An amateur astronomer may have detected an object from outside our solar system, according to an announcement from the Minor Planet Center.
Astronomers saw the first known interstellar object, called ‘Oumuamua, in 2017. Its hyperbolic orbit indicated it had arrived from afar and wouldn’t be coming back. Tons of speculation followed as to what the object might be, speculation that of course included aliens. The newly spotted object would be the second such interstellar visitor—but there’s a lot more observing yet to come.
An amateur astronomer named Gennady Borisov first spotted the object on August 30, using a telescope he built himself. Other observations (and hype) have followed. Today, the Minor Planet Center at the Center for Astrophysics released an official circular on the object, now provisionally called C/2019 Q4 (Borisov). If scientists confirm its interstellar nature, it will receive a new name that begins with 2I, denoting it as the second interstellar object.
With more observations of the object, scientists have begun calculating the shape of its orbit. These calculations seem to reveal that the trajectory has a hyperbolic shape—rather than the elliptical shape that characterizes the orbits of things circling the Sun. The trajectory suggests that the object will eventually exit the solar system, never to return.
Astronomer Michele Bannister at the Astrophysics Research Centre at Queen’s University tweeted that other objects have at first been found to have hyperbolic orbits, only to be resolved to more typical orbits once more observations came in.
“Further observations are clearly very desirable,” reads the MPC circular.
Matthew Holman, the MPC’s director, told Gizmodo that the object is near the Sun in the sky when viewed from Earth, making it challenging to observe, and astronomers must be careful about potential effects the atmosphere might have on any observations.
Interstellar objects are exciting, since they presumably carry information on what stuff looks like elsewhere in the galaxy. The first interstellar visitor, ‘Oumuamua, brought lots of excitement; to some, its strange, cigar-like shape seemed almost impossible. This new object will certainly bring its own hype and speculation (and, surely, more talk of aliens). But it’s especially exciting because astronomers will be able to make comparisons between it and ‘Oumuamua. Initial observations already reveal that the object is an active comet with a big temporary atmosphere, or coma, Holman said.
“Absent an unexpected fading or disintegration, this object should be observable for at least a year,” according to the circular. We look forward to learning more about this potential visitor in the coming months.