Why are outer planets gaseous in nature whereas inner planets in our solar system are rocky?

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, from innermost to outermost.

is one of about 200 billion stars (or perhaps more) within the Milky Way Galaxy. So far, astronomers have found more than 500 solar systems and are discovering new...

Other planet data are Mercury 0.01 degree Venus 177.4 degree(reverse direction) Mars 25.2 degree Jupiter 3.1 degree Saturn 26.7 degree Uranus 97.8 degree Neptune 28.3 degree.

The inner planets (Mercury, Venus, Earth, Mars) formed by accretion from heavy elements like iron, nickel, and silica. Thus, they tend to have solid core, mantel and crust to them....

When the solar system formed, did too, and there is not much difference between the respective ages of the planets. All formed within a million-billion years after the solar system...

Our solar system is moving along with the galaxy of course. It is also moving, though rather slowing, within the galaxy. We do not have a good grasp of other...

A solar system is when one or more planets revolves around a star of any kind. The universe is full of solar systems, because stars are almost always big enough...

Wobbling, transit methods can only find large planets,..Directs observation is also difficult..When planet isvfar away the periods are very long and difficult to watch with the present day technology..

Plate tectonics requires a particular kind of interaction between a more solid outer crust - lithosphere - and a more fluid inner layer - asthenosphere. Some geological features on Mars...

Less dense substances float on more dense substances. An ocean contains sea water, which contains dissolved salts and other solutes. The average of sea water is $"1.027 g/cm"^3"$, so the...