Four years ago, I was boggled to realize that astronomers had been finding planets around other stars at an average rate of one per month since the first exoplanet around a main-sequence star was discovered in 1995.
On Monday, scientists from the European Southern Observatory (ESO) announced that they had found 32 new exoplanets in recent work. Moreover, that brings the total found to roughly 400. Instead of discovering a new planet every month, the average is now much closer to every two weeks.
What is the goal? The astronomers announced their findings at a conference titled, “Towards Other Earths: perspectives and limitations in the [Extremely Large Telescope] era.” The ESO instruments have led to the detection of 24 of the 28 known exoplanets with masses of less than 20 times the earth’s. The technology to spot earth-like planets around other stars is either on the drawing board or under construction. Key puzzles are now in how to characterize atmospheres around exoplanets, and how to deduce other characteristics of earth-like planets that the astronomers expect to find.
And in two weeks, astronomers will likely have found another planet around a different star.