If you thought every object out in the deep dark vastness of space was already discovered, you thought wrong.
Almost every day, astronomers spot something they haven't seen before, and only a few days ago, researchers from the University of Hawaii used the Asteroid Terrestrial-impact Last Alert System or ATLAS and found a Trojan asteroid called 2019 LD2. This asteroid was found to have a strange orbit, and also very active. On top of that it has an icy tail, and according to astronomers appears to be a unique "crossover" between an asteroid and a comet.
Trojans are usually found to be billions of years old, and most of the time, the ice has been melted due to exposure from the sun and they are no longer active. Astronomers also detailed that the newly found Jupiter Trojan has only been active for less than a year, suggesting that Jupiter may have captured the asteroid from a distant colder orbit. Another theory is that the asteroid was hit by another space rock that caused its once safe ice to be exposed. If you want to read more, check out the press release from the University of Hawaii here.