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Hourglass Nebula

The Engraved Hourglass Nebula (also known as MyCn 18) is a young planetary nebula situated in the southern constellation Musca about 8,000 light-years away from Earth. It was discovered by Annie Jump Cannon and Margaret W. Mayall during their work on an extended Henry Draper Catalogue. At the time it was designated simply as a small faint planetary nebula. Much improved telescopes and imaging techniques allowed the hourglass shape of the nebula to be discovered by Raghvendra Sahai and John Trauger of the Jet Propulsion Laboratory on July 30, 1995. It is conjectured that MyCn 18's hourglass shape is produced by the expansion of a fast stellar wind within a slowly expanding cloud which is denser near its equator than its poles.

The Hourglass Nebula was photographed by the Wide Field and Planetary Camera 2 of the Hubble Space Telescope.

Hourglass Nebula
Observation data
(Epoch J2000)
Right ascension 13h 39m 35.116s[1]
Declination -67° 22′ 51.45″[1]
Distance 8 kly (2.5 kpc)
Apparent magnitude (V) 13.0[1]
Constellation Musca
Physical characteristics
Radius -
Absolute magnitude (V) -
Notable features -
Other designations ESO 97-1,[1]

Engraved Hourglass Nebula,[1]
Etched Hourglass Nebula,[1]

PN MyCn 18[1]

It should be noted there is another nebula which shares the designation of hourglass nebula [1] it can be found in the Lagoon Nebula [2]

Hourglass Nebula in popular culture

* The Hourglass Nebula was featured on the cover of the April 1997 issue of National Geographic. The nebula’s unique appearance led the magazine’s editors to comment, “Astronomers looked 8,000 light-years into the cosmos with the Hubble Space Telescope, and it seemed that the eye of God was staring back.”

* The Hourglass Nebula also serves as the front cover for Pearl Jam's 2000 album Binaural.

See also

* Hourglass Nebula in fiction.

* Eye of Providence


1. STScI. Hubble Finds an Hourglass Nebula around a Dying Star. Press release: Space Telescope Science Institute. January 16, 1996.

1. ^ a b c d e f g SIMBAD Astronomical Database. Results for PN MyCn 18. Retrieved on 2006-12-22

Astronomy Encyclopedia

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