Hubble captures rare image of an active asteroid disintegrating

The Hubble Space Telescope has captured a rare image of an active asteroid that is in the process of self-destructing, the ESA and NASA have jointly announced. The image features asteroid (6478) Gault, which was discovered in 1988 and is estimated to have a width of at least 2.5 miles / 4km. Visible in the image are two debris tails, which experts say are signs that the asteroid is disintegrating.READ: NASA DART mission will slam spacecraft into an asteroid

The space rock featured in the Hubble image, 6478 Gault, is known as a Phocaea asteroid because it originates from the inner region of the Asteroid Belt. The asteroid was discovered around three decades ago; there is some contention about how large it is, with NASA pinpointing 2.5-miles and the ESA estimating up to 9km / 5.6 miles.

Hubble's image has a very obvious, striking feature: two seemingly glowing tails streaking away from the asteroid. These tails, according to NASA, are the result of debris thrown from the body due to its rapid spin. This loss of material is a sign that 6478 Gault is slowly disintegrating.

This asteroid joins only a handful of others caught in the act of breaking apart, making this an exceeding rare space image. The process of disintegration is due to something called YORP torque, which is a rapid spin caused by the asteroid warming up from solar radiation. Assuming the spin is fast enough to overcome gravity, the asteroid is considered unstable as it begins ejecting material into space.

According to ESA, though there are 800,000 known asteroids in the Asteroid Belt, scientists estimate a YORP disruption only happens around once every year. That rarity accounts for the relative lack of images showing the event; as such, the image of Gault is a special opportunity for researchers to study the phenomenon and asteroid.