This unusual object is an asteroid called 6478 Gault. It’s unusual because it has a tail and an asteroid doesn’t usually have a tail.
It’s thought this asteroid collided with something some time around November 2018 as images around then didn’t note a tail. If the tail is a result of a collision and this is confirmed, this could quite possibly be the first such observation.
This image is based on an observation by Slooh.com member MartinD.2017. Martin scheduled the missions and shared his FITS files, so I was able to process the FITS files to produce this image. This asteroid was observed on January 30, 2019 using the Canary Two telescope; there were five missions that made up this observation.
The stars in this image are stretched out because I aligned the image based on the asteroid, which was moving through the field of view during the observations. As a result, the stars appear to be trailed while the asteroid is stationary.
I used MaxIM DL to stack and align this image. If I used AstroImageJ, I could have stacked this such that the asteroid was not stationary, but I wanted to get the most luminance on the asteroid.
Update March 2019 – Hubble has imaged this amazing asteroid! Here’s the link to the article and amazing photo: http://www.sci-news.com/astronomy/hubble-multi-tailed-active-asteroid-07038.html