Are there 10 planets

These KBOs act a lot like spinning tops, Renu Malhotra, a professor of planetary sciences at LPL and co-author of the new study, said in the statement. It may sound a lot like the mysterious Planet Nine , but the researchers say the so-called planetary-mass object is too small, and too close, to be the same thing. Planet Nine lies to astronomical units AU from Earth, and its mass is about 10 times that of Earth. One AU is the average distance at which Earth orbits the sun — 93 million miles, or million kilometers.

Pluto orbits the sun at a maximum distance of just less than 50 AU. Percival Lowell established his observatory in Flagstaff, Arizona to look for intelligent life on Mars. Eventually it was used to find Pluto Credit: Alamy.

Enter a hypothetical new addition to our solar system — but not as it was thought of before. In , the same Mike Brown who had slain Pluto, together with his colleague Konstantin Batygin — also a professor of planetary science at Caltech — co-authored a paper proposing a massive planet , between five and 10 times the size of Earth. Their idea came from the observation that Sedna was not the only object out of place. It was joined by six others , and all of them are being pulled in the same direction.

There are also other clues, such as the fact that each is tilted on its axis in exactly the same direction. The pair calculated that the probability of all six objects being pulled in the exact same direction, with the same tilt by chance was just 0. Instead, they proposed that Planet Nine had left its ghostly imprint in the outer reaches of our solar system, distorting the orbits of the objects around it with its gravitational pull. Several years on, and the number of objects that fit the eccentric orbital pattern and tilt has continued to increase, "We now have around 19 overall," says Batygin.

Though no one has yet seen the hypothetical planet, it's possible to infer a surprising amount about it. Scientists have also hazarded a guess at its aesthetic — icy, with a solid core, like Uranus or Neptune.

Then there's the slippery question of where Planet Nine might have come from in the first place. So far, there are three main ideas. One is that it formed where it currently hides, which Batygin dismisses as relatively unlikely because this would require the early solar system to have stretched out as far as its distant refuge. There's also the intriguing suggestion that the ninth planet is actually an alien imposter, an object that was stolen from another star long ago when the Sun was still in the stellar cluster in which it was born.

Then there's Batygin's personal favourite, which he admits is also "not a complete slam dunk". In this scenario, the planet formed much closer to the Sun, at a time when the solar system was in its early stages and the planets were just beginning to coalesce out of the surrounding gas and dust. Of course, all this begs an obvious question — if Planet Nine is really there, why has no one seen it? For example, astronomers would normally be looking for a class of objects, such as a particular kind of planet.

Even if they're rare, if you survey a wide enough expanse of space, you're likely to find something. But hunting down a specific object such as Planet Nine is a whole different exercise. This 8. This is ideal, because the shadowy planet would be so far away, it's unlikely to be reflecting much light from the Sun.

However, there is one almost outrageously peculiar scenario in which the planet will never be found this way — it might not be a planet after all, but a black hole. The Subaru telescope in Hawaii has already spotted the most distant known object in our solar system, nicknamed "Farfarout", during a search for Planet Nine Credit: Alamy. While we're most familiar with the idea that planets exert a powerful gravitational pull, "there are other things that can generate it, which are more exotic", says Unwin.

Some plausible replacements for planet nine include a small ball of ultra-concentrated dark matter, or a primordial black hole. As black holes are among the most dense objects in the Universe, Unwin explains that it's entirely possible the latter could be warping the orbits of distant objects in the outer solar system.

By Jeff Hecht. These images of the newfound planet were taken in October , each about 90 minutes apart. The planet, circled in white, moves across a background of stars. Astronomers have found a tenth planet, larger than Pluto and nearly three times farther from the Sun as Pluto is today.

Temporarily designated UB, the new planet is the most distant object yet seen in the solar system, 97 times farther from the Sun than the Earth is.

It also is the largest body yet found orbiting in the Kuiper belt, the group of icy bodies including Pluto which orbit beyond Neptune. Nevertheless, it is possible to set limits on the planet's diameter:. Pluto is miles km wide. The planet's temporary name is UB A permanent name has been proposed by the discoverers to the International Astronomical Union, and they are awaiting the decision of this body before announcing the name.

Stay tuned! Jul 29, Astronomers have found a new planet in the outer reaches of the solar system. Recommended Articles.