| Designation |
Messier 57 (NGC 6720) - The Ring Nebula (small
galaxy IC1296)
|
| Type | Planetary Nebula |
| Constellation | Lyra |
| Coordinates | Telescope centered at RA '18 53 20' - Dec '+ 33 03 09' |
| Magnitude | 8.8 |
| Size | .9 light years (5.5 trillion miles) |
| Distance | 2,300 light years |
| Dimensions | 1.4 x 1.0 arcminutes |
| Image Field | 11 x 12 arcminutes (cropped) |
|
Notes:
|
The Ring is exposing a decreasing ionization level with increasing distance from the 100,000 to 120,000 K hot central star. The innermost region appears dark as it emits merely UV radiation, while in the inner visible ring, greenish light of ionized oxygen and nitrogen dominates the color, and in the outer region, only the red light of hydrogene can be excited. |
| The central star is a planet-sized white dwarf star, which shines at about 15th magnitude. It is the remainder of a sunlike star, probably once of more mass than our sun, which has blown away its outer envelopes at the end of its Mira-like phase of evolution. Now over 100,000 K hot, it will soon start to cool down, shine as a white dwarf star for a while of several billions of years, and then eventually end as a cold Black Dwarf. (SEDS) | |
|
|
The nebula is roughly 6,000 - 8,000 year old |
| Telescopes | Meade 10" LX200 f/10 on Losmandy G-11 with Gemini L3 |
| Focal Length | 1575 mm @ f/6.3 |
| Guiding | SXV guidehead through Takahashi FS60C @ f/5.9 |
| Telescope Control | Maxim DL (V3) |
| CCD Camera |
Starlight
Xpress SXV-H9 - USB 2 ExView progressive scan
1392 x 1040 (6.45 uM)
pixel array (8.98 x 6.71 active area)
|
| Image Scale | .88 arcsec/pixel |
| Filters |
1.25"
Astronomik Type II Dichroic IR blocking filters in Astronomik filter
drawer - Clear, Red, Green, Blue
|
| Exposures |
75 minutes Luminance unbinned,
R,G,B (20, 20, 24 minutes binned 2x2)
|
| Calibration | None |
| Processing Software | Maxim DL, Photoshop CS (8.0) |
| Location | Chiefland Astronomy Village, FL - 29.393 N , - 82.863 W |
| Date/Time |
03/20/04
/ '08:06' - '10:24' Universal time
Some of the best seeing I have ever
experienced
|
