We hosted our September Open Night as scheduled on the 30th with Earth’s Moon as our primary subject. The sky was (for once) completely clear of clouds and full of stars when we opened the dome for the 9:00 start. In all, 19 folks from small children to senior citizens attended and enjoyed spectacular views of our nearest neighbor in space. Two or three individuals attempted smart phone photography of the Moon with varying degrees of success. We also observed the Andromeda Galaxy and the Perseus Double Cluster. The image above was made just before we closed up and has been corrected for the telescope’s optical “flipping” of the image. Camera used was a Canon EOS 7D equipped with a 50mm lens and held to the telescope’s massive eyepiece. We will look at the Moon again October 28 when we celebrate the annual International Observe the Moon Night. See you then?
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We hosted a small group of 16 visitors during the July 16 Open Night but enjoyed the event very much; a group of that size is in the not-too-large and not-too-small range that affords easy conversation and sharing of the observatory experience. I the summertime we usually feature Earth’s Moon. Between summer’s late sunsets, and Daylight Saving Time extending twilight by an hour, the Moon reliably shows up even before the sky is dark! Saturday’s experience was no exception.
We viewed the Moon through the Cooley Telescope’s remarkable optics and were rewarded with exciting detail. Moving along as the sky darkened, we turned our attention to Saturn: the planet’s subtle color and distinctive ring system showed good detail, very good at times. We briefly viewed Mars but the Red Planet is rapidly parting company with Earth and has grown small in the telescope’s eyepiece.
Yes, the “star” of the night was Luna and, once the last visitors departed, we made a few images of our nearest neighbor in space to help illustrate why we love sharing the view!
Preparing for this week’s expected heavy rains and wind, I went to the roof of the observatory to clean out the rain gutters and check the downspouts. Chores done and with the dome open, I made another experiment at solar imaging through the big vintage Cooley Telescope. I found I could focus on the Sun (through a safe solar filter) and, with a Canon DSLR camera at the telescope’s prime focus, recorded a few one-shot images at ISO 400 and 1/500 second. The telescope is a 9-inch refractor with a focal length of 3,327mm. The results appear better than last time but show the apparent effect of atmospheric turbulence: that’s my story and I’m sticking with it! A few sunspots were visible and details of Sol’s roiling atmosphere show up. The photographic technique is the simplest we can use; more sophisticated processes are employed these days to achieve best results. Still, proof of concept is a good thing and getting the image focused is a critical step. I think next time we may try a dimmer subject.
NOTES: Sunspots in this image are #2387 (L) and #2386 (R). For more information on the Sun’s photosphere and what can be seen there, visit this page at NASA/ Marshall Space Flight Center.
Our Sun is just past the peak of its 11-year activity cycle but has been unusually quiet of late. Many days we have seen few, if any, sunspots marking the star’s face. Over the past few days, however, there has been an uptick in activity including the passage of large sunspot region AR2339 (lower-right in our photo). The sunspot has been the source of major solar flares including one that interfered with radio communications in the Pacific region. This image is a single exposure made using a digital SLR camera held to the eyepiece of the Cooley Telescope at Stephens Memorial Observatory. A white-light filter was used for the protection of equipment and vision. A good article on the current solar cycle can be found here.