Whew! While I figured good, clear nights would be a little hard to come by, I had no idea how rare a TRULY clear, dark night sky really is. Even when it’s “mostly clear” for the average person, the smallest cloud can ruin a whole night of imaging. Well, after nearly a month after ordering my astrophotography equipment, I have finally managed to image one of the most famous nebulas in the sky (albeit one that few people actually see with their own eyes as it’s so dim): Horse Head Nebula. My attempts, of which there have been a few this February, have been repeatedly snuffed by clouds. Even the lightest cloud cover that you can barely see ultimately ends up eliminating any chances of getting good images. Tonight’s clear sky gave me the window of opportunity I’ve been waiting for in order to bring you this image.
Horse Head is a part of a more complex collection of nebula in the IC434/Alnitak region of Orion’s belt. Alnitak is the eastern-most star of Orion’s belt, and to most observers, it looks like a lonely blue star. Up close, however, and it’s a much different story! Horse Head, along with it’s neighboring nebulas, are part of the greater Orion Molecular Cloud Complex. The red emission nebula that stretches behind horse head is called IC434. It glows reddish-pink (shows up red in my image due to certain necessary color corrections) due to a prevalence of electrified and ionized hydrogen gas, which emits visible light in narrow deep red and light blue bands. If it wasn’t for IC434, the famous Horse Head nebula would very likely not be famous, as it would just be more dark dust, invisible to all but the most intrepid and skilled deep sky astrophotographers.
Also visible in this image, just below the bright star Alnitak, is Flame Nebula. Having the appearance of a burning bush, and often called the Burning or Flaming Bush nebula in some parts of the world, it is a combination of dark nebula (like horse head) and emission nebula that emits light in more bands than IC434, giving it a rarer yellow-orange color. To the right of Flame and below Horse Head is IC 2023, a reflection nebula. At four light years across, it is one of the largest reflection nebula in the sky. The central star sits within a cavity of the dark nebula that ultimately forms the Horse Head itself, with fingers of that cavity reaching around in front from the lower right. To the left of Flame are two more nebula, seeming crosses between emission and reflection.
This is my first true deep sky exposure. For other astrophotographers out there who are interested, the image above is a stack of 30x180s RGB subs at ISO 400 using the Canon 7D and EF 600mm f/4 L II lens. Total integration time is 1 hour 30 minutes. Calibrated and stacked in DSS, processed with Photoshop CC.