WIYN image of M15
This is a thirty-second exposure taken on the night of September 1st 1994 (UT of observation 02/09/94:05:47) with the 1k detector. This photograph shows a region 200 arc seconds square which has been compressed in brightness (approximately a double logarithm) to show both bright and faint features. This image shows the capabilities of the WIYN telescope rather better than most observations that night, since it has a "seeing" measurement of about 0.8 arc seconds.
Orientation: N up, W to the left.
F.L. Whipple Observatory image of M15.
This image was obtained by Bill Keel of the university of Alabama with the 4-meter Mayall telescope of Kitt Peak National Observatory. It is a 30-second red-light exposure (through clouds) with a Tektronix 2048x2048 CCD at the prime focus. The image has been block-averaged to 512x512 for this presentation, which uses a logarithmic intensity transformation to preserve information across a wide dynamic range. The field is 7.1 arcminutes square, showing the inner quarter of the original area images (pixels were averaged 2x2 for this display). Even with this short exposure, the bright core of the cluster saturated the CCD strongly enough for some of the charge to bleed along columns of the chip; this effect has been corrected in this display.
Globular star cluster M15, as seen by the KPNO 4-m Mayall telescope in 1975.
Orientation: north left, east down.
This picture of globular cluster M15 was made from CCD images taken at the
KPNO 0.9-meter telescope in July and September of 1998. The dynamic range has
been compressed considerably to show both the dense inner region of the cluster
and the much fainter outer areas. Image size is 15.9 arc minutes.
Last Modification: June 30, 2003