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In a strange twist of fate…

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…NASA’s Hubble Space Telescope accidentally
witnessed a comet in the act of breaking apart.

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Astronomers did not know that Comet K1
was breaking apart when they first viewed it…

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…In fact, this comet wasn’t even Hubble’s original target.

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The team chose Comet K1 when they
were unable to observe their first choice.

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To the surprise of researchers,
Hubble returned images with at least four comets.

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Each fragment had a distinct coma,
the fuzzy envelope of gas and dust
that surrounds a comet's icy nucleus.

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Hubble cleanly imaged the fragments…

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…but from ground-based telescopes,
they appeared as bright blobs.

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Hubble’s images were taken just one month after
K1’s closest approach to the Sun, called perihelion.

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During perihelion, a comet experiences
its most intense heating and maximum stress.

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Just past perihelion is when some
long-period comets like K1 tend to fall apart.

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Some of Hubble’s most famous images of
a fragmenting comet are of Comet Shoemaker-Levy 9…

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…but those Hubble images were taken
long after the comet broke into pieces.

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The team estimates that K1 began
to disintegrate eight days before Hubble viewed it.

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Hubble took three images, one on each day
from November 8 through November 10, 2025.

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As it watched the comet,
one of K1’s smaller pieces also broke up.

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Because Hubble’s sharp vision can distinguish
extremely fine details, the team could trace the history
of the fragments back to when they were one piece.

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That allowed them to reconstruct the timeline.
But in doing so, they uncovered a mystery:

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Why was there a delay between
when the comet broke up and when
bright outbursts were seen from the ground?

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When the comet fragmented
and exposed fresh ice,
why didn’t it brighten almost instantaneously?

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The team looks forward to finishing
their analysis of the gases released by the comet.

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Spectroscopic analysis from Hubble’s instruments
will likely reveal much more about the composition
of K1 and the very origins of our solar system.

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Hubble's data could provide key insights into
the physical processes active on the comet's surface.

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K1 is now a collection of fragments
about 250 million miles from Earth.

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It is heading out of the solar system,
not likely to ever return.

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Never before has Hubble caught a fragmenting
comet this close to when it actually fell apart.

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Sometimes the best science happens by accident.

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[ Follow us on social media @NASAHubble ]

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[ NASA MEATBALL!!!!!! ]