Interacting galaxy NGC91

About this image

About this image
This is a one-minute exposure taken on the night of September 1st 1994 (UT of observation 02/09/94:09:39) with the 1k detector. This photograph shows a region 100 arc seconds square, which is displayed in pseudo-color, where the brightness is mapped to a color so as to show more of the fainter features (in green) while not saturating the bright regions (red, shading to grey/white). Observing conditions during this phase of the commissioning were not ideal, but this image has a "seeing" measurement (average FWHM of several stars) of about 0.9 arc seconds.
Orientation: N up, with E to the left.

About this object
NGC91 (Arp 65) is an unusual spiral galaxy in the constellation Pegasus. It is classified as SAB(s)c(pec), which means that it is a spiral ("S") with a central bar, not well developed ("AB"), where the arms start at the ends of the bar (the "(s)"), and are few in number and quite open (the final "c"). The "(pec)", or peculiar, features include the extended material seen to the upper right (NW) in this image, as well as a second fainter trail going to the bottom left (SE), which is only hinted at in this short exposure. There are several other galaxies nearby, which may account for its oddities (although not everyone thinks we can always blame interactions for strange morphologies).

Location: 00 21 51.7 +22 24 01 (2000.0), distance: over 200 million light-years,
size: perhaps 60000 light-years across.

More: galaxies page, spiral galaxies page, WIYN galaxies page, WIYN spiral galaxies page.

Minimum credit line: WIYN/NOAO/NSF

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200 x 200 9kb 8 bit false color GIF (on this page)
400 x 400 33kb 8 bit false color GIF
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