the brightest and the sixth biggest planet
People have only been to the moon. However, we can still see other planets using telescopes, satellites and probes.
It can see their weather changes that are similar to our planet Earth, it can also see the size and if there are aliens in other planets, like Mars
Stars The Moon The sun Galaxies Nebulae Satellites
The reason why some planets of satellites is because there are some planets that are capable of hosting many types of species (ie earth). There will be a more dominant species on that planet and due to their mass technology after millions of years of evolution and changes towards the planet; much like out planet, the dominant species will send off a random piece of metal junk to see if there are other species in the universe, or other scientific experimentation. We would call these Satellites.
Lots. See http://www.users.zetnet.co.uk/pete/Moons.htm
Planets, moons, asteroids, artificial satellites.
The word Moon is a name given to the natural satellite in orbit around the Earth. We attribute this name to most objects large enough to see in orbit around other planets. In this way Moons and Natural Satellites are one in the same. Artifical Satellites are what we put into orbit around the earth IE GPS Satellites, but are man made.
Actually some other planets do, but you can't see them. Like Uranus or Neptune. They have rings but they are very thin. And you could say the Earth has a ring of satellites around it.
I am not sure what exactly you mean with "planetary objects". To see planets, just look up in the evening, and watch out for objects that look like exceptionally bright stars. These days (October 2010), after sunset you can see Venus as a very bright star in the west, and Jupiter as a bright star (less bright than Venus, but otherwise exceptionally bright) in the east.
That is the correct spelling of "planet" -- a large object orbiting a star. In our solar system, planetary bodies are generally classified by size and orbits as planets, dwarf planets, moons, or asteroids.
Mars was created when the other planets were, around 4.6 billion years ago during the formation of our solar system in a process known as planetary accretion. Please see the related links.
they want to see why other planets are differant from earth and want to learn and study other planets!