NGC 7822, also known as the Question Mark Nebula, is a young star forming complex in the constellation of Cepheus. The complex encompasses the emission region designated Sharpless 171, and the young cluster of stars named Berkeley 59. The complex is believed to be some 800–1000 pc distant,Majaess D., Turner D., Lane D., Moncrieff K. (2008). The Exciting Star of the Berkeley 59/Cepheus OB4 Complex and Other Chance Variable Star Discoveries, Journal of the American Association of Variable Star Observers, vol. 36, no. 1, p. 90Pandey et al.(2008).Stellar contents and star formation in the young star cluster Be 59, MNRAS, Volume 383, Issue 3, pp. 1241–1258 with the younger components aged no more than a few million years. The complex also includes one of the hottest stars discovered within 1 kpc of the Sun, namely BD+66 1673, which is an eclipsing binary system consisting of an O5V that exhibits a surface temperature of nearly 45,000 K and a luminosity about 100,000 times that of the Sun. The star is one of the primary sources illuminating the nebula and shaping the complex's famed pillars of creation-type formations, the elephant trunks.Gahm G. F., Carlqvist P., Johansson L. E. B., Nikolić S. (2008). Rotating elephant trunks, Astronomy and Astrophysics, Volume 454, Issue 1, July IV 2006, pp.201-212Fernandez, Antonio (2008). Sharpless 171, APOD, October 18, 2008
Sharpless 2-170, or the Little Rosette Nebula. is located nearby. The two nebulae are not related, with NGC 7822 being about 4,600 Light Years away from each other.
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