Object name: MRK273

Designation(s): MRK273, IC0921, IC926, IC929, IC930, ID931, IC932, IC934, IC936, IC937, UC938, ABELL1783,

Markaryan 273 is a well studied but mostly ignored by amateurs galactic merger in progress located in Ursa Major about 3 degrees northwest of M101. Redshift puts it about 516 million light-years distant. The core shows two nuclei one second apart. Far beyond my resolution this night. They consist of very different age stars. One of the merging galaxies is thought to have been unusually gas rich. A note at NED indicates there's a ring of star formation some 100 kpc (326,000 light-years) in diameter thanks to all the gas. I measure the southern plume as being some 144,000 light-years long though a note at NED puts it at 130,000. The difference may be due to the distance estimate used. As with all my redshift distances I used NED's 5 year WMAP calculator. I measure the northeastern fainter plume as being even longer at 165,000 light-years. Since they aren't 180 degrees apart I find the distance between their endpoints to be 103.7" of arc which works out to 259,000 light-years. The merging galaxies are considered very strong in all wavelengths from radio well into the ultraviolet. It is classed as an ultraviolet excess object, an IR source and a radio source. All but the gamma ray astronomers have put a lot of time into studying this object. There is a lot of information at NED on this galaxy, far too much for me to cover. Those interested can go to NED and look up MRK 273 and click on the notes link in the list of links at the upper right of the page. Several other galaxies with the same redshift as MRK 273 are in the area a few of which are in the frame.

I placed the galaxy well to the north of the center of the field to also pick up the core of the Abell 1783 galaxy cluster. This cluster's core consists of quite a few IC galaxies all of which are listed in NED as; "Identification as IC 0nnn is not certain." SEDS says of these; "Unidentified at the place given, or type unknown, in Ursa Major." Due to this, I've listed them with a question mark in the annotated image. The cluster's distance is about 920 million light-years. All the IC galaxies in this cluster were discovered in 1892 by Edward Barnard. He was a very careful observer so how these identifications became so questionable I don't know. With a radius of 35 minutes of arc MRK 273 is within the cluster but lies only about half as far away so the two are unrelated. All these IC galaxies were discovered by Edwin Barnard in June 1802. How such a careful observer came up with uncertain data I don't know. IC 936 may be a duplicate of IC 934 according to Seligman, if so what is the other one and which is the correct whatever IC number is used? It's all very confusing. Other IC galaxies credited to Barnard this night are just out of the image to the south. None of the identifications is certain, hence the question mark in the annotated image.

Well below MRK 0273 is the strange galaxy ASK 300802. Is that a plume going to the north-northeast or is it a separate galaxy? I consulted the Sloan image and couldn't tell. But according to NED, they say it is a star! Try as I may, I can't turn a fuzz patch into a star. So it is a mystery object, plume or separate galaxy but certainly not a star.

The frame contains several very blue star-like objects that appear to be quasars but aren't so listed at NED. Instead, they are listed as BLAGN (Broad Line Active Galactic Nuclei. Since they appear very quasar-like and are as bright as quasars I also show them as (Q?) in the annotated image. If a galaxy had a catalog designation that wasn't just its position I've shown that but if it is listed only by its coordinates I've just listed it as G followed by its distance. If a galaxy was in the IC but had no distance data it is listed with na where the distance would have been shown if it had been available. I've listed NED's classification of the object if given after its catalog name or "G" when available.

To show the faint northeastern plume of MRK 0273 I've stretched the image more than normal which also helps to show the noise in the image due to my short exposure time. I'd planned much more time but, as usual, this year, the weather conditions made that impossible. I had to fight for what little I got.

Also, the F7 star just east of MRK 273 sent horrid reflections all across the frame. The multitude of overlapping donuts it created was a major processing pain and cost me some faint detail. More time would have made those reflections even worse.

14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME

Related Designation(s):

