University’s high-speed camera captures rare ‘black widow’ stars

ASTRONOMERS HAVE discovered an extremely rare ‘black widow’ binary star using a superhigh-speed camera developed by researchers at the University of Sheffield.

Black widow binaries are a pairing of two stars, where one neutron star spins in circles to slowly consume its smaller companion, as its arachnid namesake might do to its mate.

Now an international team of astronomers led by MIT have discovered a new one using Sheffield’s HiPERCAM, which can take more than 1,000 optical images per second.

And what makes it a rare triple black widow is that it also appears to host a third far-flung star that orbits around the two inner stars every 10,000 years.

The findings, published in Nature, outline a new way to discover such black widows by identifying their companion stars instead of looking directly for the main pulsars.

Using Sheffield’s HiPERCAM, the research team was able to use this second star’s varying light to discover what they have named ZTF J1406+1222. The new method could make it easier to discover black widows in the future.

Professor Vik Dhillon, co-author of the study from the University of Sheffield’s Department of Physics and Astronomy, said: “Thanks to the extraordinary sensitivity of the Sheffield-led HiPERCAM camera, we have discovered the most extreme member of the black widow class of binary star, along with a promising new method of detecting such systems.”

Around two dozen black widows have been identified in the

Milky Way, but this new one has the shortest orbital time yet – with the two stars circling each other every 62 minutes.

The discovery has also raised questions about how it could have formed, with researchers speculating it likely came from a dense constellation of old stars known as a globular cluster.