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 fact that our solar system has eight planets (unless you’re a Pluto apologist) is one of the first things we learn in our educational journey (anyone remember the “Blue’s Clues” planet song?). But ...

The solar system is 4.54 billion years old, based on rock dating. Gas giants (Jupiter and Saturn) likely formed first. Ice giants (Uranus and Neptune) probably formed next. Rocky planets formed last, ...

An artist’s rendering of the theorized Planet Nine, back towards the sun. The planet is thought to be gaseous, similar to Uranus and Neptune. Hypothetical lightning lights up the night side. We get a ...

Which planet is the furthest from the sun? Some may think it’s Pluto, but it’s actually Neptune. Learn more about this ice giant and how it can help us understand more about planets in our Solar ...

Mercury is the innermost and smallest of the eight major planets in our Solar System, orbiting closest to the Sun. Though ...

Carbon dioxide has been detected on a planet outside our solar system for the first time. The gas has been observed directly by the James Webb Space Telescope on four exoplanets, all belonging to the ...