Astrofiles
Auburn Astronomical Society E-Newsletter
June, 2007

In this Issue

June Events Upcoming Events
Member News May Star Party
AAS Shirts Observing Primer (cont’d)

June Events

  This month’s meeting will be on Friday, June 1, at 8:00PM in room 215 of the Aerospace Engineering Building.  The parking lot behind the AE building has reopened.  Riders from the Montgomery area are welcome to meet at the home of Russell Whigham, 518 Seminole Dr.,  and carpool over to Auburn.  Plan to be ready to leave for Auburn at 7:00PM. 

Our dark-sky star party this month, will be on Saturday, June 16, at Cliff Hill’s farm, clouds permitting of course. 

Upcoming Events

May 4, May meeting - 8:00PM in room 215 of the Aerospace Engineering Building
May 12, 1st May star party at Cliff Hill’s farm
May 19, 2nd May star party at Cliff Hill’s farm / Sidewalk Astronomy Night? 
June 1, June meeting - 8:00PM in room 215 of the Aerospace Engineering Building
June 16, June star party at Cliff Hill’s farm
July 13, July meeting.  Note date change for the holiday weekend.
July 14, July star party at Cliff Hill’s farm
August 3, August meeting - 8:00PM in room 215 of the Aerospace Engineering Building
August 11, August star party/Perseid meteor shower at Cliff Hill’s farm
September 7, September meeting - 8:00PM in room 215 of the Aerospace Engineering Building
September 8, September star party at Cliff Hill’s farm


Member News

… Got my scope out Saturday night. It was a great night!! Venus has been so gloriously bright,. I didn't know the magnitude . Thanks for saying in your email (-4.2)  It was a beautiful sight to see the Moon and Venus so close together right in my nice dark back yard!!!!! )  I'm so glad I haven't had any more houses build around me yet at the golf course, but it is only a matter of time. Boo Hoo.  I feel sorry for folks that never take the time to go out  at night and glace upward. I'll have to see if I can spot Mercury tonight. with my cat Ozzie and Pete the possum (that likes to hang out at my house at night) 

Take Care. 
Gail Smitherman

May Star Party

On Saturday, May 19, Alan Cook, Everett Leonard, Frank Ward, Don & Kim Cluck, and your editor met under the clear blue skies at Cliff Hill’s farm for a pleasant evening under the stars.  Venus was easy in early twilight just off of the southern cusp of the three-day-old Moon.  Later Frank spotted Mercury which we confirmed by its roiling disk in the telescopes. Still at the eyepiece, we observed the “half-Venus”, and the deep relief views of lunar craters including the unusual Petavius

While we waited for the Moon to set, we had what might be our last decent look at Saturn for several months.  As the sky grew darker, we observed galaxies, nebulae, and star clusters – naked-eye, with binoculars, and with the scopes -- with the giant globular, Omega Centaurii as the pièce de résistance for the evening.

Even in the middle of May, jackets felt good as the air temperature dropped into the low fifties.  As if the evening wasn’t perfect enough, we were entertained by a whip-poor-will, the frogs at Cliff’s pond, and a mocking bird that was still going strong at midnight.

Former AAS member, Bill Prados sent this image of the Moon and Mercury on Friday May 18.
 

I took a picture of Mercury this evening; first time I have seen it this appearance. This is in my back yard in Tyler, TX.

I have a Canon 10D and usually use a 35mm f/2 lens. It happens to focus well when I simply turn the lens to infinity (they don't all do this, which can be frustrating). I use iso 800 and stop down to at least f/2.8 for nighttime pictures to avoid edge distortion, and can get good constellation pics at 6-8 seconds. It has mirror lockup and a cable release.  Since it was dusk, in that Mercury pic it was iso 800, f/5.6, and 1 second exposure.

There is an Astronomy Society of East Texas: http://aset.tamu.edu/ .  I communicate with them by group email. They are a loose group and have no regular star parties. Some folks were getting together Sat nite, but I was on call. I think there is some interest in getting a regular place and time. I hope so because I miss our gatherings in Auburn (and Birmingham). 

See ya later .... Bill

Bill Prados



The following five images are from Scott Thompson:


 
 
 


 



Images from Russell Whigham


This widefield shot shows Venus & the Moon together, with Mercury to the lower right


Venus and the Moon
 

AAS Shirts

We’ve had only four requests for new AAS shirt orders.  We discussed ordering a few to “keep in stock” at the May meeting, to make the order worth Scott Thompson’s time, but no consensus was reached.  If you are interested in having one (or more), let me know and I’ll forward the order to Scott, If you still want to get your order in, we’ll need to know:

  • Men’s or Women's
  • Size,
  • Quantity 
  • With or without your name embroidered.


Observing Primer (cont’d)

Michael Schwartz wrote:

I had a tough time this past Friday trying to resolve any details in Jupiter. I could make out the planet and clearly see it's moons. But I couldn't even  make out any lines on the planet. My C-8 usually does well with 40mm EP. My wife thought that it may have been due to some smoke from the fires in GA and FL. Any thoughts? 


There are several reasons why the image might be soft.  Given the amount of research that you've put into this, I'm sure most, if not all of the following is old news for you, but I'm listing a few possibilities that may explain your poor images:

1.  Internal tube currents.  SCT's have slow cool down times because of the sealed OTA.  Even though I keep it in a cool place in my storage room, my C-11 takes a couple of hours to approach ambient temperature.  You can see if this is the problem by defocusing a bright star and looking for swirling in the "doughnut".  You may also see a heat plume rising from the defocused image toward the top of the tube.  If you put a finger in front of the bottom of the corrector, you'll see how just a small temperature differential as your body heat can reek havoc with the internal seeing.  An active dew suppressor heat strap will actually help stabilize the air inside the tube.  My best seeing has been just before dawn when everything has reached thermal equilibrium.

2. External heat sources.  If you're looking over a roof top or asphalt or concrete surface, it will be giving up heat stored during the day for most of the night.  Looking over a large expanse of water is best and over grass next best, but even then you can have convection issues.

3. Too much atmosphere.  Until your target is about half way up, you're looking sideways through our atmosphere.  Zenith is best.  I think the cool front that came through Friday pushed most of the smoke out of here.

4. Seeing.  Saturday night was not good for Jupiter.  We suspected this when we saw Antares severely shimmering after it was well up above the horizon.

5. Collimation.  Even with the best seeing you won't get crisp planet images until you achieve really good collimation.  You'll need to get to Thierry Legault's third step to have that.  The nights when seeing will permit seeing the diffraction rings around stars are so few around here, that I've never reached this stage, but I keep trying.

Hoping to see everyone at the meeting and star party,

Russell