[Music throughout] [Hubble Space Telescope images]
2I/Borisov is the first active interstellar comet scientists have seen.
As the comet approached the Sun, it shed millions of gallons of water. [Swift images]
NASA’s Neil Gehrels Swift Observatory measured how much.
Swift made several observations during the comet’s first and only trip through the solar system.
[Illustration] [Approximately 0.5 miles across, 0.74km]
It detected the signal of both water and dust given off by the small comet.
As Borisov neared the Sun, its water production rose similarly to solar system comets.
When it was closest to the Sun, the comet lost enough water to fill a bathtub in about 10 seconds.
At that point, at least 55% of the surface was releasing water, which is about 10 times more than solar system comets.
[Graph of water loss]
As Borisov moved away from the Sun, its water production rate fell off faster than any other comet yet observed.
During its trip, Borisov lost a total of around 60 million gallons of water.
Swift measurements show that material coming off of Borisov is similar to solar system comets.
Thanks to Swift, astronomers have measured the water production of a comet from a planetary system beyond our own.
[Explore: Solar system and beyond]
[NASA]