Dew Nebula (NGC 1514)

History

The object was discovered by William Herschel on 13 November 1790 and cataloged as IV 69. It marked a turning point in his astronomical thinking, because until then astronomers believed that all nebulae were composed of faint single stars that could not be resolved with the devices of the time. Herschel described NGC 1514 as follows: «A most singular phenomenon; A star 8m with a faint luminous atmosphere of a circular form, about 3' in diameter. The star is perfectly in the centre, and the atmosphere is so diluted, faint and equal throughout, that there can be no surmise of its consisting of stars, nor can there be a doubt of the evident connection between the atmosphere and the star. Another star, not much less in brightness, an in the same field with the above, ws perfectly free from any such appearance.» [465]

NGC 1514
NGC 1514: Dew Nebula in Taurus; 500 mm Cassegrain 5800 mm f/11.4; SBIG STL11K; 75+20+20+20 min LRGB; Bernese Highlands; © 2005 Radek Chromik
NGC 1514
NGC 1514: Dew Nebula in Taurus; Takahashi Mewlon 250 CR, Reducer CR 0.73 (f=1800mm / f7.25), SBIG ST-8300; 11L x 600sec 1×1, 10R, 5G, 4B 2×2 x 600sec; Bernese Highlands; © 2020 Bernhard Blank, Dragan Vogel

Physical Properties

NGC 1514
NGC 1514: Images in visible light (left) and infrared (right). Excerpts from PanSTARRS DR1 color and allWISE color [147]

NGC 1514 is a 114 to 132 arc seconds sized planetary nebula 2000 light years away. It has an integrated visual brightness of 10.9 mag and a central star that is considerably bright at 9.4 mag. The nebula shines very strongly in the O-III range (doubly ionized oxygen), but also in the H-alpha and H-beta range (light of neutral hydrogen at 656.3 nm and 486.1 nm, respectively). In the O-III range, an expansion speed of the nebula of 25,000 m/s has been calculated, while the nebula as a whole including the central star is moving away from us at 60,000 m/s. The central star of NGC 1514 is particularly interesting. It is a very narrow double star that cannot be separated in telescopes. An A-star and an O-subdwarf star orbit their common center of gravity in just 9h 50m.

«Strasbourg-ESO Catalogue of Galactic Planetary Nebulae» Acker et al., 1992 [141]
DesignationsPN G165.5-15.2: NGC 1514, PK 165-15.1, ARO 21, VV 17, VV' 23
Right Ascension (J2000.0)04h 09m 17s
Declination (J2000.0)+30° 46' 35"
Dimensions 132." (optical), 160." (radio)
Distance 0.66 kpc
Radial Velocity+59.8 km/s ± 4.4 km/s
Expansion Velocity 25.0 km/s (O-III)
C-Star DesignationsAG +30 402, AG82 28, BD +30 623, FB 33, FB 34, HD 281679, PLX 915, SAO 57020
C-Star Magnitude9.87 mag (U filter), 9.93 mag (B filter), 9.42 mag (V filter)
C-Star Spectral TypesdO + A0 III
DiscovererPICKERING 1879

Finder Chart

NGC 1514 is located in the constellation Taurus on the border with the constellation Perseus. If you extend the connection between the two stars ο - ζ Persei by about 1.5 times, the PN should already be visible in a large field eyepiece.

If you don't know what kind of sight to expect at NGC 1514, the search for this PN can sometimes be quite lengthy, even though the nebula is in a familiar area of the sky. Without the O-III filter, the nebula around the bright central star looks as if the eyepiece were slightly fogged up. Hence it was nicknamed «Dew Nebula». If there is no O-III filter available, you should primarily look out for the distinctive star pattern in the 1° closeup. Of the three stars north/south direction, the middle central star is NGC 1514.

Chart Dew Nebula (NGC 1514)
Dew Nebula (NGC 1514) in constellation Taurus. Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

More Objects Nearby (±15°)

References

141Strasbourg-ESO Catalogue of Galactic Planetary Nebulae; A. Acker, F. Ochsenbein, B. Stenholm, R. Tylenda, J. Marcout, C. Schohn; European Southern Observatory; ISBN 3-923524-41-2 (1992); cdsarc.unistra.fr/viz-bin/cat/V/84 (2021-02-18)
147Aladin Lite; aladin.u-strasbg.fr/AladinLite (2020-12-23)
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
465«Catalogue of 500 new nebulae, nebulous stars, planetary nebula:, and clusters of stars; with remarks on the construction of the heavens» William Herschel, Philosophical Transactions of the Royal Society of London, 1 January 1802; DOI:10.1098/rstl.1802.0021