1AXG J134440+5553, 1RXS J012337.2+331508, 1XMM J012339.9+331521, 2MASS J01233993+3315218, 2MASS J13430798+5539043, 2MASS J13433925+5537535, 2MASS J13434500+5538016, 2MASS J13434553+5538473, 2MASS J13435121+5538483, 2MASS J13435239+5539245, 2MASS J13440853+5542221, 2MASS J13442892+5537486, 2MASX J01233995+3315222, 2MASX J13430804+5539043, 2MASX J13433923+5537534, 2MASX J13434501+5538014, 2MASX J13434549+5538474, 2MASX J13435116+5538483, 2MASX J13435235+5539243, 2MASX J13442896+5537482, 2MASX J13444207+5553131, 2MASXi J1343080+553904, 2MASXi J1343392+553753, 2MASXi J1343450+553801, 2MASXi J1343454+553846, 2MASXi J1343511+553848, 2MASXi J1343523+553924, 2MASXi J1344289+553748, 2MASXi J1344420+555313, 2PBC J1344.2+5551, 2XMM J012339.9+331521, 2XMM J134442.1+555312, 2XMMp J012339.9+331521, 2XMMp J134442.1+555312, 6C B012050.2+325930, 6C B134252.4+560807, 6C* 0120+329, 87GB 134253.6+560828, 87GB[BWE91] 1342+5608, ABELL 1783, ABELL1783, AKARI J1344424+555316, ARP 229 NED01, ASK 300441.0, ASK 300446.0, ASK 300481.0, ASK 300811.0, ASK 300906.0, ASK 300910.0, ASK 301120.0, B2 0120+30:[MLO2002] NED45, B2 0120+33, C-GOALS 22, CGCG 0120.8+3300, CGCG 1342.8+5608, CGCG 271-060, CGCG 272-005, CGCG 502-067, CGPG 1342.8+5608, CXOMP J134442.0+555313, GALEX J012340.03+331523.0, GALEX J012340.1+331522, GALEXASC J012339.79+331521.8 , GALEXASC J134339.06+553754.4 , GALEXASC J134345.58+553848.1 , GALEXASC J134351.79+553848.9 , GALEXASC J134408.51+554221.6 , GB6 J1344+5553, HDCE 0070 NED021, I Zw 071, IC 0921, IC 0926, IC 0929, IC 0930, IC 0932, IC 0934, IC 0935, IC 0936, IC 0937, IC0921, IC926, IC929, IC930, IC932, IC934, IC936, IC937, ID931, IRAS 13428+5608, IRAS F13428+5608, ISOSS 058, ISOSS J13447+5553, LDCE 0074 NED071, LEDA 2509027, LEDA 2509480, LEDA 2509643, LEDA 2511548, LGG 026:[G93] 004, LQAC 206+055 003, MAPS-NGP O_134_0024335, MCG +05-04-044, MCG +09-23-004, MCXC J1343.7+5538, Mr19:[BFW2006] 20347 NED02, Mr20:[BFW2006] 32589 NED03, Mr20:[BFW2006] 32589 NED09, Mr20:[BFW2006] 32589 NED10, Mr20:[BFW2006] 32589 NED11, Mr20:[BFW2006] 32589 NED15, Mr20:[BFW2006] 32589 NED16, Mr20:[BFW2006] 32589 NED17, MRK 0273, Mrk 273, MRK273, NGC 0507, NGC 0507 GROUP:[ZAC2011] BCG , NGC 0507:[PFP2003] 10, NSA 052928, NSA 129359, NVSS J134442+555313, PGC 005098, PGC 048711, RIXOS F254_524, RSCG 08:[WBJ2013] A, RX J0123.6+3315, RX J0123.6+3315:[BEV98] 002, RX J0123.6+3315:[CAE99], RX J1343.7+5538, RX J134334.1+553644, SAFIRES J134442.25+555314.1, SBS 1342+561, SCL 133 NED02, SDSS J012339.90+331519.2, SDSS J134307.98+553904.5, SDSS J134307.99+553904.3, SDSS J134308.00+553904.4, SDSS J134339.24+553753.6, SDSS J134339.26+553753.4, SDSS J134339.27+553753.5, SDSS J134345.00+553801.8, SDSS J134345.01+553801.6, SDSS J134345.02+553801.6, SDSS J134345.53+553847.6, SDSS J134345.54+553847.4, SDSS J134345.55+553847.4, SDSS J134345.55+553847.5, SDSS J134351.23+553848.5, SDSS J134352.37+553924.7, SDSS J134352.38+553924.5, SDSS J134352.39+553924.5, SDSS J134408.53+554222.1, SDSS J134408.54+554221.9, SDSS J134408.55+554221.9, SDSS J134408.55+554222.0, SDSS J134428.90+553748.9, SDSS J134428.92+553748.6, SDSS J134428.92+553748.7, SDSS J134428.93+553748.7, SDSS J134442.15+555313.8, SDSS J134442.16+555313.5, SDSS J134442.16+555313.6, SPIDER J205.91362+55.63152, SSTSL2 J012339.87+331522.2, TXS 1342+561, UC938, UGC 00938, UGC 08696, USGC U059 NED36, UZC J012340.1+331520, UZC J134442.0+555312, VV 207a, VV 851, WBL 038-015, ZwCl 1341.9+5550, [A2001] J134442.1+555313, [BDG98] J012340.0+331520, [BFW2006] J205.78325+55.65126 , [BFW2006] J205.91353+55.63157 , [BFW2006] J205.93750+55.63384 , [BFW2006] J205.93971+55.64657 , [BFW2006] J205.96822+55.65687 , [BFW2006] J206.03557+55.70616 , [BFW2006] J206.12045+55.63025 , [dML87] 678, [FBS2007] 50, [FCC2009] 009, [FPK2009] 93747, [GMM2009b] 62, [GMM2009] 0817896, [GMM2009] 0819603, [GMM2015] J134442.1+555313, [HRT2007] J134444+555322, [JBB2007] J134442.12+555313.4 , [MLO2002] J012340.0+331520, [OYS2015] J206.17569+55.88711 , [RC2] A1342+56, [RHM2006] ULIRGs 005, [SLH97] H01064, [SLK2004] 0893, [TCW2007] 149, [TTL2012] 070237, [TTL2012] 070297, [TTL2012] 081740, [TTL2012] 081741, [TTL2012] 081744, [TTL2012] 082501, [TTL2012] 085651, [TTL2012] 090687, [VCV2001] J134442.1+555313, [VCV2006] J134442.1+555313, [WB92] 0120+3257, [WB92] 1342+5608, [WLH2009] 0695 NED01, [YSS2008] 045,