Could comet 2I/Borisov, currently coursing through our solar system, hold cosmic secrets?
- First spotted on August 30, from a Crimean mountain village, the comet has been travelling for millions, if not billions, of years
- For astronomers, it is a care package from the cosmos – a key to worlds they cannot directly observe
Something strange is sailing towards us. Something small and cold and extraordinarily fast. No one knows where it came from, or where it is going. But it’s not from around here.
This is an interstellar comet – an ancient ball of ice and gas and dust, formed on the frozen outskirts of a distant star, which some lucky quirk of gravity has tossed into our path.
To astronomers, the comet is a care package from the cosmos – a piece of a place they will never be able to visit, a key to all the worlds they cannot directly observe.
It is only the second interstellar interloper scientists have seen in our solar system. And it’s the first one they’ve been able to get a good look at. By tracking the comet’s movement, measuring its composition and monitoring its behaviour, researchers are seeking clues about the place it came from and the space it crossed to get here. They have already found a carbon-based molecule and possibly water – two familiar chemicals in such an alien object.
Wow. I was not expecting to see anything like that
As the sun sinks behind the mountains in the American state of Tennessee, and stars wink into view, astronomer Doug Durig climbs onto the rooftop of his observatory, powers up his three telescopes and angles them skyward.
Every night, the comet grows bigger and brighter, expelling streams of gas and dust that may offer up clues to its history. On December 8, it was due to make its nearest approach to Earth, offering researchers an up-close glimpse before zooming back into the freezing, featureless void.
