D7000 Imaging: M57, M13 Spectroscopy, M110, M32, Moon
Posted: 18 October 2011
The observatory was opened at 1813 MST, 84°F. 1818 MST: Venus, nearly at horizon, at 77X through tree branches. 1831 MST: M57 (Ring Nebula), faintly visible at 77X against still bright sky. SYNCed on M57. 1851 MST: good view of M57 now. Began setting up for spectroscopy with the D7000 DSLR and Star Analyser at prime focus of the 8" LX200-ACF. Did Bahtinov Mask focus test on the star Vega, then over to M57 (visible in the camera viewfinder). Captured this 30 second, ISO 6400, unguided, (cropped) image (without the Star Analyser):
I attached the Star Analyser; I could still see M57 in the camera viewfinder but no spectrum of it was visible. This is a 30 second, ISO 6400, unguided, (full frame) image:
The red M57 image is probably a reflection artifact as the spacing from the original object does not match the spacing between stars and their spectra. No spectrum of M57 was visible in the image. But the image does make for an interesting photograph.
I repeated the experiment with M13, the Great Globular Cluster in Hercules. This is a (cropped) 30 second, ISO 6400, unguided exposure, with M13 faintly visible on the left:
Interesting but not very useful.
1917 MST: ended imaging and viewed M13 at 77X. I then paused to watch a low ISS pass that began at 1924 MST. The pass was low in the sky, skimming the tops of the trees from the west through north. 1930 MST: returned to the telescope and began a "Tonight's Best" AutoStar Guided Tour using the 26mm (77X) eyepiece. Viewed the Double Cluster, Albireo (nice double star), M7 (open cluster), M22 (globular cluster), M34 (open cluster), M8 (Lagoon Nebula), M15 (globular cluster), M27 (Dumbbell Nebula), M2 (globular cluster), M20 (Trifid Nebula), M17 (Swan Nebula), M92 (globular cluster), M11 (Wild Duck Cluster; where's the "duck"?), M31 (Andromeda Galaxy), M52 (open cluster), Uranus, Neptune, and Jupiter. 2004 MST: ended the tour.
Returned to M27 (Dumbbell Nebula) for some detailed observing. Tried the OIII and Hydrogen-Beta filters on it at 77X. Using the OIII filter, I could see more structure in the fainter areas of the nebula. With the Hβ filter there was no improvement. Tried the Hβ filter on M57 (Ring Nebula), again no improvement. Using the OIII filter on M57, the view was improved by increasing the contrast of the ring with the background sky, and there was an "electric" look to the ring. Then went to M31 (Andromeda Galaxy). The nucleus of the galaxy appeared more distinct with the OIII filter, but the dark lanes in the spiral arms that were visible without the filter were not visible with the filter. The Hβ filter was no help.
I then did some extended observing of M110 (companion galaxy to M31). The view was good at 77X. I decided to image M110. SYNCed on it, did a focus test with the Bahtinov Mask on the star Alpha Andromeda, and returned to M110 for a framing test exposure. The galaxy was too faint to be seen in the camera viewfinder. I then captured this 2 minute, ISO 6400, unguided, exposure of M110:
I also captured M32 (another M31 companion galaxy), 2 minutes, ISO 6400, unguided:
2058 MST: ended imaging. At 2111 MST, I began observing Jupiter. At 77X, three moons were visible. Switched to the 9.7mm eyepiece (206X) plus moon filter. The view was awesome with lots of details visible. I noticed that a moon's shadow was making "3rd contact". I monitored it through "4th contact". Using the "Jupiter's Moons" tool at the Sky and Telescope web site with my iPhone 4, I learned that the shadow was from the moon Europa and that the moon itself was transiting the Jovian disk. Initially I could not see the moon against the bright Jovian disk, but perseverance paid off and at 2131 MST I finally saw Europa. I continued observing Europa until the transit ended at 2148 MST. Seeing Europa was made easier by the fact that it appeared over the South Temperate Belt, which provided a darker background. Europa appeared as a bright "star" on Jupiter's disk. As it approached the Jovian limb, it became easier and easier to see due to limb darkening.
2150 MST: the eastern sky was brightening from the rising waning moon. 2232 MST: the moon appeared over the hill to the east of the observatory. 2246 MST: with the moon still low in the sky, did some lunar observing at 77X. 2300 MST: switched to the 15mm eyepiece (133X); some nice views of the moon, even though still low in the sky. 2306 MST: switched to the 9.7mm eyepiece (206X). There was surprisingly good seeing. 2315 MST: began setting up for prime focus + visual back D7000 imaging. 2319 MST: took this 1/320sec, ISO 400, exposure:
2326 MST: took a final look at the moon at 77X and then Jupiter.
Closed the observatory at 2338 MST, 69°F.
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