Photo courtesy of NASA
by Dillan-James Carter
On the 30th of August, amateur astronomer Gennady Borisov spotted what could be the second interstellar object to enter our solar system since Oumuamua (pronounced ‘Oh mooer mooer’), the cigar-shaped comet identified in 2017.
The Micro Planet Centre (MPC) at Harvard University issued a formal announcement of the discovery of this interstellar object on the 11th of September. What has given us an early indication of the interstellar claim is the evidence of the ‘hyperbolic’ orbit; this one being an erratic one, unlike the usual circular to elliptical orbits which we would expect from an object in this solar system. Normally, a perfect circle would have an eccentricity of 0, and a highly elliptical orbit would have one of 1, but current observations of Comet C/2019 Q4 (Borisov), it is shown that there is an eccentricity of 3.2, which makes it clearly out of our ballpark.
Oumuamua, the first interstellar comet, was discovered on the 19th of October 2017, though unfortunately, it was found too late to be of any major benefit to astronomers as it was leaving our solar system at the time. Borisov, however, is still approaching our planetary system and won’t reach its closest orbit to the sun until the 10th of December--this, as well as its 20km width and brightness, make it lend itself greatly to further study of its various properties. Keep an eye on the sky in the months to come, as astronomers will receive further details on our second interstellar visitor.