Selztal Observation Site

Welcome - Enjoy your visit

Arp 273

Stimulated by pictures from other observers, I learned that within constellation Andromeda beside famous M31 and NGC 891 some more remarkable galaxies can be found: Arp 273 (or UGC 1810 & 13).  In a distance of roughly 300 mil ly away we see two interacting galaxies which looks like to got some tidal interaction some mil years ago. This pair of galaxies have described first time in the Atlas of Peculiar Galaxies compiled by Halton Arp in middle 1966 On the top we have UGC1810, a disturbed spiral and below it's UGC 1813.

(Click on image for larger version)

From Hubble Space Telescope Photo Releases heic1107 it's stated that UGC1810 is roughly 5 times more massive. I personally more impressed by the upper spiral arm of UGC1810 which shows a lot of blue spot's as indicator of starformation some mil years ago.. (the star could not be very much older because other their high luminosity. To see such a wide distributed region of starformation which I read as an indicator of an strong interaction some mil years ago which triggered this star formation and looking at the warped UGC1813 is not very unlikely.          

This image was taken on December 29th, using my STL 11000L, 510/2030mm Newton on a ASA DDM85 direct drive mount, 10x300s Luminance channel.

I estimated the limiting magnitude to roughly 20.5 @ a S/N=5. It looks like that this is close to my current limit because of the background brightness driven my streetlamps close to my property.