Skies By Africa

Images of the Heavens By Eric Africa

The NGC 1999 Region

NGC 1999
NGC 1999 (the bright blue object in the center of this image) is a a reflection nebula about 2 degrees south of the famous Orion Nebula. Its most striking feature is the keyhole-shaped cavity at its center. This cavity was previously thought to be a dark nebula, one of those many dust clouds that obscure the light from stars behind them. However, recent studies of that cavity indicate that it is indeed a hole in the nebula! Current theories are that a nearby star (specifically, one of the three stars that make up V380 Orionis, a triple-star system that is responsible for lighting up NGC 1999) has a polar jet that is creating the hole!

Speaking of polar jets, see the knots of bright red nebulosity just to the left of NGC 1999? Those are designated as HH1 and HH2, short for Herbig-Haro 1 and Herbig-Haro 2. HH-1 and HH-2 were identified by Guillermo Haro and George Herbig in the 1950's. These objects are now known to represent jets of gas being ejected by protostars (baby stars) and are recognized as part of star formation. Imagine a disk of dust obscuring the protostar. This baby star is shooting out jets of gas at high speed (estimated at 100,000 miles per hour or more) from its poles. The high-speed gas is colliding with and heating up the ambient gas and dust in the surrounding area and causing that gas to glow. Thus, Herbig-Haro objects are usually associated with star formation. The two HH objects in this image are actually associated with the same protostar (hidden somewhere in the dark region that is obscuring dust between the two HH objects). Think of the jet as being aligned almost horizontally as composed; the protostar is in the dark region between them.

All the nebulosity visible in this image is part of a huge Orion molecular cloud complex that includes other notable targets as the Orion Nebula and the Horsehead nebula.

Source: Robert Gendler, Wikipedia

 
Constellation: Orion
When Visible: December - April
Distance: 1,500 Light-years
Date: January 2014
Location: Rancho Hidalgo, Animas, NM
Exposure Details:
L :21 x 10 Minutes Binned 1 x 1
Red: 12 x 10 Minutes Binned 1x1
Green: 12 x 10 Minutes Binned 1x1
Blue: 12 x 10 Minutes Binned 1x1

9 Hours and 30 Minutes Total Exposure Time
 
Equipment Used:  12.5" PlaneWave CDK on a Paramount ME mount. SBIG STL-6303 camera with 5-position filter wheel and Astrodon filters. Internally guided with the SBIG internal guide chip.
 
Acquisition Software : MaximDL 5, TheSky6, CCDAutopilot 5, FocusMax
Processing Software: MaximDL, Photoshop CS5, Carboni Actions, IrFanView, AviStack
 
The large image linked to above to is only 75% of the original sized image. Here are 100% sized crops of the more interesting features:
Keyhole NGC 1999 and the "Keyhole" HH-1 and HH-2 HH-1 and HH-2