Here is a really "hot" (both metaphorically speaking, and in actual physical measurements....) image of M66 and M65 in the Far ultraviolet and Near ultraviolet.
(GALEX satellite observation)
The spiral arms of these galaxies, which are so difficult to characterize from observations at visible wavelengths, are here plainly outlined in blue and white, which traces far-ultraviolet light coming from young and luminous stars.
This is a most instructive image, in terms of deciphering the morphology of these two galaxies.
For instance there is some very odd detail in the shorter and broader of the two spiral arms of M66!
cheers, madbadgalaxyman
P.S.
Mr V.Bad Galaxy Man has had an ongoing argument (with himself!!!) regarding whether or not M66 is meaningfully perturbed by one or more nearby galaxies.....I think the GALEX image supports the case that there is at least a mild perturbation.
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Bad Galaxy Man's question of the day:
Is there anything at all that is unusual about M65 ???
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Added, in later edit.
A larger FUV+NUV image of M66, downloaded from GalexView:
The brightest FUV knot may be a star cloud, or it may be something more unusual; it is unusual to find a really bright FUV and blue feature at this position in a non-dwarf barred spiral galaxy.
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