A 2-year time lapse series of the ticking time bomb V445 Puppis. Click for larger. Image credit: ESO

Here is a great example of the process leading up to a type 1A supernova. Most of the time when we think of a supernova we think of a massive star collapsing in on itself because it has exhausted all of its fuel and gravity overcomes the force of the nuclear fires and hydrostatic pressure is lost and there is a collapse of titanic proportions. However there is more than one way to create a supernova and V445 Puppis is a great example of what could become such a supernova called a Type 1A supernova.

Here’s the short version from the ESO:

Using the NACO adaptive optics instrument on ESO’s Very Large Telescope and its ability to obtain images as sharp as if taken from space, astronomers have made the first time-lapse movie of a bipolar shell ejected by a “vampire star”, which underwent an outburst after gulping down part of its companion’s matter. This enabled them to determine the distance and intrinsic brightness of the object. It appears that this system is a prime candidate to be one of the long-sought progenitors of the exploding stars known as Type Ia supernovae, critical for the study of dark energy. The images of V445 Puppis cover a time span of two years. The images unambiguously show a bipolar shell, initially with a very narrow waist, with lobes on each side. Two knots are also seen at either extreme end of the shell, which appear to move at about 30 million kilometres per hour. The shell — unlike any previously observed for a nova — is itself moving at about 24 million kilometres per hour. A thick disc of dust, which must have been produced during the last outburst, obscures the central couple of stars.