Chalk another one up to NASA's Kepler Mission. The Agency's team of planet-hunters announced yesterday the discovery of 11 new planetary systems, which together harbor 26 brand spanking new planets.
For those you keeping score at home, that brings the total number of Kepler-confirmed extrasolar planets from 35 to 61, and almost triples the number of verified, multi-planet star systems, raising that number from 6 to 17.
And if you think that sounds impressive, remember: Kepler is just getting warmed up. With over 2,300 exoplanets in the wings still awaiting confirmed-planet status (and new candidate planets being discovered all the time), many astronomers believe it's only a matter of time until Kepler achieves that which it was designed to do: discover Earth-like planets orbiting within the life-permitting "habitable zones" of other star systems (assuming, of course, that we haven't already found one).
This chart depicts all the multi-planet systems discovered and confirmed by NASA's Kepler mission to date [click the image for the hi-res version]. The newest inductees are depicted in green, while the planets from our own solar system are represented in blue, over in the leftmost column.
This video provides an overhead view of the multi-planet star systems discovered by the Kepler mission. According to NASA, all the planets — with the exception of the ones labeled in grey — have been officially confirmed.
This video also serves as a good introduction to an exoplanet-hunting technique you may not be familiar with. First, check out the incredible variation in the planets' orbital periods (how long it takes each planet to make one complete trip around its sun). Since Kepler detects candidate planets by measuring dips in detectable light as one passes in front of — or "transits" — a distant star, having more than one planet in any given star system can give rise to some pretty crazy measurements. According to NASA:
In tightly packed planetary systems, the gravitational pull of the planets among themselves causes one planet to accelerate and another planet to decelerate along its orbit. The [changes in acceleration cause] the orbital period of each planet to change. Kepler detects this effect by measuring the changes, or so-called Transit Timing Variations (TTVs).
The animation featured here illustrates how a densely packed planetary system can give rise to measurable transit timing variations. If you look back at the planetary systems in the first video, you'll notice that some of the planets are labeled with particularly vibrant colors. This indicates that the planet was verified by its gravitational interactions with nearby celestial bodies.
Read more about the Kepler Team's announcement on NASA and the Kepler Homepage.
Kepler Multi-Planet Chart by Jason Steffen/NASA Ames via; Planetary Systems video by Dan Fabrycky via NASA; Transit Timing Variations video by Kepler mission via NASA