Like the other inner planets, Mars does not have any rings. It does have two moons called Deimos and Phobos. The first astronomers looking at Mars could see the moons. They also saw polar caps and markings on the surface that looked like man-made canals. Many people believed for a long time that this meant there was intelligent life on Mars.
Scientists now know there is no surface water on Mars. At one time there may have been water flowing on the planet. Now the only water on Mars is in the air as water vapor, or frozen under the soil and at the poles. The Mariner 9 space probe showed that the canals, now called channels, were formed naturally.
