We’ve observed the toxic atmosphere of a super-Earth 40 light years away.
Altered Carbon
Yesterday I talked about the 55 Cancri system, a Sun-like star which has at least four gas giant planets, two of which orbit the star much closer than Mercury in our own system. What I didn’t talk much about is the other known planet in the system, known as 55 Cancri e. It is a super-Earth with a mass about 9 times that of Earth’s. What we find is that its density is only slightly higher than Earth’s. This means it is likely a new kind of planet.
Battle of the Planets
The 55 Cancri system is in some ways very similar to our own. The star is about the same mass and size as our Sun, and it has a Jupiter-sized planet at a distance of 5.7 AU, which is just slightly more distant than Jupiter’s 5.2 AU distance. It has three other gas planets, as well as a super-earth. One would think that the system might be similar in other ways, such as having rocky planets close to the star and gas planets more distant. But this is not the case.