Artist's impression of a possible 9th planet, which could exist on the edge of the solar system. – CALTECH
Is a planet ten times more massive than the Earth hiding on the edge of the solar system? The hypothetical "planet X" (or planet Nine, for those who do not count Pluto) fantasizes many astronomers. The quest returns to the front of the stage this week, after the discovery of a distant transneptunian pebble, 2015 TG387, dubbed "the goblin". Its flat elliptical orbit could be due to the influence of a massive body located even further, say the researchers. At this stage, however, it is only a supposition, and no direct evidence of the existence of this famous "planet X" has so far been detected.
The very flattened orbit of a new transneptunian object called "the goblin" could, according to the author of the discovery, be due to the influence of the famous hypothetical "planet X". pic.twitter.com/UUE2KnHYhI- Philippe Berry (@ptiberry) October 2, 2018
"These distant objects are crumbs on the track of planet X. The more we find, and the better we understand the boundary of the solar system and the influence of a possible planet that, we think, shapes their orbit," writes Scott Sheppard. At the head of a team from the Carnegie Institution for Science, he observed this dwarf planet 300 km in diameter with the Subaru telescope located in Hawaii.
The displacement of this pebble about 300 km in diameter was observed 3 hours apart with the Subaru telescope located in Hawaii. pic.twitter.com/iY0qMXYuIV- Philippe Berry (@ptiberry) October 2, 2018
The turn of the sun in 40,000 years
This pebble is not alone. Two other similar objects discovered in recent years, including Sedna, also seem to be influenced by the gravity of an invisible body. The problem is that watching these dwarf planets directly is complicated. At close range, they approach 65-80 astronomical units of the Sun (1 AU = Earth-Sun distance) – it is 2.5 times further than Pluto. In the case of the "goblin", its elliptical orbit takes it further to 2,300 AU from our star. And it takes 40,000 years to go around.
According to the researchers, there could be thousands of similar distant objects. They hope to discover more, to be able to reduce the hunting grounds of the mythical planet X. The quest continues.