| Designation |
Messier 81 (NGC 3031) Bode's Galaxy
|
| Type | Spiral Galaxy (type SA(s)ab I-II) |
| Constellation | Ursa Major |
| Coordinates | Telescope centered at RA '09 55 42' - Dec '+ 69 04 03' |
| Magnitude | 6.8 |
| Size | 36,000 light years across |
| Distance | 11.8 million light years (based on 32 cepheid variable stars calcs) |
| Dimensions | 24 x 13 arcminutes |
| Image Field | 22 x 16 arcminutes |
|
Notes:
|
M81 is one of the brightest galaxies visible from the Northern hemisphere. It is part of a galaxy cluster named after it. It forms a nice pairing in widefield scopes with it's neighbor M82, which is only 150,000 light years away. It is similar in size to our own Mily Way galaxy and shines with a luminosity equal to 250 billion suns. |
| Based on the calculated velocity of the stars and nebulae in the outer arms, M81 seems to have less dark matter than most other spiral galaxies (based on mass/gravetational pull). | |
|
|
The past interaction with neighboring M82 is evident from the dark lanes that run across and counter to it's arm's rotation. |
| 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 (V4.07) |
| 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, Ha
|
| Exposures |
Total
exposure time: 142 minutes: Luminance 60 (12 x 5) unbinned,
RGB - 18 (9x2) minutes each binned 2x2, Ha - 28
(7x4) minutes binned (2x2)
|
| Calibration | flats, bias |
| Processing Software | Maxim DL, Photoshop CS (8.0), NEAT image (color channel smoothing) |
| Location | Chiefland Astronomy Village, FL -29.393 N , - 82.863 W |
| Date/Time | 03/13/05 / '03:08' - '05:57' UT |
