Beautiful and mysterious, peaceful and serene, the moon is the brightest object in the night sky. Jupiter and Saturn have more than sixty moons each. Neptune has thirteen moons. Even Mars has two moons. But the Earth, our planet, only has one moon, our nearest neighbor in space. Even though the moon is close to us when compared to other planets, it is still very, very far away. The moon is about 239 thousand miles or 384 thousand kilometers away. You would have to travel all the way around the Earth nine and a half times to go the same distance as the space between the Earth and the Moon. The moon is much smaller than the Earth. Ifthe Earth was hollow, about fifty moons could fit inside. Because it is so much smaller than the Earth, the moon's gravity is much weaker. This means that if you were to visit the moon, you would weigh much less than you do on earth, only about 1/6th of your current weight. That means that if a giraffe was on...
Mars: the fourth plant from the sun, is the second smallest planet in the solar system, larger only than Mercury. Mars, as one of the five planets visible to the unaided eye, has been known to astronomers since ancient times: it was first recorded by ancient Egyptian astronomers about 4,000 years ago.
Mars is often called the Red Planet, because of its reddish color. Modern astronomers know that Mars is red because of large amounts of iron oxide, or rust, in the rocks and dust on the surface, but in ancient times people associated its red color with warfare. That is why Mars was named for the ancient Romangod of War.
Mars is a small, rocky planet, the last ofthe planets of the inner solar system. It is about 141 million miles, or more than 227million kilometers from the sun, so it gets less than half as much sunlight as the earthdoes.
Temperatures at the frozen poles may dip as low as negative 225 degrees Fahrenheitor negative 143 degrees celcius, but at the equator it may get as warm as 95 degrees fahrenheitor 35 degrees celcius. One reason that Mars has such different temperatures is that whileit has an atmosphere - made mostly of carbon dioxide, with tiny amounts of oxygen - it is very thin, preventing it from holding onto much energy from the Sun.
Mars has two moons, Phobos and Deimos. Compare to Mars, or even our own moon, they are very, very small: Phobos, the larger of the two,is only 14 miles, or 22 kilometers, across at its widest point, which means you couldset it down inside Rhode Island and still have plenty of room to add Deimos. Because they are so small, they don't have enough gravity to pull themselves into spheres, and so Phobos and Deimos are lumpy and irregular. Scientists believe that they may be stray asteroids captured by Mars' larger gravity at some point in the past.
Something interesting about Mars is that it is home to the highest known mountain in the Solar System - Olympus Mons! Olympus Monsis more than three times higher than the tallest mountain on Earth, Mount Everest. It's sotall that it nearly reaches the top of Mars' thin atmosphere. There is no liquid water on Mars, but thereare two polar ice caps made of large amounts of frozen water, and sometimes there are even clouds made of water vapor, much like on Earth.
A day on Mars is very close to the same lengthas a day on Earth, too. Mars rotates in 24 hours and 37 minutes, only about 2.7% longerthan an Earth day. Because Mars is farther from the sun, however, Mars takes much longer to travel once around the sun than Earth does, almost 687 days. Because Mars is so close to the Earth and is so similar in some ways, people have wondered for a very long time if life could survive there - or if something lived on Mars already. Back in 1877, astonomers thought they saw canals on the surface of Mars in long, straight lines.
If there were canals, they thought, someone must have made them. People wrote books and stories about aliens from Mars,and they called them 'Martians.' Modern astronomers have not found any signs that anyone or anything has ever lived on Mars. If there was ever life on Mars, it was probably only small, simple kinds of life, like bacteria.
Now people wonder if Mars couldbe made into a good place for humans to live. More than 50 space missions have been sentto or close to Mars to gather more information about this fascinating red planet. There are currently five orbiters circling Mars, and two rovers exploring its surface, all sending data back to Earth. People want to try to go to Mars someday, and it may happen in the next few decades. Until then, there is always more to learn about this exciting planet.
I hope you enjoyed learning more about Mars.
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