom.

Explore More

• Article: NASA’S IXPE Helps Unlock the Secrets of Famous Exploded Star
• Educator Guide: Black Hole Math
• Opportunity: NASA/IPAC TeacherArchive Research Program
• Student Resources: Chandra
• Article: Hubble - Black Holes
• Interactive: Sagittarius A*
• Video: Hubble - Black Holes
• Website: NASA Science - Black Holes
• Download: A Galaxy Full of Black Holes Presentation
• Expert Talk: Imaging a Black Hole Lecture
• Facts & Figures: NASA - Black Holes
• Article: Black Hole Image Makes History
• Infographic: Anatomy of a Black Hole

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NASA's Universe of Learning materials are based upon work supported by NASA under award number NNX16AC65A to the Space Telescope Science Institute, working in partnership with Caltech/IPAC, Center for Astrophysics | Harvard & Smithsonian, and the Jet Propulsion Laboratory.

TAGS: Universe, Stars and Galaxies, Space Telescope, IXPE, Astronomy, Science, Electromagnetic Spectrum, Universe of Learning

• 

  ABOUT THE AUTHOR

  Brandon Rodriguez, Educator Professional Development Specialist, NASA-JPL Education Office

  Brandon Rodriguez is the educator professional development specialist at NASA’s Jet Propulsion Laboratory. Outside of promoting STEM education, he enjoys reading philosophy, travel and speaking to your dog like it's a person.

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Update: Oct. 20, 2022 – The DART spacecraft successfully impacted the asteroid Dimorphos on September 26, reducing the period of the asteroid's orbit by 32 minutes. Scientists considered a change of 73 seconds to be the minimum amount for success. This article has been updated to reflect the latest data and images from the impact.

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In a successful attempt to alter the orbit of an asteroid for the first time in history, NASA crashed a spacecraft into the asteroid Dimorphos on Sept. 26, 2022. The mission, known as the Double Asteroid Redirection Test, or DART, took place at an asteroid that posed no threat to our planet. Rather, it was an ideal target for NASA to test an important element of its planetary defense plan.

Read further to learn about DART, how it worked, and how the science and engineering behind the mission can be used to teach a variety of STEM topics.

Why It's Important

The vast majority of asteroids and comets are not dangerous, and never will be. Asteroids and comets are considered potentially hazardous objects, or PHOs, if they are 100-165 feet (30-50 meters) in diameter or larger and their orbit around the Sun comes within five million miles (eight million kilometers) of Earth’s orbit. NASA's planetary defense strategy involves detecting and tracking these objects using telescopes on the ground and in space. In fact, NASA’s Center for Near Earth Object Studies, or CNEOS, monitors all known near-Earth objects to assess any impact risk they may pose. Any relatively close approach is reported on the Asteroid Watch dashboard.

While there are no known objects currently posing a threat to Earth, scientists continue scanning the skies for unknown asteroids. NASA is actively researching and planning for ways to prevent or reduce the effects of a potential impact, should one be discovered. The DART mission was the first test of such a plan – in this case, whether it was possible to divert an asteroid from its predicted course by slamming into it with a spacecraft.

Eyes on Asteroids is a real-time visualization of every known asteroid or comet that is classified as a near-Earth object, or NEO. Asteroids are represented as blue dots and comets as shown as white dots. Use your mouse to explore the interactive further and learn more about the objects and how we track them. Credit: NASA/JPL-Caltech | Explore the full interactive

With the knowledge gained from the demonstration, similar techniques could be used in the future to deflect an asteroid or comet away from Earth if it were deemed hazardous to the planet.

How It Worked

With a diameter of about 525 feet (160 meters) – the length of 1.5 football fields – Dimorphos is the smaller of two asteroids in a double-asteroid system. Before DART's impact, Dimorphos orbited the larger asteroid called Didymos (Greek for "twin"), every 11 hours and 55 minutes.

