When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns.Only eight planets call our solar system home. Or there might ...

The inner planet completes an orbit in 9.1 Earth days, the next planet out orbits in 13.6 days, the third in 20.5 days, the fourth in 30.8 days, the fifth in 41 days, and the outermost planet in ...

While most of the lore surrounding the "parade of planets" has been debunked, Rao wrote that skywatchers can expect an equipment-free view of Mars on June 3 around 4:00 a.m. ET, which will be ...

A 7-planet alignment will be visible in the skies Friday, weather permitting. Here's what to know and how to see the planetary alignment.