Has another interstellar visitor been found?
An amateur astronomer has discovered a comet that could come from outside our Solar System. If so, it would be the second interstellar object after the elongated body known as 'Oumuamua was identified in 2017.
The Minor Planet Center (MPC) at Harvard University has issued a formal announcement of the discovery. The body appears to have a "hyperbolic" orbit, which would appear to indicate its origin in another planetary system.
A hyperbolic orbit is an eccentric one, where the shape deviates substantially from that of a perfect circle. A perfect circle has an eccentricity of 0. The elliptical orbits of many planets, asteroids and comets have eccentricities between 0 and 1.
The newly discovered object - initially given the designation gb00234, but now known as Comet C/2019 Q4 (Borisov) - has an eccentricity of 3.2, based on current observations.
It was noticed by the amateur stargazer Gennady Borisov on 30 August at the Crimean Astrophysical Observatory in Bakhchysarai. At the time, it was about three astronomical units (about 450 million km) from the Sun. -BBC