You may be thinking, "Wait a minute, I thought there were a total of nine planets!" ... Here is a list of the eight planets in order starting with the nearest planet to the Sun. Advertisement.

If Planet Nine is ultimately detected, it would mark a monumental addition to our understanding of the solar system. More information: Terry Long Phan et al, A Search for Planet Nine with IRAS and ...

Planet Nine: A planet search at solar system's edge. The hypothesized Planet Nine is estimated to be about 10 times the mass of Earth (Image credit: ESO/Tom Ruen/nagualdesign) ...

Planet Nine, seen in this illustration, might be one of two additional worlds in our solar system. Caltech/R. Hurt (IPAC) Get the Popular Science daily newsletter💡 ...

If Planet Nine is ultimately detected, it would mark a monumental addition to our understanding of the solar system. More information: Terry Long Phan et al, A Search for Planet Nine with IRAS and ...

Astronomers have found new evidence that a mysterious ninth planet may be hiding at the edge of the solar system - rewriting what we know about the cosmos again.. An international team from Taiwan ...

Viewed in this longer context, the previously modern idea of having nine planets, which came about in the 1960s and lasted only until 2006, was a blip on the screen.

If Planet Nine is out there, this telescope might actually find it A powerful new observatory is the best hope yet for finding the elusive Planet 9, ...