Interstellar Comet 2I Borisov
Explanation:
From
somewhere else
in the Milky Way galaxy,
Comet 2I/Borisov
was just visiting the Solar System.
Discovered by amateur astronomer Gennady Borisov
on August 30, 2019, the first known interstellar comet
is seen in these two
Hubble
Space Telescope images
from November and December 2019.
On the left, a distant background galaxy near the line-of-sight to
Borisov is blurred as
Hubble
tracked the speeding comet and dust tail about
327 million kilometers from Earth.
At right, 2I/Borisov appears shortly after perihelion, its closest
approach to Sun.
European Southern Observatory
observations indicate
that this comet may never have passed close
to any star before its 2019 perihelion passage.
Borisov's closest
approach to our fair planet, a distance of about 290 million
kilometers, came on December 28, 2019.
Even though Hubble's sharp images don't resolve the comet's nucleus,
they did lead to estimates of less than 1 kilometer for its diameter.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
