Test your knowledge on our solar system, from the biggest and smallest planets to the behemoth mountain on Mars. When you purchase through links on our site, we may earn an affiliate commission.

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 as a ...

LYNCHBURG, Va. (WSET) — If you're trying to get a beautiful look at the planets in our solar system, you're in luck. Between February 25 and February 28, all seven planets in our solar system will be ...

All of our solar system’s planets are lining up in the night sky at once this week. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known as a great ...

WASHINGTON (Reuters) -Scientists have identified an object about 435 miles (700 km) wide inhabiting the frigid outer reaches of our solar system that might qualify as a dwarf planet, spotting it as it ...

AMES, Iowa – An international team of astronomers has used nearly three years of high precision data from NASA’s Kepler spacecraft to make the first observations of a planet outside our solar system ...