Explanation:
NGC
4631 is a big beautiful spiral galaxy
seen edge-on (top right)
only 25 million light-years away towards the small northern
constellation
Canes
Venatici.
This galaxy's slightly distorted wedge shape suggests to
some a cosmic herring and to others the popular moniker of
The Whale Galaxy.
Either way, it is similar in size to our
own Milky
Way.
In this gorgeous color image,
the Whale's dark interstellar dust clouds, yellowish core, and young
blue star clusters are easy to spot.
A companion galaxy, the small elliptical NGC 4627, appears above the
Whale Galaxy.
At the lower left is another distorted galaxy,
the hockey stick-shaped
NGC
4656.
The distortions and mingling
trails of gas detected at other
wavelengths suggest that all three galaxies have had
close
encounters with each other in their past.
The Whale Galaxy is also known to have spouted a halo of hot gas glowing
in x-rays.
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