• Mars is just a smidgen over half as big as Earth (53%). If Earth is a big, blue wiffle ball, Mars is a small, red ping-pong ball.

  • Mars is named after the Roman god of War because of its reddish color. The red color comes from rust! Martian dirt has lots of iron in it, which has rusted over time. That dust gets kicked up into the atmosphere and makes the planet look red even from far away. But Mars has lots of other colors, too. Dig deep enough and Mars has blue and green rocks that haven’t rusted yet.

  • Mars has not one but two moons, and both are teeny tiny, much smaller than our Moon. They’re named Phobos and Deimos, after the two horses that pulled the god of war’s chariot. They’re lumpy like potatoes. (The moons, not the horses.)

  • How far away from Earth is Mars? It depends! Mars and Earth both orbit around the Sun, but they move at different speeds, and their orbits are stretched circles called ellipses, so sometimes they’re farther away from each other, and sometimes they’re closer together. Depending on when you ask, Mars could be anywhere from 33.9 million miles away to 250 million miles away.

  • Mars takes so long to go around the Sun that one Martian year is almost two Earth years. And you think your birthday takes forever to get here.

  • Martian sunsets are blue! Sunrises, too! On Earth, sunsets and sunrises are often red and orange because of our atmosphere. Martian atmosphere is much, much thinner, but it’s filled with lots of very tiny dust particles that reflect the sun’s red light back and let more blue light come through.

  • Astronomers used to think Mars was inhabited with cities and people, just like Earth. They thought they saw canals with water. Now we know there are no running rivers, no cities, no Martians. But that doesn’t make the planet any less beautiful or interesting.

  • Some interesting places to visit on Mars:

    • Olympus Mons, the largest volcano in the entire solar system and highest point on Mars.

    • Hellas Planitia, a massive crater from when something large struck Mars long ago. It is also the lowest point on Mars.

    • Valles Marineris, a huge canyon so long that it could stretch across the middle of the United States of America from one coast to the other. If you find North Carolina on the map and walk your fingers straight over to California, that’s the Valles Marineris.

    • The North and South Poles, which, like on Earth, are the coldest points on Mars and also are covered in ice. Unlike Earth, Mars’s ice isn’t just water ice. The Poles also have frozen carbon dioxide, which you can buy at the store as “dry ice.”

    • Galle Crater, also known as the Happy Face Crater because of its shape.

    • Perseverance Valley, part of Endeavor Crater and Opportunity’s final stop. One year after Opportunity's end, people from around the world voted in an online poll and Oppy’s little sister was officially named—Mars Rover Perseverance.





Two months after Oppy’s final message, NASA created a portal on their website where fans from all around the world could send digital postcards to the rover to encourage her to wake up. You can still read them online here:






  • A is for Astronaut by Clayton Anderson, illustrated by Scott Brundage (Sleeping Bear Press)

  • The Boy Whose Head Was Filled with Stars: A Life of Edwin Hubble by Isabelle Marinov, illustrated by Deborah Marcero (Enchanted Lion Books)

  • Birthday on Mars! by Sara Schonfeld, illustrated by Andrew J. Ross (Penguin Workshop)

  • Classified: The Secret Career of Mary Golda Ross, Cherokee Aerospace Engineer by Traci Sorell, illustrated by Natasha Donovan (Millbrook Press)

  • A Computer Called Katherine: How Katherine Johnson Helped Put America on the Moon by Suzanne Slade, illustrated by Veronica Miller Jamison (Little, Brown Books for Young Readers)

  • Counting the Stars: The Story of Katherine Johnson, NASA Mathematician by Lesa Cline-Ransome, illustrated by Raúl Colón (Simon & Schuster/Paula Wiseman Books)

  • Curiosity: The Story of a Mars Rover by Markus Motum (Candlewick)

  • Dark Was the Night: Blind Willie Johnson’s Journey to the Stars by Gary Golio, illustrated by E.B. Lewis (Nancy Paulsen Books)

  • Destination: Mars by Seymour Simon (Collins)

  • Earthrise: Apollo 8 and the Photo That Changed the World by James Gladstone, illustrated by Christy Lundy (Owlkids)

  • Fly High, John Glenn: The Story of an American Hero by Kathleen Krull, illustrated by Maurizio A.C. Quarello (HarperCollins)

  • The Girl Who Named Pluto: The Story of Venetia Burney by Alice B. McGinty and Elizabeth Haidle (Schwartz & Wade)

  • Heart on Pluto by Karl Jones, illustrated by Andrew J. Ross (Penguin Workshop)

  • Hidden Figures: The True Story of Four Black Women and the Space Race by Margot Lee Shetterly, illustrated by Laura Freeman (HarperCollins)

  • I Am Neil Armstrong by Brad Meltzer, illustrated by Christopher Eliopoulos (Dial Books)

  • Listening to the Stars: Jocelyn Bell Burnell Discovers Pulsars by Jodie Parachini, illustrated by Alexandra Badiu (Albert Whitman & Company)

  • Look Up!: Henrietta Leavitt, Pioneering Woman Astronomer by Robert Burleigh, illustrated by Raúl Colón (Simon & Schuster/Paula Wiseman Books)

  • Mae Among the Stars by Roda Ahmed, illustrated by Stasia Burrington (HarperCollins)

  • The Magic School Bus: Lost in the Solar System by Joanna Cole and Bruce Degan (Scholastic)

  • Mars!: Earthlings Welcome by Stacy McAnulty, illustrated by Stevie Lewis (Henry Holt and Co.)

  • Moon's First Friends: An Educational and Heartwarming Story About the First Moon Landing by Susanna Leonard Hill, illustrated by Elisa Paganelli (Sourcebooks Wonderland)

  • My Journey to the Stars by Scott Kelly, illustrated by André Ceolin (Dragonfly Books)

  • Red Rover: Curiosity on Mars by Richard Ho, illustrated by Katherine Roy (Roaring Brook Press)

  • She Caught the Light: Williamina Stevens Fleming: Astronomer by Kathryn Lasky, illustrated by Julianna Swaney (HarperCollins)

  • The Stars Beckoned: Edward White’s Amazing Walk in Space by Candy Wellins, illustrated by Courtney Dawson (Philomel Books)

  • The Stuff Between the Stars: How Vera Rubin Discovered Most of the Universe by Sandra Nickel, illustrated by Aimée Sicuro (Harry N. Abrams)

  • Voyage through Space by Katy Flint, illustrated by Cornelia Li (Wide Eyed Editions)





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          Mathewson, Samantha. “Send NASA's Mars Rover Opportunity Support As It Battles Epic Dust Storm.” Space.com,              Space, 31 Aug. 2018, www.space.com/41698-mars-rover-opportunity-dust-storm-support.html

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“NASA's Opportunity Rover Rolls Free on Mars.” Mars Exploration Rovers, NASA, 6 June 2005,                                                              mars.nasa.gov/mer/newsroom/pressreleases/20050606a.html

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“Opportunity: Making Tracks on Mars.” YouTube, NASA Jet Propulsion Laboratory, 22 Jan. 2010,                                                            www.youtube.com/watch?v=YcXelcgGMIY

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