Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to ...

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event ...

But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might still be nine if some astronomers are correct about an as-yet ...

The stars may not be aligning on Friday night, but seven planets in our solar system just may be. For weeks, outer space enthusiasts have been gearing up for a planetary alignment, or "planetary ...

Our solar system ... the outskirts of the solar system is the activity within the Kuiper Belt, an unusual clustering of icy bodies -- including comets and dwarf planets -- which stretches from ...