A supernova is a massive explosion of energy that occurs when a star runs out of fuel. These events can be so bright that they outshine entire galaxies, but they don’t last for long — just the blink of an eye, in cosmic terms. It’s hard to capture the sudden brightness and fast dimming of a supernova event, because they are difficult to predict, but the Hubble Space Telescope recently managed to capture three different moments of a supernova in a single image.
“It is quite rare that a supernova can be detected at a very early stage, because that stage is really short,” said Wenlei Chen, an author of the paper, in a statement. “It only lasts for hours to a few days, and it can be easily missed even for a nearby detection. In the same exposure, we are able to see a sequence of the images—like multiple faces of a supernova.”
A phenomenon called “Seeing Three” allowed you to see three different points at the same time. gravitational lensingIn which a large object is placed between us and the object being viewed. If the intermediate object is large enough, gravity can cause space to be warped, changing the view of what is behind it. This background object can appear brighter than the intermediate object, which acts as a magnifying mirror and can appear at a different location in space when its light is bent. In this instance, the light from a supernova was bent along three different paths. Hubble therefore received three distinct instances.
The supernova is an extremely distant one, meaning it is ancient — it is estimated that it occurred 11 billion years ago, which is close to the start of the universe 13.8 billion years ago. This is one of the earliest supernovae observed in such detail, and because of the three different time points captured in the image, researchers were able to measure the star’s size. The star is approximately 500 times larger than the sun, which is a type of star known as a red supergiant.
The journal publishes the research. Nature.