The Inner Planets

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When I was growing up, there were nine planets in the solar system. To my knowledge, there was no such thing as dwarf planets, but only asteroids and comets along with the planets and the moons. Today, there are eight known planets in the solar system with the addition of tens to hundreds of tiny small bodies, known as dwarf planets.

The sun, the center of our piece of the cosmos, makes up about 99.8 percent of the solar system’s mass. That means, that all the planets, moons, asteroids, comets, and everything else you could possibly imagine ends up being .2 percent of the mass. That’s an incredible, almost unhuman like concept to fathom.

Closest to the sun, also referred to as the inner planets - Mercury, Venus, Earth, and Mars - are also commonly known as the rocky planets. These bodies are composed majority of iron and rock. Venus, the second planet from the sun could be called Earth’s sister. They’re roughly the same size, and if not for the gaseous clouds that reside in its atmosphere, could possibly harbor life. Actually, at the moment, there’s probably some chance that some sort of microbes are already or could possibly be living there now. That’s has a chance at about as much mass as all objects besides the sun has, .02 percent. The only planets that have natural satellites in the inner planets are the Earth, which has the moon, and Mars who is orbited by Phobos and Deimos. These two moons were most likely captured by Mars's gravity as they were orbiting around in the asteroid belt.

Between Mars and Jupiter lies the asteroid belt. A group of rocks stuck in an orbit held by Jupiter and the Sun pulling on them from opposite directions. Within this belt is where the majority of our dwarf planets are contained. There’s Ceres, about 590 miles in diameter and is currently being orbited by the Dawn spacecraft. What makes Ceres so unique and interesting is the fact that there are large white patches that reflect light and no one really knows what this is. There’s also the possibly that water may be residing in it’s craters or beneath the surface. There are other smaller dwarf planets in the asteroid belt, however, none are truly special enough to mention in this posting.

We have roughly explored the inner workings and make-up of the four rocky planets, along with the asteroid belt and it’s habitants of dwarf planets. Next we will begin to explore the wondrous and gigantic world of the the outer planets and taking a look at the beauty these planets hold.