The Blue Ring Nebula, a star with an unusual ultraviolet ring around it spotted by astronomers working for NASA's now-defunct Galaxy Evolution Explorer mission (GALEX) sixteen years ago has amazed and perplexed researchers since its discovery. Now, it seems astronomers may have finally unearthed the mystery behind it.
It turns out that the ring around the object may actually be the base of a cone-shaped cloud of fluorescing debris created after a sun-like star collided into a smaller stellar companion, engulfing it in the process. As a result, two cones of material were shot out in opposite directions, one of which was pointed directly toward Earth appearing to GALEX as a ring.
A common occurence
"The merging of two stars is fairly common, but they quickly become obscured by lots of dust as the ejecta from them expands and cools in space, which means we can't see what has actually happened," said in a statement lead study author Keri Hoadley, the David and Ellen Lee Postdoctoral Scholar in Physics at Caltech.
"We think this object represents a late stage of these transient events, when the dust finally clears and we have a good view. But we also caught the process before it was too far along; after time, the nebula will dissolve into the interstellar medium, and we would not be able to tell anything happened at all."
To achieve this discovery the team used the help of many telescopes: Caltech's Hale Telescope at Palomar Observatory near San Diego, the W. M. Keck Observatory in Hawaii, the Hobby-Eberly Telescope in Texas, NASA's Spitzer Space Telescope, and the Wide-field Survey Explorer (WISE). With these powerful tools, the team was able to put together the story of the Blue Ring Nebula, much to the relief of the researchers who had been trying to figure it out for years.