Toggle menu
Call us at: 530 823 7796 ............... Open Mon-Fri 9-5 Pacific Time
SVX180T - Keyhole

SVX180T - Keyhole

Posted by Tony Hallas on 16th Jan 2024

Tony Hallas caught this striking image of the Keyhole Nebula (NGC 1999) in Orion with his SVX180T. This reflection nebula lies roughly 9,000 light-years away from Earth and has a diameter of about 7 light-years. In 2009, astronomers determined that the dark patch seen in this nebula is not black because it is an extremely dense pocket of gas, but because it is truly empty.

A nearby hypergiant star called Eta Carinae, another very well-known structure within the greater Carina Nebula, has caused the Keyhole Nebula to change over the centuries. This star is simply enormous, with a mass estimated to be up to 150 million times that of the Sun and a luminosity (brightness) 400 million times the Sun. This star emits a ton of radiation and that impacts all surrounding structures, including this nebula.


The N 1499 is RGB + SHO, the N 1999 is RGB + H-a. ZWO 6200 MM + Chroma filters.


Stewart, Suzy. Keyhole Nebula – Facts And Info. The Planets. Retrieved from

APOD: May 23, 1999 - The Keyhole Nebula. (n.d.).

Wikipedia contributors. (2024, January 7). Carina Nebula. Wikipedia.

Wikipedia contributors. (2023, December 20). NGC 1999. Wikipedia.