Ok, thanks.To me, NGC 1097A looks far more like a distant unrelated (and undisrupted) background galaxy than an interacting companion of NGC 1097. But all the sources I've found seem to disagree with me.NGC 1097 and NGC 1097A have much the same radial velocities, meaning that they are at much the same distance. They could indeed be entangled inside one another, but they will have their own velocity due to their interactions, which will suggest that they are at somewhat different distances. even though they are not.
The reason why NGC 1097 looks so undisturbed is almost certainly because it hasn't got any "arm fluff". It may very well have had arms before it started interacting with NGC 1097, but it has lost its arms since then. Therefore it looks undisturbed.
Take a look at "The Eyes", NGC 4438 (which has arms) and NGC 4435 (which has not):2019-05-07_5cd1d0208a20f_TheEyes_S1_HVLG_SS1040_CBS_HVLG_Curves_s[1].jpgNGC 4438 and NGC 4435 are interacting. But only NGC 4438 looks disturbed,
because it has arms. NGC 4435 has not. Credit: KuriousGeorge.
Ann
Statistics: Posted by johnnydeep — Fri Sep 27, 2024 9:15 pm — Replies 11 — Views 357