|
Object |
Ngc
6357 |
|
Info |
Ngc 6357-
AKA as the Crab. This image is looking at the heart
of the object and its true shape is not defined. Ngc 6357 is
located in the constellation Scorpius, a large star forming region,
having an apparent size of about 50 arc minutes (about 400 light years).
At its centre is the open star cluster Pismis 24, birthing extremely
bright and blue stars. The overall nebula contains some of
the most massive stars ever discovered.
The overall red glow to the inner star forming region results from the
emission of ionized hydrogen gas.
The surrounding nebula has a complex network of gas, dark dust and
residing within this are newly forming and already formed stars. The
myriad of detailed patterns are the effect of interactions between
interstellar winds, radiation pressures, magnetic fields, and gravity. NGC
6357 is a very faint emission nebula, needing a large aperture telescope
or long exposure photography to reveal the faint structures. It lies about
8,000 L.yrs. away |
|
Date |
Ha- 13/ 5/
08 Lum-31/ 5/ 08 and GB data
31/ 6/ 08 |
|
Location |
BayTop
Observatory- Streaky Bay South Australia |
|
Instrument |
Home built 10" Newtonian (Bob
Royce primary) and an Antares 1/20th wave
secondary with MPCC
coma corrector. System working
@ native f4/
1016 FL 1.35 arcsec/pixel- FOV
23.3x29.4 |
|
Mount |
Celestron CI700 controlled by a Mel
Bartels Goto Control System
with Vexta PK264m-01b motors with a pulley and belt system |
|
Camera (CCD) |
Starlight
Xpress HX916 monochrome CCD with Atik manual
filter wheel. |
|
Exposures |
Ha:164 L:
80' Ha(R):32' G:32' B:32'
[4' sub exposures all unbinned and Sigma combined] No dark frames
removed. |
|
Guiding |
Orion 80ED refractor F7.5 with a
Starlight Xpress HX516
CCD. Mounted via a side by side accessory
plate. |
|
Filters |
Astronomik
typeII clr RGB filter set |
|
Notes/ Conditions |
Conditions- Taking the Ha seeing was
a little average but the transparency was good. Similar conditions taking
the lum. The night when taking the colour, I decided due to the
deteriorating conditions to only capture green and blue channels and use
the Ha data as a sub for the the red channel. Wind and dust produced more
than normal bloating to the G & B channels. Still very dry for winter
here. |
