The Planets and Space Exploration
The four planets
at the center of the solar system are solid, rocky bodies like the
Earth. They include Mercury, Venus, and Mars.
Jupiter,
Saturn,
Uranus, and
Neptune are all made mostly of
gas and are
called giant planets because they are so large compared to Earth.
Their are several dwarf planets that are much smaller than Earth. Pluto, Haumea, Eris, Makemake, and the asteroid Ceres are all dwarf planets.
Unmanned spacecraft have traveled to all the planets in the solar system and
taken pictures of the planets and many of their moons. They have also
taken measurements that tell us what the planets are like inside.
Big, Bigger, Biggest
A Solar System Model Builders Guide
You might also be interested in:
In 2006 the International Astronomical Union (IAU) approved a new classification scheme for planets and smaller objects in our Solar System. Their scheme includes three classes of objects: "small solar
...morePluto is a frigid ball of ice and rock that orbits far from the Sun on the frozen fringes of our Solar System. Considered a planet, though a rather odd one, from its discovery in 1930 until 2006, it was
...moreEris is a dwarf planet in our Solar System. Eris is a lot like Pluto, which is also a dwarf planet. Eris and Pluto are both very far from the Sun. They are both very, very cold. Eris was discovered in
...moreMakemake is a dwarf planet in our Solar System. Makemake was discovered in March 2005 by a team of astronomers led by Mike Brown. Makemake officially became a dwarf planet in July 2008. There were three
...moreThe solar system is made up of the Sun, the // Call the planets count function defined in the document head print_planet_count('planets'); planets and // Call the planets count function defined in the
...more Scientists believe that the solar system was formed when a cloud of gas and dust in space was disturbed, maybe by the expl osion of a nearby star (called a supernova). This explosion made waves in space
...moreDo you know what a planet is? Guess what... astronomers are not quite sure what a planet is! Mercury, Venus, Earth, and Mars are the planets closest to the Sun. They are definitely all planets. They are
...more