RichmondAstronomical Society
746th Consecutive Meeting
November 8, 2011
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Jim Browder called our meeting to order in theEurekaroom.
Greeting & Announcements – approximately 37 in attendance at the meeting.
Please check the link to our RAS blog: http://richastro.org/index.php/category/blog/
Annual dues are due.
$30 for a regular membership; $10 more to be an observatory operator.
Benefit of being a member is you are eligible for a discount subscription to Sky & Telescope and Astronomy. You can pay by check to Jim Blowers or by PayPal at this link: http://richastro.org/ras_payments.htm
If you joined our organization after July 1, your dues payment will be applied to next year.
Election of 2012 Board of Directors was held after asking for nominations from the floor. Chris McCann supervised the election by acclamation. Elected members are:
Jim Blowers, Jim Browder, Gary Cowardin, Chris McCann, David P. Medici, Bill Newman, Prashant Reddy, Tim Streagle, David Walton, Betty Wilson, Ken Wilson
The 2011 Board members were thanked, including the 3 who were stepping down: Cal Pletcher, Bill Jeffries, and Jeff Pike.
Share table:
There were several books on display. “The Big Book of the Universe”, donated books, and library books (to be discussed in a later report). There were also several photos taken at recent star parties and observations.
Library Report was given byVirginia. All is good at the library. Her topic for this month was Sunspots. She brought in a set of related books, including “Our Sun”, “Our Turbulent Sun”, “Chasing the Shadow”, “Sun and Its Influences”, and an old book, “Birth and Death of the Sun”.
Two (2) books have been donated to RAS. Randy Tatum donated a book named “Sleep Walkers”. Jim Calpin donated “First Light”.
Events and Individual Observing
Recent Events:
- Chiefland Floridastar parties (see Frank Green’s blog entry dated 10/30/2011, http://richastro.org/index.php/category/blog/ ) – passage from his blog: The sky is darker at Chiefland than at manyVirginia sites, though not as dark as some of the W.V. ones. However, Chiefland is best known for great seeing. … in a high-power eyepiece — Jupiter was nothing but bands, swirls and eddies from pole to pole, Europa was a beautiful, sharp white orb with a sharp black shadow as it moved across the planet that night. … Some folks had their scopes up to 1,100 power with razor sharp views. Have never experienced seeing like that in Virginia (or anywhere else).
- Girl Scout Astronomy Badge – 2 troops of 6 girls each, Mark and Syndey Mabry helped us out here
- City Point – no one
- Woodlake – 30 observers, helped by Hank and John Raymond
- Byrd Elementary – Tim Streagle and Jim Browder reported that they had a small group of students show up.
- RAS observing at the scout camp – good skies, especially Thursday and Friday; a little cloudy on Saturday; good crowd; had 7 different telescopes available at different times during the night.
Individual observing
Alan saw spectacular views of Jupiter fromPettigrewState Parkin NC. It is a dark sky area located about 3 hours from Eddington, towards Outer Banks.
Upcoming Events:
Thanks to ALL who helped at the skywatches during 2011!!
•ScienceMuseumSkywatch: No skywatch in November! The next skywatch at theScienceMuseumwill be on December 16.
• Heart of Virginia Fall Star Party, November 18 — 20: Star party hosted by the Heart of Virginia Scout Reservation, open to the public, convenient location, nice facilities and a dark sky:
More info at http://bradysaunders net/cam p/starparty.html
Don’t miss it — this should be a great event! The festivities start at 4:00 PM on Friday, November 18 with an astronomy club social.
• Matoaca Middle School Star Party, November 10: Please contact Jim Browder at presidentrichastro.org if you are interested in bringing a scope to his event.
• RAS Board meeting, November 14: 7:00 PM, Extra Billy’s Restaurant onBroad St. Please arrive earlier if you plan to eat.
• Skywatch at Five Forks,Hopewell, November 19: 6:00 PM, contact John Raymond at raymond7419@verizon.net for more information if you are interested in attending.
• Cub Scout Event inEastern Henrico: No date yet specified for this event, please contact Jim Browder at president@richastro.org if you are interested in helping a cub scout troop learn about astronomy and earn their belt loop award.
• December RAS pot luck party – location TBA.
Visitor and New Member Welcome, Chris McCann
We had a few returning visitors, but had 1 new visitor: Tamara Hubbard
Short Talk: “Moons of Jupiter — Research Project,” Nick Annichiarico
Nick is aUniversityofRichmondstudent, studying under Henry Nebel. Nick is researching the orbital periods of the 4 major moons of Jupiter. Using photography, he hopes to repeat what Galileo observed (while under house arrest). His goal is to select 1 of the moons at a time, starting with the closest to Jupiter, track its orbit and calculate its orbital period. As each moon is successfully tracked, Nick will proceed to the next moon and repeat the process again.
Good luck to your studies and research!!
Break
Presentation: “Unusual Refractor Telescopes,” Ken Wilson
Ken presented a lot of information about the historical progression of refractor telescopes, including a few unusual designs. We started off thinking about Galileo’s gear from 1609 – 21x magnification, 37 mm objective diameter, giving a very narrow field of view that covered ¼ of a full moon. Of course, it had its problems, like severe chromatic aberration.
We moved onto Aerial telescopes. In 1673, Johannes Hevelius used a 149-foot long scope that hung from a 90-foot pole. Too easy to move and not stable. Constantine Huygens worked with a 123-foot long scope that was attached to a hinge at the opposite end. The position of the eyepiece was controlled by a cord.
Improvement in refractor lens was proposed by Romer in 1675, when he suggested cutting a lens into 2 halves. The 2 halves were to be moved back and forth to make small measurements. The idea wasn’t successful until John Dolland worked with the concept in 1754.
Much later in history, a “fly’s eye telescope” was developed and used by universities such asHawaiiandArizona. It involved multiple mirrors sending images to a common focus. The same set-up was used to measure the distance to the Moon by reflecting a laser off of instruments left on the Moon by astronauts.
The largest refractor was the Great Paris Refractor, used in 1900. It was a horizontal telescope with a movable mirror at the end. 49.2 inch diameter and a focal length of 187 feet.
Coude created a telescope with a ‘fixed eyepiece’. Most of the telescope was not movable except for a mirror at the end. Most of the telescope was contained inside of a building or structure and was not affected by heat differences.
Unusual mounts:
Peltier’s Merry-go-Round mount, where the telescope rotated about a fixed eyepiece.
‘Auto-mated’ telescope, mounted on the top of a car. It could be moved to wherever it needed to be and could be pointed into any direction. It was also called the “Volvo mount”.
Ken presented a lot of information by use of diagrams, showing quite a lot of ideas to improve telescopes. Very interesting!!
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Reminders:
The next RAS meeting will be Tuesday, December 13th at the SMV.
The next board meeting will be Monday, November 21 at Extra Billy’s at 7:00 PM (arrive earlier for dinner). Meeting is open to all members.
Check out the web site at http://www.richastro.org/
RAS Café Press store. Please take a look at the online store where you can purchase items embossed with the RAS label. The site can be found at http://www.cafepress.com/RichAstroShop .