The search for a possible ninth planet in our Solar System has intensified in recent months, with more astronomers as well as amateurs joining in the hunt. Previous studies have hinted at its existence, but actually finding it has remained an elusive task. Now, astronomers from The Australian National University (ANU) are investigating four unknown objects in the outer Solar System that could be viable candidates for the mystery planet.
For the most part, the Solar System seems to be a rather well-ordered place; the planets, dwarf planets, and asteroids keep circling the Sun in regular orbits, the moons keep orbiting the planets, and so on. There are exceptions, however, such as how Uranus rotates “on its side” as compared to other planets and how Venus rotates in the opposite direction to most other planets. Now, astronomers have discovered another similar oddity, in the outer fringes of the Solar System: a small, asteroid-like object whose orbit is not only highly tilted against the orbital plane of the planets, but is also orbiting backwards compared to them. And it’s not alone. It appears to be part of a larger group of objects all doing the same thing. Weird…
The announcement of a possible large ninth planet in our Solar System way beyond Neptune last month caused a lot of excitement, needless to say. If confirmed, it may be similar to “super-Earth” type exoplanets which have been found to be plentiful around other stars, although none, that we knew of, around ours. At this point, however, it is still a well-presented theory. Now, there’s another possibility which has been offered to explain the weird orbits of some of the small Kuiper Belt objects – not a large planet, but rather a second Kuiper Belt consisting of many smaller objects instead.
For a long time now, there have been theories and rumors regarding the possible existence of another planet in our Solar System, far beyond Neptune or even Pluto, often referred to as “Planet X.” Unfortunately, there has been little hard evidence to back up any claims made. But now, new evidence has been presented by astronomers at Caltech which increases the likelihood of another, and fairly large, distant planet in the far outer reaches of the Solar System. How does this compare to other discovery claims for Planet X?
To say that 2015 has been a great year for planetary exploration would be an understatement, with fantastic new discoveries from around the Solar System. From our first ever close-up look at Pluto and its moons, to more evidence for ancient lakes and rivers on Mars (and current briny streams) to weird bright spots and mountains on Ceres, to the continuing study of Saturn and its moons, notably Enceladus, to spectacular close-up views of a comet, it has indeed been quite a year.