I believe Arp 25 might be one of the few examples of Jellyfish galaxies where we can visually see the effects of ram pressure stripping from the galaxy falling through the intracluster medium in sm. I base this on the following snippet from this paper:
"Rasmussen et al. (2006) and Wolter et al. (2015) conclude that ram pressure (along with viscous effects) is responsible for both the disturbed morphology and high star formation rate (SFR) in NGC 2276"
The paper by Rasmussen et. al. referenced argues that ram-pressure stripping is the more likely explanation for the bow shock of star forming knots seen on the western front of the galaxy:
"The distributions of optical light, H-i gas, and radio continuum emission in this galaxy show a bow-shock-like structure along the western edge, which may suggest a shocked gas component. If so, the galaxy must be moving supersonically through the ambient IGM. Evidence supporting this interpretation is the high star formation rate (SFR) of NGC 2276 (?5-M?-yr?1; Davis et al. 1997), with much of this starburst activity occurring along the western edge, as expected if an interaction with the IGM has triggered some of the star formation via ram-pressure compression of molecular gas."
What I am not sure of, is whether the asymmetric position of the visual nucleus is also a result of ram pressure stripping. In any case, it looks like some of the star formation on the bow shock was picked up by Howard in his 28" sketch.
Motivated by its Jellyfish nature, I looked at Arp 25 during the January new moon:
"NGC 2276 appeared as a very low surface brightness circular glow. A bright star nearby detracts from the view. The asymmetry of the glow (presumably attributed by the paper to ram-pressure stripping) was challenging, but certainly detected to be lopsided in the direction of the star."
and also NGC 2300:
"NGC 2300 nearby appeared as an easy, high surface brightness elliptical glow. The two made for a nice pair in the same FOV."
Clear Skies!
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