There's been a lot of noise, especially on social media, about a possible 9th planet being found in the solar system.
Is it real? What's the evidence? And is this a new thing?
The ancient Greeks only knew about 5 planets: Mercury, Venus, Mars, Jupiter, and Saturn.
Then in the late 1700s, William Herschel used a new telescope technology to find Uranus. But a wobble in its orbit suggested the presence of another planet...
Using this wobble, mathematicians calculated the position of this 8th planet in 1847, and Neptune was discovered. It was the only planet discovered by math.
Today, astronomers have discovered several asteroids from the Kuiper Belt that have very similar elliptical orbits through the solar system that are so close that it is only a 1 in 15,000 chance of happening at random.
And they are using similar math to map the location of a 9th planet, but one that is very different from the ones we know. This planet would orbit far outside our current solar system and would take 15,000 years to orbit.
Time will tell whether this proposed planet will be found, but scientists studying the phenomenon at the Subaru Observatory in Hawaii believe they'll have an answer in 5 years.