DescriptionImages

Object name: NGC5857

Designation(s): NGC5857, NGC5859,

NGC 5857 and NGC 5859 are a pair of non-interacting galaxies. By redshift, they are very close neighbors though Tully Fisher measurements indicate they may be very widely separated. All Tully Fisher measurements for both were made the same way. Those listed for 5859 have three that put it much closer than redshift says, the fourth agrees with redshift measurements. Using the same system by the same authors the four measurements of 5857 agree quite well. If the closer Tully Fisher distances are used for 5859 then the two galaxies are about the same size. 5859 would be 120,000 light-years in diameter with NGC 5857 being 97,000 light-years in diameter. Using the far distance for 5859 its diameter is 174,000 light-years. That seems way too big to me. Until I learn differently I'm going to say the Tully Fisher measurement for NGC 5859 is more likely representative of its true distance and size.

Another issue with NGC 5859 is its status as a barred spiral. I can't see any hint of a bar. It appears to me the arms go in right to the core though it is so edge on this may be misleading. One note at NED also disagrees with the barred spiral classification saying they can't detect a bar either.

NGC 5857 and NGC 5859 were discovered by William Herschel on April 27, 1788. Neither are in either H400 program.

There are two other galaxies in the image at about the distance of NGC 5857. They are much smaller and while blue are of lower surface brightness as well. The only carry Sloan positions and ASK numbers for their catalog entries.

Many other interesting galaxies are in the field, most I wanted to know about had no redshift data, unfortunately. For some reason, I took one more blue frame than normal. I must have thought one of the first two was not usable but all three were of similar quality and similar to the other colors as well. Might be I just hit the wrong key.

14" LX200R @ f/10, L=4x10' RG=2x10' B=3x10', STL-11000XM, Paramount ME