However you pronounce its name, the star Betelgeuse is hard to miss on a clear winter’s night. Representing the top left shoulder of Orion the Hunter it blazes a bright red colour. At over 600 light years away Betelgeuse is not particularly close, but it shines 100,000 times as brightly as our Sun.
Betelgeuse is a “red supergiant” star which is nearing the end of its life. As it has swelled in size over the past few hundred thousand years, currently measuring around 1000 times the size of our Sun, the massive star has been shedding its outer layers. This material is made of gas and dust, which has cooled over time and is seen here in far-infrared light by Herschel.
The ejected outer layers of the star expanded outwards until they hit the surrounding material, creating the arc-like structures seen to the left of the image. These arcs are a bow shock, similar to the wave that travels in front of a ship moving through water, and are caused by Betelgeuse’s motion through the surrounding gas cloud at around 30 km/s (70,000 mph).
Further to the left is what appears to be a straight wall of gas and dust, the origin of which is uncertain. It is very hard to measure distances in images such as this, so the wall could be much futher away or closer to Earth than Betelgeuse - essentially in the foreground or background.