Hubble Hidden Treasure – Supernova in NGC 5806.
One thing all astronomy enthusiasts can agree upon is the beauty of the Hubble Space Telescope images. In this photograph, galaxy NGC 5806 was chosen by Andre van der Hoeven.
It was to be the subject matter of the Hubble’s Hidden Treasures Image Processing Competition – a project where those who love astronomy search Hubble archives for incredible portraits which haven’t been previously viewed by the public. This new image features NGC 5806 – a rather unremarkable spiral galaxy located about 80 million light years away in the constellation of Virgo. It’s not the biggest, it’s not the brightest, it’s not much special except for one feature… a supernova explosion called SN 2004dg.
In early 2005, a series of exposures were taken to help locate and catalog this supernova which occurred in 2004. While it might have been a year between the explosion and the exposure, the afterglow of the cataclysm still glowed as a faint, yellow dot near the lower half of the galactic image.
Even if it wasn’t considered “special”, NGC 5806 was prime candidate for further supernova study because Hubble had previously taken a series of high resolution images beforehand. This image is produced from three exposures in visible and infrared light, observed by Hubble’s Advanced Camera for Surveys. The field of view is approximately 3.3 by 1.7 arcminutes. Even if galactic images of this type are common, supernovae events aren’t. These “before and after” images are a valuable resource for astronomers who study these violent events.
While looking at the supernova, be sure to take in the galactic structure. The nucleus of NGC 5806 is known as a disk-type bulge, where the spiral formation extends to the center instead of being part of a large elliptical bulge of stars. This beauty is also home to an AGN (active galactic nucleus) – the home of a supermassive black hole sucking in huge amounts of matter from the area around it. As it swirls around the black hole, the matter heats up and emits strong radiation which lights up this image.
Many thanks go to Andre van der Hoeven for getting us to “take a second look”….
Original Story Source: Hubble Space Telescope Image Release.