A new interstellar object has been discovered passing through the solar system. Discovered by Ukrainian amateur astronomer Gennady Borisov on 30 August, 2019. The veteran comet hunter pointed the pointed the Crimean Astrophysical Observatory low on the northeastern horizon to Gemini perilously close to the Sun’s glare. Now the object has been designated Comet C/2019 Q4 (Borisov). At the time, the comet was approaching the inner solar system from beyond the orbit of Mars.
This is only the second such object to be discovered and tracked entering our solar system from interstellar space. The first being Oumuamua (1I/2017 U1) discovered in October 2017. Recent observations show that this distant visitor has a hyperbolic orbit travelling at a whopping 68,700 mph to never return. It appears to have a coma and a slight tail suggesting this really is a comet.
Comet Borisov Closest Approach
C/2019 Q4 will reach closest approach to the Sun on 07 December, 2019 followed by closest approach to the Earth on 29 December at a safe distance of around 2AU. At the time of writing, the comet is only magnitude +18 making it a difficult target for backyard telescopes. However, it is bigger and brighter than Oumuamua.
No doubt more careful observations will made made as this visitor passes through our neighbourhood. Unlike Oumuamua, astronomers will have plenty of time to try to answer more questions about this intriguing object as it passes in the month’s ahead and on in to next year.
Exciting times for comet hunters and cosmologists alike.