NGC 1999 area with Waterfall Nebula (HH 222)

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About this Image

2 degree south to the famous Orion Nebula complex (M42, M43) a faint structure of dust and gas is situated, being in nice contrast with blue reflecting gas.
All these structures belong to the Orion Molecular Cloud 1 (OMC 1). The age of this cloud is at several million years.
At the center of this image lies the famous Waterfall Nebula, cataloged as Herbig-Haro 222. HH34 is the tiny arc just below and right of the water fall. Many other Herbig Haro objects (HH) are visible as red streaks within the center part of this image. Typically a young star is surrounded by layers of dust and gas. This star, though, somehow ejects energetic "bullets" of high-energy particles, appearing as red streaks toward the lower right of the this image. Astronomers speculate that a burst of these particles might rebound when gas from a disk surrounding the star momentarily collapses onto the star. The mechanism of formation of the Waterfall Nebula itself still is unknown.

The brghtest blue-white patch below the center is the reflection nebula NGC1999, illuminated by the star V380 Orionis.
The distance to this area is estimated at 1600 light years. North is up.

Find a Hubble image of NGC1999 here: 1.
Find a famous image of the Waterfall Nebula from the VLT taken in 1999 here: 2.
Literature on the Herbig Haro objects and catalogue: 3.

Find below a crop on the center of the above image in 50/100% size.

clic for 100% size 1113 x 1314 (274 kB)


Technical Details


16" cassegrain in corrected primary focus at f/3

Mount MK-100 GEM
Camera SBIG STL-11000M at -25C, internal filter wheel
Filters Astronomik LRGB+Ha
Date March 2007.
Location Wildon/Austria
Sky Conditions mag 5-5.5 sky, seeing 2-3" FWHM
Exposure Ha:R:G:B = 90:40:30:40 (10 min sub-exposures for R,G,B, 30 min for Ha),
Processing Image aquisition in Maxim 4.5; Calibration and preprocessing in CCDStack;
Other in Photoshop; Noise reduction by Neatimage;