Kaguya-hime and the Solar System 85
Size Approximately 0.53 times the size of Earth (equatorial radius of 2,110 miles,
or 3,396 km)
Mass Approximately 0.11 times the mass of Earth
Surface gravity Approximately 0.38 times the gravity of Earth
Satellites 2: Phobos and Deimos
Mean distance from the Sun 1.52 AU
Orbital period Approximately 687 days
Rotation period Approximately 1 day
What’s It Like There?
The surface of Mars is entirely desert, except for two polar ice caps. The planet has a thin,
carbon dioxide atmosphere. The existence of water there has been confirmed, and among
the planets of the solar system, its atmosphere is the most similar to Earth’s. Its highest
atmospheric temperature is approximately 68°F (20°C), and Kaguya-hime herself could
easily live there as long as she had an Apollo-type spacesuit.
The geological composition of Mars is also similar to that of Earth, and since the length
of one Mars day is also about the same as one Earth day, a person’s daily living patterns
would not be disrupted. However, since one of Mars’s two satellites, Phobos, revolves around
Mars faster than Mars rotates, it rises and sets twice each night.
Mars is the home of Olympus Mons, which is said to be the largest mountain in the
solar system. Its height is approximately 82,021 feet (25,000 m), which is approximately
three times the height of Mount Everest! Mars also has the largest canyon in the solar sys-
tem, and its terrain includes many plains.
Tornado-like whirlwinds sometimes blow across the surface of Mars. One of these was
photographed by the Mars Pathfinder spacecraft, which was launched by the United States
in 1996. In 2004, two robotic vehicles called Opportunity and Spirit landed on Mars. These
NASA rovers have made many important discoveries about Mars and have sent back more
than 133,000 images of the planet’s surface.
* Want to see those photographs and hear more about the Mars rovers? Visit http://marsrovers.jpl.nasa.gov/.