A supernova has been discovered In the Pinwheel Galaxy (M101) by a team involving Oxford researchers. Found on 24 August, it is the nearest type 1A supernova found since 1972. For a short time it will be bright enough to be seen through a pair of binoculars or small telescope.
The supernova was discovered by an automated robotic search. Certain galaxies are scanned by a powerful telescope each night, and the current appearance of each galaxy is compared to a previously recorded image of that galaxy. Any differences are detected, and then investigated further.
Robert Massey of the Royal Astronomical Society explained the significance of Type IA supernovas, telling Cherwell that these phenomena are formed when “you get a binary system where one star dumps mass onto a dense stellar companion white dwarf star. And when that’s very overloaded with material you get a dramatic explosion… that completely destroys the white dwarf”. This explosion happens when the white dwarf star reaches a certain mass. As a result all type 1A supernovas explode with the same brightness.
This allows researchers to discover how far away galaxies are, and has meant type 1A supernovas have played a vital role in astrophysics. In particular they have helped to estimate the rate at which the universe is expanding, and the amount of “dark energy” in the universe.
Massey explained why the discovery is beneficial to further research, saying, “It’s good to see one that’s close because then you can understand more about the characteristics of this type. By looking at the way the light rises, brightens and fades, you get an insight into the processes.”
For a short time, amateur astronomers should be able to view it, although Massey warns “it’s likely to be quite difficult”, and that “there has been a certain amount of sensationalism about how bright it is”.
