Five years ago, a fireball hurtled through the cosmos and slammed into Earth, disintegrating in the atmosphere the way space rocks do.
Unbeknownst to anyone, this isn't a regular meteor. This particular meteor's origins, new research reveals, may have been beyond the solar system.
It's the first recorded instance of an interstellar space rock making contact with Earth and only the second interstellar visitor to have been discovered. Back in 2017, an elongated space rock dubbed as the 'Oumuamua
zipped through the solar system at great speed.
Meteor That Hit Earth May Have Come From A Different Star System
In a new paper submitted
to the Astrophysical Journal Letters
, researchers analyzed more than 30 years of data on meteor events recorded by the Center for Near-Earth Object Studies, in hopes of spotting other meteors that may have originated from another star system. The team focused specifically on the fastest meteors on record, since rocks traveling at great speed is less likely to be gravitationally bound to the sun and originate outside the solar system.
With this method, they identified one: a 3-foot meteor at an altitude of 11.6 miles above Papua New Guinea and a speed of 134,200 miles per hour. Its trajectory is consistent with origins from outside the solar system.
"We can use the atmosphere of the Earth as the detector for these meteors, which are too small to otherwise see," Avi Loeb, chair of astronomy at Harvard University, explains
Loeb and study lead author Amir Siraj, a student at Harvard University, found two other meteors at the same speed of the 2014 meteor. However, one proved to be gravitationally bound to the sun, while they were unclear about the origins of the second one.
Alien Material Within Interstellar Rocks
Finding objects with origins in distant stars
is a great step in understanding the world beyond the solar system.
In January 2019, Loeb suggested that 'Oumuamua could be an alien probe
or some other type of extraterrestrial technology.
While Loeb did not make a similar suggestion about the 2014 meteor, the authors did point out in the paper that it's possible for interstellar space rocks to have originated from a habitable region in another star system. If so, interstellar meteors that make their way to Earth may carry inside it tiny life forms or seeds, according
to a report from CNET.
"You can imagine that if these meteors were ejected from the habitable zone of a star, they could help transfer life from one planetary system to another," Loeb says to Space.com.