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Time Travel
Research Center © 2005 Cetin BAL - GSM: +90
05366063183 - Turkey / Denizli
Elephant Trunk Nebula (Van den Berg 142)
Characteristics:
Magnitude: Unknown.
Size: Roughly about 45 arcminutes (Elephant Trunk itself). The Elephant
Trunk is located within the faint IC1396 emission nebula, which is about 3
degrees across.
Distance: 2,450 light years
RA: 21h 35m 37s
Dec: 57degrees 24' 03"
Description:
The Elephant Trunk Nebula is located within the large IC1396 emission nebula
complex. This beautiful area of hydrogen gas and dust is a stellar nursery
that holds many young nascent stars. The top region of the Elephant Trunk
is being blown away by radiation emitted from new-born stars
that are
igniting deep within the nebula.
Although the dark gas and dust are opaque to visible light, infrared light
passes through this region easily, permitting a view of the inner workings
of the Elephant Trunk.
Please click here for an infrared view of this area taken through the Space
InfraRed Telescope Facility (SIRTF), now known as the Spitzer Space
Telescope.
Photographic Details:
Date: May 29, 2004 (Ha image); June 18, 2004 (RGB image)
Scope: Takahashi Sky 90 at f4.5 with field flattener/focal reducer, on the
G11 Losmandy Mount.
Autoguider: STV with e-finder.
Camera: SXV-H9.
Filters: Astronomik Ha filter (13 nm bandpass).
Exposures: Ha:(HaR:G:B). Ha image: 18 x 5' each, unbinned. RGB image: 5
x 5' each channel (25 minutes per channel), unbinned. Total exposure 165
minutes.
Conditions: May 29: Temperature 55 degrees
F; above average transparency; above average seeing; intermittent breeze.
Post-processing: No dark, bias, or flat frames used. Two-star aligned in
MaximDL; Sigma combined using RC Sigma Reject plug-in for MaximDL, followed
by DDP in ImagesPlus (IP). Subsequent levels and curves adjustments in
Photoshop CS (16 bit format). Ha was combined with RGB using the technique
of Luminance Corrected RGB. Star color was good in the RGB image but muted
in the Ha:(HaR:G:B) composite. In order to recapture star color, I
used the original RGB image as a layer on top of the Ha:(HaR:G:B) composite,
selected the stars in the RGB image using the magic wand, used this as a
mask for the RGB image, and then assigned "color" mode for the RGB image
layer. This restored the original star colors of the underlying Ha:(HaR:G:B)
composite without affecting the rest of the image.
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