There may be hundreds of dwarf planets in our solar system
Far beyond Pluto, deep in the Kuiper Belt where the sun is barely more than star, a new dwarf planet was just discovered . And it may be one of hundreds waiting to be discovered.
Over the last few decades, the discovery of dwarf planets has been very much on the upswing. Along with Pluto, the number of confirmed dwarf planets in our solar system has grown to include Ceres, Eris, Haumea, and Makkemake – and now, 2014 UZ224.
The trans-Neptunian dwarf planet is roughly the size of Iowa, or half the size of Pluto, and it orbits the sun once every 1,000 years at a distance of 8.5 billion miles. It is rocky and generally spherical (a prerequisite for a dwarf planet), but beyond that, not much is known.
2014 UZ224 was discovered mostly by luck. Two years ago, University of Michigan astrophysicist David Gerdes challenged a group of visiting undergrads. He gave them a map of the galaxy filmed using a wide angle camera and told them to find objects in our solar system.
To do so, the students looked for objects close enough to be seen moving. Gerdes assumed they would spot one of the eight planets. Instead, they surprised him with a previously undiscovered dwarf planet. It took two years to confirm 2014 UZ224, which is the third most distant known object in our solar system. For now, at least.
While the number of known dwarf planets in the solar system is still relatively low, it will almost certainly rise, possibly into the hundreds.
As of October 11, 2016, there are 10 objects that are certainly dwarf planets, 29 objects that are highly likely to be dwarf planets, 74 objects that are likely dwarf planets, 146 objects that are probably dwarf planets, and 694 that are possibly dwarf planets.
Most of those objects are in the Kuiper Belt at the edge of the solar system, making them mostly out of reach. It is possible we could send a craft that deep into the solar system, but it would take years and a huge amount of money, so there would need to be a very good reason – something more than just the desire to get a closer look at a spherical rock hanging in space.
As for 2014 UZ224, there may still be some contention as to whether or not it actually meets the criteria of being a dwarf planet. It may not be spherical enough, it may not have cleared its orbit, and it may have failed on other fronts as well. For now though, it has the designation and will soon earn a name.
As for Gerdes, his team will continue the search for a much more tantalizing object – the undiscovered ninth planet in the solar system.