1. Mars is the second smallest planet in our solar system (now that Pluto has gotten the boot). At 4,220 miles wide, it is about half the size of Earth.
3. Mars has two lumpy and misshapen moons, Phobos and Deimos, which may be asteroids that the planet captured. The moons have very different orbital periods so that a stargazing Martian standing on the planet’s equator would see Phobos rise and set twice each day, while Deimos would linger in the sky for more than 2 days before slowly setting.
4. Mars is currently host to seven different visitors from Earth: five spacecraft are orbiting the planet and two more are on its surface.
5. Mars has polar ice caps made up of frozen water and carbon dioxide. In the springtime, the carbon dioxide begins to melt and converts directly to gas, causing geyser-like eruptions that spew clouds of sand and vapor into the sky.
7. Occasionally Mars and Earth come closer to one another as they orbit the sun. Between May 18th and June 3rd 2016, Mars will be 46.8 million miles from the Earth. If you miss it this time around, the next close approach will be in July of 2018 when Mars will be even closer—just 35.8 million miles away!
8. One day on Mars (24 hours and 37 minutes) is about the same as one day on Earth (23 hours and 57 minutes). One Martian year, however, takes 687 Earth days!
9. Mars is much less dense than the Earth. Despite being half as wide, it has only 1/10 the mass.
10. The gravitational pull you would feel standing on Mars is only about 62% of what you feel on Earth. This mean that you would weight 62% less on Mars.
11. The atmosphere on Mars is mostly carbon dioxide with a little bit of Argon, Nitrogen, and other gases thrown in.
12. You can see Mars in the night sky. Look to the southeast in early summer and you’ll see it glowing red, just above Antares at midnight.
Photos: Mars: NASA Goddard Space Flight Center; Martian Moons: NASA/JPL-Caltech/University of Arizona; Mars in the Night Sky: NASA/JPL-Caltech