In 1572 a star exploded and people saw it with the naked eye. One of them was Danish astronomer Tycho Brahe, for whom the supernova was eventually named.
About 400 years ago Tycho showed this “new star” was far beyond the Moon. But astronomers now know that Tycho’s new star (also known as SN 1572 or B Cassiopeiae) wasn’t new at all. Rather it marked the death of a star in a supernova.
This object continues to puzzle astronomers to this day. That’s because SN 1572 doesn’t look like other supernovae – it’s all clumpy and lumpy. But astronomers are using simulations to figure out how it got that way.
The supernova in question is a Type Ia. These supernovae occur when a white dwarf star sucks so much matter from its companion star until a violent explosion happens. This completely destroys the white dwarf blowing its debris outward into space.
You Might Like This: “Observing Supernova 1987A“
Just like many other supernova remnants, the Tycho supernova glows brightly in X-ray light because shock waves generated by the stellar explosion heat the stellar debris up to millions of degrees.
NASA’s Chandra X-ray Observatory reveals that, although the supernova remnant looks spherical, its actual surface is wildly bumpy.
To emphasize the clumps in the image and the three-dimensional nature of Tycho, scientists selected two narrow ranges of X-ray energies. Blue color shows silicon moving away from Earth, while red shows silicon moving towards us.
Other colors in the image show different elements moving in a variety of directions at different velocities.
A series of simulations conducted by astronomers suggested there are two options for these crazy dynamics: one of the simulations started with clumpy debris from the explosion. The other began with smooth debris from the explosion and then the clumpiness appeared afterward as the supernova remnant evolved and tiny irregularities were magnified.
Scientists then compared results from the Chandra and the simulations. They found that the clumpiness was most likely produced during the supernova explosion.
Astronomers still don’t know how it happened but they suggest that the explosion ignited at many spots around the star, instead of just one.
A paper describing the results appeared in the June 1st, 2019 issue of The Astrophysical Journal and is available online.