Testing of Mars Landing Radar near Lancaster, Calif.

Dawn Orbiting Vesta

Mars Sample Return Spacecraft Before Arrival (Artist's Concept)

How Phoenix Talks to Earth

Phoenix Extends its Legs

Artist's Concept of Mars Exploration Rover

Moving Juno to Environmental Testing

Schematic of Laser-Induced Breakdown Spectroscopy

Light Travels Through AIRS Optics

Weighing Planetary Disks

An Astronomer's Fantasy: Planets in the Lab

Diviner Undergoing Post Thermal Vacuum Range of Motion Testing

Illustrating MastCam Capabilities with a Terrestrial Scene

NASA Mars Rover Curiosity at JPL, Side View

Mars Rover Curiosity in Artist's Concept, Close-up

Webb Instrument Undergoes Alignment Testing

Vega: Two Belts and the Possibility of Planets

NASA's Salt-Seeking Instrument Gets a Silvery Blanket

NuSTAR Inches Toward its Rocket

Juno Gets Ready to Shake It

Simulating a Submarine Hydrothermal Vent

Preparing Juno for Environmental Testing

Phoenix Without its Parachute

'Y Dwarf' Chillin' in Space (Artist's Concept)

Mars Science Laboratory Powered Descent Vehicle

Anatomy of Brown Dwarf's Atmosphere (Artist Concept)

Installing Juno's Radiation Vault

Cruise Stage Testing for Mars Science Laboratory

Kepler's Planetary Systems in Motion (Artist Concept)

Mars Science Laboratory and Its Payload Fairing

Juno Above Jupiter's Pole (Artist's Concept)

Three Eclipsing Bodies (Artist Concept)

Curiosity While on Parachute, Artist's Concept

Wheels Spinning

Engineers Test Roll-Off at JPL

MAVEN at Mars, Artist's Concept

Coronation's Chemicals

NASA's WISE Spacecraft in Protective Covering

Two X-Ray Observatories are Better Than One

Landing Accuracy on Mars: A Historical Perspective

Three Generations in Mars Yard, High Viewpoint

Mast Camera View of Curiosity's Deck

Phoenix's Path to Mars

Curiosity Pre-Launch Mast Test - August 07, 2012

Second Test Rover Added for 'Free Spirit' Tests

NuSTAR's Russian Doll-like Mirrors

View Down the Barrel of NASA's WISE Telescope

Primary Structure for MAVEN Spacecraft

Installation of Curiosity's Wheels and Suspension

Aquarius - SAC-D (Artist's Concept)

Close-up of Diviner Solar Calibration Target