In the first direct observation of the sexiest of interstellar shenanigans, a binary star system has been caught in the act of merging.
Scientists have long since speculated that closely orbiting binary stars or multiple star systems, which whirl so close to one another that their outer layers actually touch, would eventually combine.
And now we’ve caught those dirty plasma balls in the act.
And in the grandest scientific tradition… we did it by chance. The binary pair in question, V1309 Scorpii, was discovered in 2008 when it erupted in a bright flare. However, scientists hadn’t been able to figure out why.
Enter Romuald Tylenda of the Nicolaus Copernicus Astronomical Center in Toruń, Poland.
Now, the Optical Gravitational Lensing Experiment (OGLE… great acronym for a telescope or greatest acronym?) at Warsaw University Observatory is a project that’s been hunting for dark matter for fifteen or so years. Tylenda, apparently ignoring OGLE’s actual task, recently realized that OGLE was pointed in V1309 Scorpii’s direction for years, so he dug through more than 2,000 observations taken from 2002 to 2010 and found light variations that suggest V1309 Scorpii was originally a contact binary star with an orbital period of about 1.4 days. That period decreased over time, and the outer layers of both stars combined into a single enveloping cocoon. The fusing object than continued to get brighter and brighter, its light doubling every 19 days until fall of 2008, when it brightened by a factor of 300 over 10 days. Following this, the cores of the stars merged, causing energy to erupt outward and the star to become 10,000 times brighter than its original luminosity. After this explosive act, the new star quickly faded back to it’s original brightness.
I like to think of that period as the afterglow.
Anyway… that’s the scenario Tylenda believes the data points to, but we are currently unable to verify it. To do so, we’d need to directly observe the final shape of the object, which would be a star with a fast spin and a strange internal structure. Unfortunately, the detritus thrown off during coalescence currently blocks V1309 Scorpii, so despite scientists requesting time with the Hubble Telescope to observe the object, it could be years before the material dissipates enough for us to view the object.
Good job, space. You’ve foiled our plans again.