A supernova and its host galaxy are the subject of today’s NASA/ESA Hubble Space Telescope Picture of the Week. The galaxy in question is LEDA 132905, which is situated in the constellation Sculptor. Even at over 400 million light-years away, LEDA 132905’s spiral structure is faintly visible, as are patches of bright blue stars.
The bright white dot directly in the centre of the image, between the bright centre of the galaxy and its faint left edge, is a supernova named SN 2022abvt. SN 2022abvt was discovered in late 2022, and Hubble
observed the explosion about two months later. This image was
constructed from data collected to study Type Ia supernovae, which occur
when the exposed core of a dead star ignites in a sudden, destructive
burst of nuclear fusion. Researchers are interested in this type of
supernova because they can be used to measure precise distances to other
galaxies.
The Universe is a big place, and supernova explosions are fleeting.
How is it possible to be in the right place at the right time to catch a
supernova when it happens? Today, most supernovae are discovered by
robotic telescopes that continuously scan the night sky. But some are
still found the old-fashioned way, by careful observers who take
repeated images of the sky and search for changes. SN 2022abvt was
spotted by the Asteroid Terrestrial-impact Last Alert System, or ATLAS.
As the name suggests, ATLAS was designed to track down the faint,
fast-moving signals from asteroids
close to Earth. In addition to searching out asteroids, ATLAS also
keeps tabs on objects that brighten or fade suddenly, like supernovae,
variable stars and galactic centres powered by hungry black holes.