First, to be perfectly clear, we’re dealing with a pair of brown dwarfs here — which are still stars after all, although admittedly they inhabit the somewhat vague terrain between conventional stars and large exo-planets (more on that in this Sky and Telescope article). But there’s something particularly arresting about this pair of diminutive objects, at least distance wise.
Which is: they’re located a mere 6.5 light years away.
And that makes them the third closest known star system to us.
The closest known star to us happens to be a four star system. Alpha Centauri A and B (or Rigel Kent) is located 4.4 light years away, and its twin companion, Proxima Centauri (Ca, Cb), is slightly closer at a distance of 4.2 light years. Second closest is the restless and rapidly moving Barnard’s Star, at a distance of six light years.
Tempting as it may be to race out under the stars with a telescope to see this pair, don’t. Their distance is just a bit deceiving.
WISE J104915.57-531906 was first discovered as a single star on a map of the entire sky compiled by NASA’s Wide-field Infrared Survey Explorer (the source of the WISE prefix) by Kevin Luhman, an associate professor of astronomy and astrophysics at Penn State University, due to its rapid proper motion (an animation of its motion can be seen here). It was only when the Gemini South telescope in Chile was aimed at the star in order to obtain a spectrum of it that it was discovered to be two stars, not one.
The best current source of information on this pair is the Penn State Science press release, which is at the link above that contains the animation of the proper motion.
And, since WISE J104915.57-531906 isn’t a back yard telescope object, here’s a peek from the above press release:
Filed under: 3. Double delights |