Quick! Identify this image:
Although they may look like speckled eggs, these are alien worlds: a few of the 1,235 exoplanet candidates identified since 2009 by NASA’s Kepler observatory. Before Kepler, about 500 exoplanets total had been discovered, painstakingly, one-by-one, over more than a decade–which demonstrates how dramatically the pace of discovery increases as new tools come online.
The “eggs” above are stars arranged in size order. The “speckles” are planets in silhouette. The entire image, created by a scientist named Jason Rowe, can be seen here.
On this scale, our own sun (occluded by Jupiter and Earth) would look like this:
Based on the information the Kepler project has gathered so far, astronomers are estimating that there may be as many as 50 billion planets in the Milky Way galaxy with 2 billion of those being about the size of Earth, about 10 million of which might be in a range to hold liquid water necessary for the development of life.
If you’d like to participate in your own Easter egg hunt in space, check out Planethunters.org for a chance to be part of a crowdsourced project using Kepler data to find some of the exoplanets that Kepler’s automated algorithm may have missed.
–Greg R. Fishbone, hard boiled