The comet known as C/2017 U1 was discovered on September 24 by the Pan-STARRS 1 telescope in Hawaii when it was making its way away from the sun after a close approach with our host star.
Astronomers noted that, while most comets burn up when they get close to a star, this one remained relatively dim as it was travelling way too fast – at 16 miles per second – to be burnt up by the sun’s heat.
Now the rock is on its way outwards, it is unlikely to return to our neck of the cosmos ever again.
Observations published by the International Astronomical Union’s Minor Planet Center (MPC) believe the comet likely escaped the orbit of another star.
The MPC said: “If further observations confirm the unusual nature of this orbit, this object may be the first clear case of an interstellar comet.”
It appears to have come from the star Vega – some 25 light years away – although this is likely to be where it first formed.
Astronomer Bill Gray said: “Once one of these objects gets kicked loose, it’ll roam the Milky Way for billions of years.
“Massive amounts of material were ejected from the solar system when it was formed; much of it is probably still wandering around, having gone around the galaxy over a hundred times. “Other stars, we may assume have similarly scattered bits all over the place.”
Gareth Williams, associate director of the MPC added: “Further observations of this object are very much desired.
“Unless there are serious problems with much of the astrometry listed below, strongly hyperbolic orbits are the only viable solutions. “If further observations confirm the unusual nature of this orbit, this object may be the first clear case of an interstellar comet.”