Monroeville Public Library is holding a three-part children’s series on space, where participants learn fun facts about the ...

With a radius of 2,106 miles, Mars is the seventh largest planet in our solar system and about half the diameter of Earth. Its surface gravity is 37.5 percent of Earth’s. Mars rotates on its ...

Narrator: Further from the Sun, in the outer reaches of the solar system, we find the gas planets. Much larger than the rocky planets, these cosmic giants are accompanied by numerous moons.

This may explain the strange properties of the orbits of our solar system's planets, which are not quite perfectly circular, and all lie on slightly different planes. NASA artist’s conception of ...

If everything in our solar system formed from the same solar nebula, why do the planets have different compositions? Herbert Wich Titusville, Florida To better understand why the planets have variable ...

Stargazers will be treated to a rare alignment of seven planets on 28 February when Mercury joins six other planets that are already visible in the night sky. Here's why it matters to scientists.

While the planets won’t be perfectly aligned, their placement will follow the orbital plane of our solar system. Which planets are parading in January and February? The January planetary ...

The seven planets will not be perfectly aligned, but will appear in an arc across the sky due to their orbital plane in the Solar System. The world will witness a rare sighting in the sky in late ...