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Auburn Astronomical Society E-Newsletter July, 2007 In this Issue
Our dark-sky star party this month, will be on Saturday, July 14, at Cliff Hill’s farm, clouds permitting of course. July 13, July meeting From: Scott Thompson
Clouds now and again give a soul some respite
from stargazing, but this year there have been far too few rain clouds,
and lake water levels continue to drop. Water is a precious resource and
we sometimes forget this fact because it is so readily available to us.
Count yourself lucky; 1.1 billion people lack access to an improved water
supply.
Seventy percent of the earth is covered with water, mostly in the oceans. Water also exists in the air as water vapor and in the soil as groundwater. So just what is the total water supply of the world? The Department of the Interior, Geological Survey states that it is 332.5 million cubic miles, or 1.386 million cubic kilometers of water. One cubic mile equals 1.1 trillion gallons of water. So you are probably thinking, that’s a lot of water and we don’t have anything to worry about. Well, the old saying, Water, water everywhere but not a drop to drink is very appropriate since only 2.5% of the Earth's water is fresh (not salty) and most of that percent is locked up in the glaciers, air or ground. Think of it this way. If all the earth’s water fit in a gallon jug, available fresh water would equal just over a tablespoon. So out of the total about .014% is the readily accessible water found in lakes, streams and rivers. This is “small potatoes” compared to the total. What about water on other planets, moons, and even the sun? There is evidence that water resides elsewhere in our solar system. Our nearest neighbor, the moon, may contain water. In 1994, the Clementine spacecraft mapped the moon’s surface and detected reflections that seemed to come from icy material. Then, in 1998, a signal from the polar craters checked by the Lunar Prospector indicated hydrogen, possibly as the H in H2O. However, all this seems inconclusive. So watch for a new spacecraft in 2008 called the Lunar Reconnaissance Orbiter (LRO) featuring many advanced sensors that can sense water in at least four different ways. Mars has water and scientist think in large amounts. Where it is located and how to get to it are two topics still under debate. With water on Mars, we humans would have the ability to grow food, create and store energy, and protect ourselves from radiation if we should decide to take up residence. Next year NASA plans some promising missions to Mars to study water near the planet’s North Pole. The upcoming Phoenix mission has two goals. One is to study the geologic history of water, the key to unlocking the story of past climate change. The other is to search for evidence of a habitable zone that may exist in the ice-soil boundary, the "biological paydirt", as they call it on their website http://www.nasa.gov. Europa, the moon of Jupiter, may contain an ocean of water. Enceladus, a moon of Saturn, shows stripes or fissures that appear to be the source of H2O vapor geysers. The latter evidence came from observations by the Cassini spacecraft. Pluto’s composition is unknown but many think it could be made up of 10 percent H2O ice. There are many more planets and moons that we could list, but what about our sun? It has been discovered that water exists on the
surface of the sun in sunspots. These sunspots are cooler regions on the
sun, where it has been proven that water exists in a non-liquid form. The
sun is, of course, too hot for the water to be liquid but not for water
vapor or steam. This water plays a part in the greenhouse effect
that occurs within the sunspots.
On July 16th look for the crescent Moon, Saturn, Venus and the star Regulus. Regulus and Venus will be two and a half degrees apart. Venus will be at its greatest brilliancy on July
12th. We will have a new moon on the 14th and on the 16th the moon will
be a thin crescent just above the horizon. The earth will be at its farthest
point from the sun this year around 7p.m. on July 6th.
July's and past issues of Under the Stars articles
are online (with images):
From: Michael Schwartz <askchefmichael@yahoo.com>
Well, I finally started the process of EP upgrades. I received the Denk Power Switch 2X diagonal, Nagler 11mm, and a wide angle 31mm made by Proxima. I've only given them a test run under the city
light glare so far. Hopefully, I'll be able to make the Star party for
July. I'd like to see how these new additions will do under darker conditions.
Maybe we can put them onto someones larger scope ( vs. my C-8 ) and see
what they can really do. I'm still in the mind to purchase a large ap.
Dob sometime in the future. The more I read about the Meade Light-bridge
16 , the more I'm inclined to get one. Here's my Q of the month
Talk to you soon- Chef
From: Syd Spain
Barnard Observatory Frederick
Augustus Porter Barnard was the University's first chancellor.
In 1856, Barnard, the former Chair of Physics and Astronomy convinced the
Legislature to appropriate funds to order the largest telescope in the
world for the University and to construct an observatory for it on campus.
The large telescope that Barnard had dreamed of was ordered from Alvan
Clark & Sons in 1857. In January, 1862, when Alvan Clark was
testing the telescope he discovered
Sirius B, the "white dwarf" companion of Sirius the "dog star.” However,
due to the outbreak of the Civil War, the telescope was never delivered
to the University of Mississippi. Barnard's telescope was subsequently
purchased by the Chicago Astronomical Society in 1863, and was given in
trust to Northwestern University in 1887. That telescope, together
with Barnard's
collection of physics instruments, would have allowed the University
of Mississippi to become the foremost institution in America for the study
of physics and astronomy. One of only three remaining antebellum
buildings on campus, the Barnard
Observatory is now the home of the Center
for the Study of Southern Culture.
