IRAS 18333-2357
Planetary Nebula IRAS 18333-2357
(PK 009-07.1, GJJC 1) in globular cluster
M22
in Sagittarius
Right Ascension |
18 : 36.3 (h:m)
|
Declination |
-23 : 55.5 (deg:m)
|
Distance |
10.1 (kly)
|
Visual Brightness |
15. (mag)
|
Apparent Dimension |
3 (arc seconds)
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Planetary nebula IRAS 18333-2357 or GJJC1 in M22 was discovered by the infrared
satellite IRAS (Gillett et.al., 1989).
This faint object is of about 15th visual magnitude and only 3 arc seconds
diameter. Lying 1' south of the center of M22, the nebula is an extreme
observer's challenge:
It is Rich Jakiel's
Ultimate Challenge No. 7.
Doug Snyder has an excellent
IRAS 18333-2357
information page and a detailed
IRAS 18333-2357
observer's page with locating info and images; we adopted the image
on the right from there.
Below we present images of the faint planetary nebula
IRAS 18333-2357, from George Jacoby's
planetary nebulae sampler:
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This is a small region in the globular cluster M22, a dense star cluster
about 3 kpc away. Near the center is a very unusual planetary nebula
discovered by its distinctive infra-red emission with the IRAS satellite.
The nebula is almost undetectable in this image.
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This is the exact same picture as the M22 picture above, but a continuum
image was subtracted from the {OIII} image above to enhance the visibility
of the emission-line nebula. The "dual headlight" white spots just above
the center of the picture show the brightest parts of the nebula, but there
are also faint wisps tailing away and downward. This nebula is extremely
bizarre in that (1) it is only 1 of 2 known in globular clusters, (2) it is
only 1 of 4 known to be completely devoid of hydrogen, and (3) it is only
1 of about 3 known to be sweeping through the interstellar medium. The
central star is the bright star in the middle of the picture.
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Credit: George Jacoby, KPNO
More info on these images
(George Jacoby)
More images by George Jacoby
Links:
References:
- F.C. Gillett, G.H. Jacoby, R.R. Joyce, J.G. Cohen,
G. Neugebauer, B.T. Soifer, T. Nakajima, and K. Matthews, 1989.
The optical/infrared counterpart(s) of IRAS 18333-2357.
Astrophysical Journal, Vol. 338, pp. 862-874 (March 15, 1989)
[ADS: 1989ApJ...338..862G]
Planetary Nebula Pease 1 in M15
Planetary Nebulae in Globular Clusters
Hartmut Frommert
Christine Kronberg
[contact]
Last Modification: October 27, 2005