Why are they in a line? It's because the solar system is flat. I know, last week I outlined two experiments you can do to prove that the Earth is not flat. But the solar system really is flat.

This happens because the planets in our solar system essentially orbit the sun along the same line across a flat, disc-shaped plane in the sky known as the ecliptic, according to cosmic news site ...

For a few evenings around 28 February, every planet in the solar system will be visible in the night sky, thanks to a rare great planetary alignment. Here's how to make sure you don't miss this ...

For the dwarf planet candidate, one trip around the sun takes over 24,000 years. Its orbit challenges a proposed path for a hypothetical Planet Nine.

This process, called accretion, is how everything in the solar system – planets, moons, comets and asteroids – came into being. Telescopes can see young solar systems being born.

The Sun accounts for some 99.86% of the mass in our Solar System; of the remaining fraction of a percent, fully two-thirds is embodied in Jupiter, which itself contains more than 70% of the total ...

Astronomers posed over the past decade that dark comets, or objects that resemble asteroids but move like comets, may exist. Now, scientists have found a total of 14 of them.

Meet the surprising, oddball worlds moving around our solar system. From meteorites that impact Earth, to a moon that orbits backwards, to an imposter lurking in the asteroid belt, a variety of ...