One of the most frustrating things about astronomy is that most of the things we’re interested in don’t change on human timescales or even humanity-length time scales. Planets form over hundreds of thousands of years, galaxies merge over billions of years. Things generally don’t change such that we can see them. There are explosive exceptions, however. Supernovae can go off in moments, and generate nebulae that we can see expanding across years.

Recently, a team of astronomers using the Hubble Space Telescope imaged a ghostly nebula in the nearby Small Magellanic Cloud. This is a supernova remnant with the uninspired name 1E 0102.2-7219. This object was imaged twice by Hubble, with the two data sets being taken ten years apart. Careful analysis of the tadpole-shaped knots of glowing gas revealed their slow motion across the sky. Working backward, researchers John Banovetz and Danny Milisavljevic were able to estimate this supernova’s initial explosion could have been roughly 1700 years ago, during the Roman Empire, had the Roman Empire been in the Southern Hemisphere. Unfortunately, this object’s southern location means it was probably seen but by a culture that hasn’t left us written records we can look through.

Supernovae like this should produce a neutron star when they go off, and this neutron star can be sent rocketing out of the explosion like a cannonball. This team used their Hubble data to try and find where that neutron star ended up. They’re not sure if they’ve found it or found a knot of glowing gas masquerading as a neutron star. If they did find it, the neutron star would have been the fastest so far detected and would have been moving at an amazing two million miles per hour. More observations are needed, and when they are published, we’ll bring you an update right here on the Daily Space.

More Information

NASA Goddard press release