Choosing A Telescope
Telescope Aperture Considerations
Introduction to Planetary Sketching
Refractor Dobsonian Style Mounts
The Bonds: Pioneers of American Astronomy
Saturn's Encke Minima and Encke Division
Nature and Travel Photography
Recommended Astronomy Books
Comet 17P Holmes, November 17th, 2007
Comet 17P Holmes, November 17th, 2007, 7:00 - 7:45 UT. Clear skies with the limiting magnitude around 5.4, seeing 5 - 6 (fair - good).
TMB Optical 105mm f/6.2 refractor on an alt-az mount. Magnification 27x-41x, field of view approximately 2.4 degrees.
The comet appeared noticeably larger through this telescope than the last time I observed it, and it is estimated to be larger than the Sun. The inner coma appeared elongated, and the trailing or left-hand side of the outer coma appeared very diffuse or undefined. A faint tail was noticeable and was most prominent along the following upper and lower left-hand side. I used different deep-sky filters including a Baader UHC-S filter to helped bring out the fainter detail in the comet.
Before coming in I noticed that Ursa Major was well up in the northeastern sky, and Arcturus was visible through the trees along the horizon. The Milky Way was visible from Cassiopeia, Perseus, Auriga, and between Orion and Gemini.