Ring Nebula, M57 (NGC6720)
About this image
About this image
This is a two-minute exposure taken
on the night of September 26th 1994 (UT of observation 27/09/94:04:21).
This photograph shows a region 150 arc seconds square. The black-and-white
images have been compressed in brightness (approximately a double
logarithm) to show both bright and faint features.
Alternatively, the pseudo-color version of the same original
is used to show more of the fainter features while not saturating
the bright regions.
Although sky conditions were not the best that Kitt Peak can offer,
this image has a "seeing" measurement (average
FWHM of several stars) of about 0.8 arc seconds.
The image has not been re-oriented to remove either the CCD orientation
or the field rotation of the altitude-azimuth design of the WIYN telescope,
and is therefore shown with E up and S to the left.
About this object
The Ring Nebula, also known as M57 or NGC 6720, is found in the constellation
Lyra. A spherical shell of glowing gas surrounds a central hot star.
The nebula was formed when the central star ejected perhaps as much as
ten percent of its mass, over a period of some millions of years.
Initially slow mass loss creates a surrounding shell of material which
is later ionized by hotter, faster ejecta, which can result in quite
complex structures. The Ring Nebula was the first planetary
nebula discovered, so called because of its visual spherical appearance
through telescopes in the past. It has a diameter a little under one light-year
and is some 3000 light-years from Earth (angular size 1.2 arc minutes).
Location: 18 53.6 +33 02 (2000)
More: nebulae page, planetary nebulae page, stars page, messier page, WIYN nebulae page, WIYN planetary nebulae page, WIYN stars page, WIYN messier page.
Minimum credit line: WIYN/NOAO/NSF
Downloadable versions:
400 x 400 36kb 8 bit false color GIF (on this page)
200 x 200 34kb 8 bit B&W GIF
400 x 400 123kb 8 bit B&W GIF
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