On the image captured by NASA and ESA’s Hubble Space Telescope، the asteroid can be seen with two thin tails of debris trailing it. Evidently، each tail is representative of an event wherein the asteroid is shedding off material، suggesting that it is beginning to come apart.
The debris tail was first observed in January of this year by the University of HawaiiNASA ATLAS. Shortly after، the second debris tail was observed by multiple telescopes. According to experts، the events that resulted in the tails likely occurred around Oct. 28 and Dec. 30، 2018.
That said، the tails will only be visible for a few months and eventually disappear.
YORP Torque Gault was discovered in 1988، but these images provide the first evidence that it is on the slow path to self-destruction. That said، it is not the only asteroid known to be disintegrating through the process called YORP torque.
In this process، when the sun heats the surface of an asteroid، the heat and momentum result in a force that caused the asteroid to spin even faster. This eventually renders the asteroid unstable، and the landslides on the asteroid release the rubble into space، thereby leaving the long tails on its trail.
According to astronomers، in the over 800،000 known asteroids in the asteroid belt between Jupiter and Mars، such YORP Torques occur about once a year.
“This self-destruction event is rare. Active and unstable asteroids such as Gault are only now being detected by means of new survey telescopes that scan the entire sky، which means asteroids such as Gault that are misbehaving cannot escape detection any more،” said Olivier Hainaut of the European Southern Observatory.