The main entrance of the observatory, faces due south, and the building is precisely aligned east to west. A small tube in the south wall is oriented such that direct rays of the sun shine through it to the floor only twice a year, at noon on the vernal and autumnal equinoxes. The slanted metal roof of the transit room (between the main and small rooms) was designed to open for observations using a three inch meridian telescope. In 1997 the smaller dome and the octagonal rooms
of the Kennon Observatory were refurbished. The smaller dome currently
houses an electronic CCD camera attached to a twelve inch Schmidt-Cassegrian
telescope.
• A 25-inch Obsession
reflector
Kennon Observatory 2007
Astronomy Open House Each month on Friday, nearest the date of the first quarter moon, the University has an open house for community residents and visitors to view planets, stars, and constellations. Three mounted wedges which have power outlets are arranged around the Kennon Observatory. Note the mounted wedges shown in the second and third photos above. I attended on June 22, 2007 from 8:30 PM until midnight. Astronomy faculty members and several student assistants answered questions and helped between 75 and 100 visitors enjoy views of the night sky. The main dome of the observatory was open, and the 15 inch Grubb refractor focused on the moon. It’s an awesome telescope which doesn’t show its age of more than 110 years. It’s equipped with tracking motor drives, but the original tracking gear system is kept in an adjacent room. The gear mechanism was attached to suspended weights to enable easier moves of the large telescope. Two telescopes were mounted on the wedges. One was a 12 inch Meade LX200 which tracked Venus until it descended behind a campus building. It then was skewed to various stars and planets based upon requests from the attendees. An 8 inch wedge mounted Celestron SCT tracked Jupiter, and a 70 mm tripod mounted Televue was moved to a variety of visual destinations. The Astronomy Laboratory was open, and the 25 inch Obsession dobsonian dominated the lab. It has large wheels and is moved outside when there is an unusual astronomical event. A number of computers were operating in the lab. They illustrated astronomical photographs taken faculty and students as well as astronomy information. I was surprised that there is no astronomy club in Oxford. The nearest ones are in French Camp and Memphis. If you plan to be in Oxford about the time of the first quarter moon, then you should visit the University’s web site and search for the public announcement of the open house. If you are unable to locate it, just contact me at sydspain@olemiss.edu. I’ll be happy to find it and send it to you. Come and visit when you can! From: David McConnell
I wondered if you might have any ideas in this problem I'm experiencing. C.C. to Meade: Dear sirs
From: Raul San Miguel, CTR USAR
Please allow me to introduce myself. My name is
Raul. I am located just outside of Ft. Rucker, in Daleville, AL.
I have recently purchased an 8" Orion XT8 Dobsonian mounted reflector telescope.
The AAS website mentioned a star party before
each new moon. If there is
Thank you, Raul San Miguel
Hello Raul, Everyone
is pretty much on a first name basis here, so, please just call me Russell.
We'll be glad to help in any way we can. We look forward to seeing you at the meetings and/or star parties. I know it's a long drive, so just come when you can. I don't know if you're familiar with Alabama weather, but the high temperature and humidity during the summer months really take a toll on transparency, making going to a dark-sky site almost futile until late September. I'll be out of town this weekend, but if you want to drive up to our dark-sky site, you'll be welcomed. From the AAS home page, select "Star Party" and Cliff Hill's farm. for directions. About five years ago, the was a "Wiregrass Astronomical Society". They had a few star parties with 6 or 8 folks, but the fellow who organized the effort, moved to New Orleans, and I think the group fell apart. There's still a "wiregrassastronomy" group, but it too is now moribund. You might try posting something there and see if you get any responses. For the past several years it's been only spam, but I've kept it subscribed in hopes that someone down there would breath new life into the group. Go back to the 2002 messages to see if any of the e-mail addresses are still good. You may also check with the folks at Landmark Park. Well, I found the farm easy enough, but I got mighty lonely. Seems that I missed the cancellation memo I checked out Venus, Jupiter, Saturn and even
had a go at the new moon. Seeing was poor and the clouds sent me
home early.
Next time I think I will ask for a contact phone# to ensure I won't be stuck out there alone. Do you have any member here in my area? Anyone
willing to show me the
Maybe next time. Thank you, Raul San Miguel Hello
Raul,
Well, I found the farm easy enough, but I got mighty lonely. Seems that I missed the cancellation memo :) Yikes! I'm sorry you drove all that way only to be "stood up". I checked out Venus, Jupiter, Saturn and even
had a go at the new moon.
