The "Pi in the Sky" math challenge gives students a chance to take part in recent discoveries and upcoming celestial events, all while using math and pi just like NASA scientists and engineers. In this problem from the 10th set, students use pi to determine the volume of a rock core collected by the Perseverance Mars rover.



The Perseverance rover approaches a lander on the surface of Mars. A small rocket flies toward an orbiter overhead while a Mars helicopter flies in the background. A partially illuminated Earth appears in the distnace.

This illustration shows a concept for multiple robots that would team up to ferry to Earth samples of rocks and soil being collected from the Martian surface by NASA's Mars Perseverance rover. Image credit: NASA/JPL-Caltech | › Full image and caption

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.


Tubular Tally

The Perseverance Mars rover is designed to collect rock samples that will eventually be brought to Earth for further study. This would be the first time we've ever brought back samples from Mars! After scientists identify an interesting rock they would like the rover to collect, Perseverance uses a special coring bit to drill out a rock cylinder 13 mm in diameter. As the rover drills, the rock core moves into one of 38 available tubes that will store the rock sample – sealed until it is opened one day in a lab on Earth.

If the coring bit collects a rock cylinder 60 mm in length, what is the volume of the rock in the sample tube?

› Learn more about the Mars Perseverance rover

The center of the image shows an illustration of the Perseverance Mars rover with its robotic arm stretched out to the right, touching a rock on the ground. An inset in the lower right shows a cutaway of a coring bit filled with a rock sample measuring 13 mm wide and 60 mm tall. In the lower left a sealed sample tube is shown on the ground next to the rover. A thought bubble showing hands holding a sample tube is coming from the top of the rover's mast. The text of the Tubular Tally problem is shown on the left.

Image credit: NASA/JPL-Caltech | + Expand image


Illustrated answer key for the Tubular Tally problem.

Image credit: NASA/JPL-Caltech | + Expand image

Download text-only answer key (Google Docs)



Join the conversation and share your Pi Day Challenge answers with @NASAJPL_Edu on social media using the hashtag #NASAPiDayChallenge

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