Neither asteroid poses a threat to our planet, which is one reason why this asteroid system was the ideal place to test asteroid redirection techniques. At the time of DART's impact, the asteroid pair was 6.8 million miles (11 million kilometers) away from Earth as they traveled on their orbit around the Sun.

The DART spacecraft was designed to collide head-on with Dimorphos to alter its orbit, shortening the time it takes the small asteroid to travel around Didymos. Compared with Dimorphos, which has a mass of about 11 billion pounds (five billion kilograms), the DART spacecraft was light. It weighed just 1,210 pounds (550 kilograms) at the time of impact. So how did such a light spacecraft affect the orbit of a relatively massive asteroid?

You can use your mouse to explore this interactive view of DART's impact with Dimorphos from NASA's Eyes on the Solar System. Credit: NASA/JPL-Caltech | Explore the full interactive

DART was designed as a kinetic impactor, meaning it transferred its momentum and kinetic energy to Dimorphos upon impact, altering the asteroid's orbit in return. Scientists were able to make predictions about some of these effects thanks to principles described in Newton's laws of motion.

Newton’s first law told us that the asteroid’s orbit would remain unchanged until something acted upon it. Using the formula for linear momentum (p = m * v), we could calculate that the spacecraft, which at the time of impact would be traveling at 3.8 miles (6.1 kilometers) per second, would have about 0.5% of the asteroid’s momentum. The momentum of the spacecraft may seem small in comparison, but calculations suggested it would be enough to make a detectable change in the speed of Dimorphos' orbit. However, mission planners felt that changing Dimorphos’ orbit by at least 73 seconds would be enough to consider the test a success.

But there was more to consider in testing whether the technique could be used in the future for planetary defense. For example, the formula for kinetic energy (KE = 0.5 * m * v2) tells us that a fast moving spacecraft possesses a lot of energy.

When DART hit the surface of the asteroid, its kinetic energy was 10 billion joules! A crater was formed and material known as ejecta was blasted out as a result of the impact. Scientists are still studying the data returned from the mission to determine the amount of material ejected out of the crater, but estimates prior to impact put the number at 10-100 times the mass of the spacecraft itself. The force needed to push this material out was then matched by an equal reaction force pushing on the asteroid in the opposite direction, as described by Newton’s third law.

This animation shows conceptually how DART's impact is predicted to change Dimorphos' orbit from a larger orbit to a slightly smaller one that's several minutes shorter than the original. Credit: NASA/Johns Hopkins APL/Jon Emmerich | Watch on YouTube

How much material was ejected and its recoil momentum is still unknown. A lot depends on the surface composition of the asteroid, which scientists are still investigating. Laboratory tests on Earth suggested that if the surface material was poorly conglomerated, or loosely formed, more material would be blasted out. A surface that was well conglomerated, or densely compacted, would eject less material.

After the DART impact, scientists used a technique called the transit method to see how much the impact changed Dimorphos' orbit. As observed from Earth, the Didymos pair is what’s known as an eclipsing binary, meaning Dimorphos passes in front of and behind Didymos from our view, creating what appears from Earth to be a subtle dip in the combined brightness of the pair. Scientists used ground-based telescopes to measure this change in brightness and calculate how quickly Dimorphos orbits Didymos. By comparing measurements from before and after impact, scientists determined that the orbit of Dimorphos had slowed by 32 minutes to 11 hours and 23 minutes.

One of the biggest challenges of the DART mission was navigating a small spacecraft to a head-on collision with a small asteroid millions of miles away. To solve that problem, the spacecraft was equipped with a single instrument, the DRACO camera, which worked together with an autonomous navigation system called SMART Nav to guide the spacecraft without direct control from engineers on Earth. About four hours before impact, images captured by the camera were sent to the spacecraft's navigation system, allowing it to identify which of the two asteroids was Dimorphos and independently navigate to the target.

DART was not just an experimental asteroid impactor. The mission also used cutting-edge technology never before flown on a planetary spacecraft and tested new technologies designed to improve how we power and communicate with spacecraft.

