A rare kind of space object, which is something between an asteroid and a comet, has been discovered by astronomers. It has been called an active asteroid.
The newly discovered asteroid named 2019 LD2 has an orbit like an asteroid but the tail of a comet. While not entirely unknown, what makes 2019 LD2 special is that it shares Jupiter’s orbit in an asteroid swarm known as the Jupiter Trojans.
This is the first Jupiter Trojan astronomers have ever seen spewing out gas as a comet would.
The celestial body first grabbed the attention of astronomers last year in June when University of Hawaii’s Asteroid Terrestrial-impact Last Alert System (ATLAS) detected a faint new signal that appeared to be an asteroid in the Trojan group.
Subsequent observations confirmed the comet-like properties and in April 2002, researchers found that it still had a tail.
There are two theories as to why LD2 is active and among the Jupiter Trojans.
According to a report in Science Alert, astronomer Alan Fitzsimmons of Queen’s University Belfast, Ireland, said that they have believed for decades that Trojan asteroids should have large amounts of ice beneath their surfaces, but there was never any evidence till now.
“ATLAS has shown that the predictions of their icy nature may well be correct,” Fitzsimmons added.
The report said that it is possible that the LD2 collided with another asteroid and exposed the previously sealed ice leading to the tail and gas leak.
The second theory is that LD2 was a stray asteroid 2 captured by Jupiter from further out in the solar system where it is cold enough for ice to remain on the surface.
In December 2019, a group of astronomers had put in a request to take a closer look at the heavenly body using the Spitzer Space Telescope. However, Spitzer was retired in January of this year.