Thursday, April 20, 2017
It seems like we hear about new exoplanet discoveries every day. It seems like the holy grail of astronomy these days is finding another planet which has the right ingredients for life. In our own Solar System, for example, the Earth is the only planet we believe has all of the ingredients for life which also exists in the so-called circumstellar habitable zone. This is more frequently referred to as the Goldlocks zone, and it represents the distance from the sun where liquid water can exist. For planets too close to the sun, the surface of the planet will be too hot, and water will simply boil away into the atmosphere. When it is too far, water will simply freeze. Finding these planets are tricky, because they are far enough away from their sun that they don't transit in front of it sun (with respect to Earth's point of view) often enough to be readily detected by telescopes. The astronomer would have to train his equipment on any given star for so long that catching the transit would be a matter of pure luck. Further, life-supporting rocky planets are likely to be so small that they are hard to see in front of the sun and even harder to detect its gravitational effects on its own solar system.
However, just days after publishing The Twisted Galaxy, scientists have revealed that they have discovered the most promising exoplanet for finding life. LHS 1140b is one of just a couple dozen super-Earths (planets reasonably larger than our own planet) sitting in the habitable zone of their respective stars. However, at 39 light years away, LHS 1140b is one of the closest known examples, meaning we might have a better chance at observing the makeup of the planet and determining its probability of hosting life.
While it's not 27,000 light years away, as is Earth2 in the Galaxy Series, it's nevertheless fun to watch astronomers catalog the increasing number of exoplanets as a way to improve the odds that intelligent life is not just found in isolation on our own little planet.