orbit of the planets The planets that orbit nearest the sun are somewhat like Earth. Mercury,Venus,and Mars are made up mostly of solid rock. Jupeter,Saturn,Uranus,and Neptune are very diffrent from Earth. The outer parts of these planets are made up of rock ice. You problythink that pluto is farthest from the sun . most of the time you are right! However, sometimes Neptune is farther from the sun than Pluto. This is beacause at times Pluto's orbits crosses Neptunes orbit. Between 1979 and 1999,Neptune was farthese from the sun.