Maybe that's why you had it by yourself. If it was that bad, most folks can see the objects you mentioned from their own light-polluted backyards. For what it's worth, star party attendance probably will not improve until late September when we once again have dry transparent skies. Well, that and the eerie 1970's horror B-movie soundtrack performed by the local insects, fowl, dogs, horses and a donkey (I think) You were just on the wrong track. You should have changed your player to the "Frogs croaking, Whip-poor-will's mournful trill, and Crickets chirping Symphony" track, with the Fireflies and the Milky-Way providing the light show. The good news is, that the donkey keeps the coyotes away! Next time I think I will ask for a contact phone# to ensure I won't be stuck out there alone. You may have a hard time placing that bell around the cat's neck. It turns out that I'm the world's worst weather guesser. So, usually you should do the opposite of what I recommend. Seriously, check the "Transparency" metric on the Sky Clock (on the "Star Party/Cliff Hill's Farm link). If it's lighter that medium to dark blue, it will probably be a pretty lonely star party. Do you have any member here in my area? Anyone willing to show me the ropes? I'm afraid not. You seem to be the most experienced person on our mail list from the Wiregrass. BTW, I saw your message on the Yahoo!groups list, but no replies. Stay in touch, Russell From: Heather Sherbourne
Dear Dr. Jenkins,From: Rhon Jenkins" Subject: Re: Astro Club Info Ms. Sherbourne,
Hello Heather,From: Heather Sherbourne To: Russell Whigham Subject: Re: Welcome to the Auburn Astronomical Society Thanks for adding me to your list. I'm really looking forward to meeting you and the rest of the club members. And, I'm thrilled to hear that there are a few that live somewhat close to me. I'm shooting to be at the meeting in July. Hope to see you then. We now have six (members only) requests for new
AAS shirt orders:
Scott Thompson has offered to get prices when we’ve heard from all who wish to order. This is the final call. If you are interested in having one (or more), let me know and I’ll forward the order to Scott, If you want to get your order in, we’ll need to know:
Just to bring everyone up to date, here’s a brief recap of the project: When Ray Kunert learned that AAS had a 12.5-inch, f/7 Cave Astrola telescope languishing in storage, he started a campaign to resurrect the beast and get it back into service. Last July, we made arrangements to pick up the scope that had been at Jim Chestnut’s house for the previous twenty years. [See the AAS History page, for the years 1983-1988]. As we have no observatory to keep it permanently mounted, and given that the massive german equatorial mount precludes it from being easily moved, a decision was made to mount the original tube assembly on a Dobsonian mount and that it be used as a loaner scope. Ray has since reconditioned the hardware and done an excellent job of putting a new finish on the tube. The primary mirror was in pretty good shape, but the secondary needed to be realuminized. William Baugh volunteered to take care of that for us. At last month’s (June) meeting, William returned the newly aluminized diagonal. A big “Thank you!” to William for doing that for us. Meanwhile, we had contacted our resident telescope maker, Tom McGowan, about making a rocker box. Tom called the Sunday following our June meeting and said that he would have time to work on the rocker box during the next few weeks. Tom said that he would need the optics in the tube for balancing. He recommended a Telrad rather than a finder scope. He'll see if we can incorporate the rotating rings into the mount. The rings aren’t really necessary with the Dobsonian configuration, but Tom determined that using them as a saddle would be the easiest way to mate the tube assembly to the rocker box. Tom offered a couple of options for the rocker box:
Later that same Sunday afternoon, I met Ray at his house with diagonal in hand. Ray already had the 12.5-inch tube assembly loaded up in his van. We delivered it to Tom and discussed his proposals. We need to be thinking about a an eyepiece (or 2). I think we need something better than the 2-inch 32 Kellner (I think) that came with the scope. Tom mentioned a couple of Pan-Optics, but we need to keep in mind that this will be a loaner. John Zachry reports $756.91 in the treasury. We can discuss this at this month’s meeting. When I mentioned to Tom about his expenses, he said he had some left-over plywood and hardware and generously offered to donate the materials and his time. When Tom made that offer, I think he had under-estimated how much wood that would be. We'll certainly want to cover Tom's expenses, and an expression of thanks to Tom and "Midnightelescopes", somewhere on the box would be nice. Thanks Tom! We'll also need to decide on where to keep the scope when it's finished. One possibility would be to keep it at the W. A. Gayle Planetarium when not loaned out. Rick Evans has a small scope at the entrance to the planetarium now. If we could put this one there, perhaps with "Auburn Astronomical Society" and "www.auburnastro.org" nicely lettered on the tube, it would provide some excellent publicity. This would also make a wonderful addition for our annual Astronomy Day events, there. Rick has welcomed the idea, and offered to “accommodate you in any way we can. Just let me know”. Tom has warned that the finished product will be quite large. It will require a good size van or pick-up truck as well as two people to transport and use, but should provide magnicifant images. Here's an interesting virtual tour of Canon's lens plant from the raw materials to the finished product (a 500mm lens). The same or similar techniques are no doubt used on refractors and eyepieces. <http://www.canon.com/camera-museum/tech/l_plant/index.html> From: Larry Owsley
http://www.space.com/scienceastronomy/060303_big_crater.html From: Dennis Persyk sct-user yahoogroups.com
Afocal: Camera lens is attached and camera focuses on virtual image of the eyepiece. Eyepiece projection: Camera lens is off and eyepiece serves as its lens and projects the real image onto the film/chip plane. Here are some nice ray diagrams illustrating the
various imaging modes:
ISS transiting the Sun Image
Hoping to see everyone at the meeting, Russell
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