Four planets will be widely visible to the naked eye through part of February, but calling them a 'planetary alignment' may not be the full picture.

A planet parade is when several of our solar system's planets are visible in the night sky at the same time. There will be six planets visible this time around, including Venus, Mars, Jupiter ...

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known ...

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 ...

While the composition of gas and dust in a molecular cloud is fairly uniform, everything changes once a star begins to form.