Learn more about the engineering behind the DART mission, including the innovative Roll Out Solar Array and NEXT-C ion propulsion system, in this video featuring experts from the mission. Credit: APL | Watch on YouTube

One such technology that was first tested on the International Space Station and was later used on the solar-powered DART spacecraft, is the Roll Out Solar Array, or ROSA, power system. As its name suggests, the power system consisted of flexible solar panel material that was rolled up for launch and unrolled in space.

Some of the power generated by the solar array was used for another innovative technology, the spacecraft's NEXT-C ion propulsion system. Rather than using traditional chemical propulsion, DART was propelled by charged particles of xenon pushed from its engine. Ion propulsion has been used on other missions to asteroids and comets including Dawn and Deep Space 1, but DART's ion thrusters had higher performance and efficiency.

Follow Along

In the days following the event, NASA received images of the impact from a cubesat, LICIACube, that was deployed by DART before impact. The cubesat, which was provided by the Italian Space Agency, captured images of the impact and the ejecta cloud.

Meanwhile, the James Webb Space Telescope, the Hubble Space Telescope, and the Lucy spacecraft observed Didymos to monitor how soon reflected sunlight from the ejecta plume could be seen. Going forward, DART team members will continue observing the asteroid system to measure the change in Dimorphos’ orbit and determine what happened on its surface. And in 2024, the European Space Agency plans to launch the Hera spacecraft to conduct an in-depth post-impact study of the Didymos system.

Continue following along with all the science from DART, including the latest images and updates on the mission website. Plus, explore even more resources on this handy page.

Teach It

The mission is a great opportunity to engage students in the real world applications of STEM topics. Start exploring these lessons and resources to get students engaging in STEM along with the mission.

Educator Guides

• 
  Collection

  DART Lessons for Educators

  Use these standards-aligned lessons for grades K-12 to get students exploring the engineering and science behind the DART mission.

Expert Talks

• 
  Teaching Space With NASA

  Tracking Asteroids

  In this educational talk, NASA experts will discuss how we track and study comets and asteroids. Plus, we'll answer your questions!

Student Activities

• 
  Collection

  DART Activities for Students

  Explore STEM projects, slideshows and videos for students related to the DART mission.

Articles

• 
  Teachable Moments

  How NASA Studies and Tracks Asteroids Near and Far

  Here’s how NASA uses math and science to track the movements of asteroids and find out what they’re made of – and students can, too.

• 
  Meet JPL Interns

  From Island Life to Spotting Asteroids for NASA

  Meet a JPL intern whose journey took her from the remote island of Saipan to a team helping track asteroids at NASA.

Resources for Kids

Check out these related resources for kids from NASA Space Place:

• Article for Kids: Asteroid or Meteor: What's the Difference?
• Article for Kids: What Is an Asteroid?
• Article for Kids: Why Does the Moon Have Craters?
• Article for Kids: What Is an Impact Crater?

Explore More

• Facts & Figures: Didymos In Depth
• Facts & Figures: DART Mission
• Website: DART Mission
• Gallery: DART Mission Images and Videos
• Facts & Figures: Asteroid Watch
• Gallery: Next Five Asteroid Approaches
• Articles: Asteroid News and Images from JPL
• Eyes on Asteroids
• Eyes on the Solar System - DART Impact
• Quiz: Are You a Planetary Defnder?
• Center for Near-Earth Object Studies

TAGS: Asteroids and Comets, DART, near-Earth objects, planetary defense, Science, K-12 Education, Teachers, Educators, Parents, Teachable Moments, Asteroid TM

• 

  ABOUT THE AUTHOR

  Lyle Tavernier, Educational Technology Specialist, NASA-JPL Education Office

  Lyle Tavernier is an educational technology specialist at NASA's Jet Propulsion Laboratory. When he’s not busy working in the areas of distance learning and instructional technology, you might find him running with his dog, cooking or planning his next trip.