Cassiopeia Observatory

Lunar Crater Clavius, Jupiter with Ganymede and Its Shadow

Posted: 9 February 2014

After an extended period of cloudy skies, it was good to be back in the observatory. On my way to the observatory I took this iPhone 5s photo of the western sky shortly after sunset:

Viewed Mercury, 83X, at 1818 MST. A slight crescent was visible through the thin clouds in the west. The view of the crescent phase was better using 222X, although, as expected, seeing was not very good due to the clouds and Mercury's low altitude in the sky.

1822 MST: viewed the waxing gibbous moon, 83X. Then did a terminator tour using 222X. There were some nice details in the crater Clavius, but seeing was not very good. Took this handheld iPhone 5s afocal photo (slightly cropped), 83X:

Beginning at 1841 MST, I did some tests of some new accessories. I will post a review when finished with my testing, hopefully later this month.

1916 MST: Viewed Jupiter, 222X. The moon Ganymede had just ended its transit of the planet and its shadow was beginning to transit. I set up for D7000 DSLR imaging of Jupiter using eyepiece projection at 222X. I first did a focus test using the Bahtinov Mask on the star Betelgeuse. At 1927 MST, I did HD video recordings, 1/30sec, at ISO 1600 and ISO 2000. This image is a stack of 360 frames from the ISO 2000 video using Keith's Image Stacker:

The dark spot on the central meridian is dust on the eyepiece. Ganymede is visible just left of Jupiter, with its shadow near the right limb.

1931 MST: checked on the supernova SN2014j in the M82 galaxy using 83X. The supernova was clearly visible, even with thin clouds and a bright moonlit sky. Back on 23 January, Rob Sparks (Twitter: @halfastro) had posted his photo of supernova SN2014j in M82 on his blog. What intrigued me was that his photo was taken with a 300mm telephoto lens. I decided to try to match his photo using my Nikon D7000 DSLR w/300mm lens piggybacked on the Meade 8" LX200-ACF telescope. Unfortunately, due to the telescope orientation and the weight of the camera lens, the camera kept slipping on the Meade piggyback adapter. I tried several times but finally had to give up due to the clouds. I have had this problem before when using a long lens on the DSLR. I guess I will have to look for an alternative piggyback adapter.

1956 MST: briefly viewed Jupiter and Ganymede's shadow transit, 83X. With clouds increasing in the southern sky (as well as the northern sky), I viewed M42 (Great Nebula in Orion), 83X. I then did some more accessory tests. At 2021 MST, the clouds were now in most of the sky. Took a final look at Jupiter, 83X and 222X. Ganymede's shadow was at the central meridian at 2032 MST.

5 February 2014 was the 5th anniversary of the beginning of construction for Cassiopeia Observatory. Although I wasn't able to observe on the anniversary due to cloudy skies, you can read the very short report of the event on my "Road to Oracle Observatory" blog.

I recently finished reading "Astronomy with an Opera-Glass" by Garrett P. Serviss on my iPad. While many of the astronomical theories mentioned in the book are dated (and wrong), the book was entertaining to read and brought back memories of when I was learning my way around the night sky many decades ago. The book can still be useful to new amateurs (but is somewhat dangerous with the outdated theories). Descriptions of what can viewed using "opera glasses" will be helpful to users of binoculars.

Two sentences in the book really caught my attention: "Always avoid the neighborhood of any bright light. Electric lights in particular are an abomination to star-gazers." And this is from a book published in 1890. Yes, Eighteen Ninety!