M101 Spiral Galaxy (LRGB)
Messier 101 is a prominent face-on spiral galaxy in the constellation Ursa Major. One of the last entries in Messier's list of comet "imposters", M101 is estimated to lie at a distance of around 24 million light years from Earth. M101 is most conspicuous for its luminous star forming regions (HII) lying in its outer spiral arms. Many of these regions are so large they have been given their own NGC number. M101 is also famous for its marked asymmetrical appearance that is believed to have been caused by a near collision with another galaxy in its recent (speaking in galactic terms) past. The tidal waves from this near-collision may also be responsible for triggering the strong star formation activity in the spiral arms.
Image Details
| Target: | M101, NGC 5457 |
| Coordinates (Center - J2000): | RA 14h 03m 26s ; Dec +54d 19m 42s |
| Date: | 13 & 14 April 2007 |
| Constellation: | Ursa Major |
| Imaging Location: | Chiefland, Florida |
| Camera: | SBIG ST-8XME & CFW-10 Color Filter Wheel |
| Filters: | Astrodon Series E Tru-Balance LRGB |
| Telescope: | Takahashi TSA-102S 4" APO Triplet f/8 (FL = 814mm) |
| Mount: | Takahashi EM-200 Temma II GEM (12 VDC) |
| Image Scale: | 2.28 arcseconds per pixel |
| CCD Temperature: | -15 C |
| L:R:G:B Exposures: | 90:50:50:50 minutes (10 min. sub-exposures) |
| Mount Control Software: | The Sky 6.0.0.52 |
| Camera Control Software: | CCDSoft 5.00.182 |
| Focus Control Software: | FocusMax 3.3.15 |
| Executive Control Software: | CCD Commander 1.4.5 |
| Sub-frame Registration Software: | Registar |
| Calibration and Combining Software: | CCDStack |
| Final Processing Software: | Photoshop CS |
Additional Information
Description of M101 (By Rob Gendler): http://www.robgendlerastropics.com/M101text.html