NASA has discovered the oldest, furthest supernova known to exist, using the Hubble Space Telescope, and providing additional clues to understanding the evolution of the universe.
The exploding star, called Supernova UDS10Wil or SN Wilson, is a Type Ia supernova that burst over 10 billion years ago. Type Ia supernovas are used to measure the expansion of the universe and also provide clues into dark energy, the unknown force thought to be behind the universe's expansion.
"This new distance record holder opens a window into the early universe, offering important new insights into how these stars explode," Johns Hopkins University astronomer David Jones said. "We can test theories about how reliable these detonations are for understanding the evolution of the universe and its expansion."
In order to find the supernova, NASA used Hubble to study far away Type Ia supernovae over the course of three years. They used Hubble's Wide Field Camera 3 to find the supernovae and determine their distance through spectroscopy.
What exactly causes a supernova remains unknown. One theory involves a white dwarf drawing matter from a nearby red giant. The other consists of the merging of two white dwarfs.
The new supernova SN Wilson points toward the latter theory. The drop-off of Type Ia supernovae from 7.5 to 10 billion years ago presents an idea of how long it takes two white dwarfs to merge.
"This new result is a really exciting step forward in our study of supernovae and the distant universe," team member Jens Hjorth of the Dark Cosmology Centre at the University of Copenhagen said. "We can begin to explore and understand the stars that cause these violent explosions."
"If supernovae were popcorn, the question is how long before they start popping?" Adam Reiss of Space Telescope Science Institute asked. "You may have different theories about what is going on in the kernel. If you see when the first kernels popped and how often they popped, it tells you something important about the process of popping corn."
The results of the discovery will be published in a forthcoming issue of The Astrophysical Journal.
