Discussion of business items this month included a few comments on our last winter star party, discussion about having a vinyl sign made to use at club events and a reminder that Astronomy Day will be Saturday, May 7. After the business meeting, Steve Plank gave a brief demo of his new Vixen telescope, followed by an update on recent astronomical news by Joyce Gray-Ritchie. This month's program, titled "Ken Willcox: The Birth of an Eclipse Chaser", was presented by Daryl Doughty.
Vixen Telescope Demonstration - Steve Plank
After the business meeting, Steve Plank gave a brief show and tell about his new Vixen VMC110L telescope <http://www.opticsplanet.net/vixen-vmc110l-optical-tube-assembly-w-porta-ii-mount.html> . The scope is a Maksutov-Cassegrain design with a 4.3" aperture and an f/9.4 focal ratio. Since this design inserts a small corrector lens just in front of the secondary mirror, rather than using a full aperture corrector plate like Schmidt-Cassegrains, the end of the tube is open, allowing free air movement and therefore, quick cool down. With mostly metal construction, the VMC110L is very solid and stable for a grab and go scope. The Maksutov flip mirror design provides two eyepiece ports; a straight through and a right angle on the top of the tube at the back, making it particularly convenient for photography. Sturdy, curved spider vanes support the secondary while minimizing diffraction spikes, and a red dot finder is included with the scope. The alt/az mount's convenient slow motion controls provide precise positioning. This scope gave very good views of Jupiter and deep sky objects at our Winter Star Party, and it's silky smooth focusing system was a joy to use.
What's News - Joyce Gray-Ritchie
Exciting things have been happening in astronomy lately, and Joyce updated the club on some significant recent news items.
In the past, Mars was considered a dead world with very little change taking place. But recent discoveries on high resolution photos from Mars Reconnaissance Orbiter and Mars Express have clearly demonstrated that Mars is a dynamic world with constantly changing geologic features. Most of the changes seen are caused by sand and ice cascading down sand dune slip faces. Recent analysis of high resolution images has identified spring sublimation of a layer of frozen winter carbon dioxide, along with stronger than expected wind gusts, for triggering sand avalanches. Researchers say they have seen about 40 percent of far northern sites exhibit changes over the two year (Martian year) study.
Over the past two decades, nearly 500 exoplanets have been discovered by ground based observations with large telescopes. During the past two years, the Kepler planet hunting telescope, which is in an Earth trailing solar orbit, has been staring continuously at a small region of the sky in the constellation Cygnus. It monitors nearly 145,000 stars in the region for minute brightness changes that could indicate the transit of a planet across the disk of the star. NASA astronomers announced on February 2 that, based on only four months of data, Kepler has identified 1235 candidate planets. Of these, 54 may be in the habitable zone of their star (where liquid water could exist), 68 are about the size of the Earth, and five of those Earth size planets orbit within their stars habitable zone. The results suggest that planets are very common among the stars in our galaxy and that Earth size planets are a higher proportion of exoplanets than previously believed. This, of course, may carry significant implications for the possibility of life elsewhere in our galaxy.
There is a citizen scientist project associated with the Kepler mission that allows anyone with access to the internet to participate in exoplanet discovery by evaluating light curves from Kepler for transit events. You can get involved at <http://www.planethunters.org/> .
Ken Willcox: The Birth of an Eclipse Chaser - Daryl Doughty
Among countless other accomplishments, Ken Willcox organized and led five major total solar eclipse expeditions (Hawaii 1991, Bolivia 1994, India 1995, Mongolia 1997 and Aruba 1998), co-authored two editions of the book TOTALITY: Eclipses of the Sun with Mark Littman, and founded the Southern Skies Star Party in Bolivia after his eclipse trip there. But his involvement with solar eclipses began when he and Daryl made a trip north, into Canada, to view a total solar eclipse near Gladstone, Manitoba, in February 1979. During our program this month, Daryl described details of their adventure and displayed some of the resulting eclipse photographs.
Ken, Bill, Daryl, Ottawa doctor
Despite Ken's attention to detail, the expedition was not without its surprises. No amount of preparation could eliminate the threat that uncooperative weather could completely hide the event, but last minute hunches, based on the most recent forecasts led them to Gladstone, Manitoba, near the centerline of totality. Despite the disappointingly hazy skies while traveling to their site on the morning of the eclipse, conditions had improved by the time of first contact. Daryl captured a multi-exposure photo sequence of the eclipse from beginning to end using a tripod mounted camera, while Ken captured a series of individual photos using his Celestron C8 and a partial aperture solar filter. Later, on inspecting his photos, Ken discovered another unexpected detail. Removing his solar filter to photograph prominences and the solar corona during totality had slightly changed the optical path, leaving all of his totality photos a bit out of focus.
But the program wasn't just about an eclipse; it was also about a friendship. Daryl's and Ken's paths crossed while working for the National Institute for Petroleum and Energy Research in the late 60's. They soon discovered their mutual interest in astronomy and developed a strong friendship. Although, career and education decisions sent them in different directions, they both eventually returned to Bartlesville and renewed their friendship and their astronomical collaborations. It was 20 years, to the day, after the eclipse in Gladstone, that Ken died. Daryl's program reminded those of us who knew Ken to revisit our memories of him and the value of his friendship.
Totality by Ken Willcox
Monday, March 7, Rick Bryant will present "The Cheapskate Astronomer’s Introduction to Astrophotography, Part II: Help! The Gremlins are Attacking", in the Bartlesville Public Library Meeting Room. For more information, see the meeting announcement on our website home page at <http://sites.google.com/site/bartlesvilleastronomyclub/> .
BAS Public Website: http://sites.google.com/site/bartlesvilleastronomyclub/
BAS Yahoo Group: http://tech.groups.yahoo.com/group/BvilleAstro/
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