NGC 7006

NGC 7006
Hubble image of NGC 7006
Observation data (J2000 epoch)
ClassI[1]
ConstellationDelphinus
Right ascension21h 1m 29.4s[2]
Declination+16° 11′ 14.4″[2]
Distance137×103 ly (42 kpc)[3]
Apparent magnitude (V)10.6[4]
Apparent dimensions (V)2.8′[4]
Physical characteristics
Mass3.03×105[5] M
Metallicity${\displaystyle {\begin{smallmatrix}\left[{\ce {Fe}}/{\ce {H}}\right]\end{smallmatrix}}}$ = –1.52[5] dex
Other designationsCaldwell 42
See also: Globular cluster, List of globular clusters

NGC 7006 (also known as Caldwell 42) is a globular cluster[2] in the constellation Delphinus. NGC 7006 resides in the outskirts of the Milky Way. It is about 135,000[6] light-years away, five times the distance between the Sun and the centre of the galaxy, and it is part of the galactic halo. This roughly spherical region of the Milky Way is made up of dark matter, gas and sparsely distributed stellar clusters.

NGC 7006 appears in the science fiction novel Beyond the Farthest Star by Edgar Rice Burroughs, where it is used as a point of reference by the inhabitants of the planet Poloda to determine the approximate location of Earth.[7]

References

1. ^ Shapley, Harlow; Sawyer, Helen B. (August 1927), "A Classification of Globular Clusters", Harvard College Observatory Bulletin, 849 (849): 11–14, Bibcode:1927BHarO.849...11S
2. ^ a b c "NGC 7006". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2007-04-21.
3. ^ Hessels, J. W. T.; et al. (November 2007), "A 1.4 GHz Arecibo Survey for Pulsars in Globular Clusters", The Astrophysical Journal, 670 (1): 363–378, arXiv:0707.1602, Bibcode:2007ApJ...670..363H, doi:10.1086/521780, S2CID 16914232.
4. ^ a b "Results for NGC 7006". SEDS NGC Catalog Online. Retrieved 2010-11-27.
5. ^ a b Boyles, J.; et al. (November 2011), "Young Radio Pulsars in Galactic Globular Clusters", The Astrophysical Journal, 742 (1): 51, arXiv:1108.4402, Bibcode:2011ApJ...742...51B, doi:10.1088/0004-637X/742/1/51, S2CID 118649860.
6. ^ "A Remote Outpost of the Milky Way". ESA/Hubble Picture of the Week. 12 September 2011. Retrieved 13 September 2011.
7. ^ Burroughs, Edgar Rice (2012). Beyond the Farthest Star. eStar Books. p. 47. ISBN 978-1-61210-538-3.