Two new discoveries, one at the farthest boundary of our solar system, and one orbiting a dim star 39 light years add to a remarkable week of planetary news.
First up is V774101, a 300-600 mile diameter world discovered orbiting at a distance 3 times further out than Pluto, and 103 times further than Earth is from the Sun. It will take a series of follow up observations to determine if it as a member of the Oort Cloud, or instead a much closer but still distant Kuiper Belt Object which happens to have an unusual orbit. Even more interesting is how it got there, with one possibility being that it is an ancient moon left stranded in the outer reaches of our solar system by a ejected planet.
At the other end of the spectrum is GJ 1132b, a rocky planet only 16% larger than Earth, which was discovered orbiting a star in the cosmic neighborhood, a mere 39 light years away. It is the closest rocky planet yet discovered, an event which came about in part because it orbits so close to its own sun (1.4 million miles), a cycle which takes only 1.6 Earth days to complete. As one might expect, it is a rather toasty place, with an estimated temperature of 500 degrees Fahrenheit. Still, astronomers expect to confirm that it does have an atmosphere, making it a near analogy to Venus.
Given the relative proximity, GJ 1132b is likely to be a prime early target for the James Webb Space Telescope once it finally launches in 2018, and could in its own way help to refine the search for a the real prize, a water world much like ours.