VOL 34 NO 5 May 2005 PUBLISHED MONTHLY

Star Party at Orion Acres: Saturday, June 4th. Camping is fine if you wish to spend the night. All Star Parties are weather dependent, and subject to cancellation due to clouds or rain. For more information or for confirmation the event is a go in the event of questionable weather, call Victor Rogers at (423) 842-5595. See the BAS website for directions to Orion Acres or visit www.orionacres.org  

MEETING NOTICE:

The regular meeting of the BARNARD ASTRONOMICAL SOCIETY will be held Thursday May 12th at 7:30 PM at Jones Observatory on Brainerd Rd.

PROGRAM:

To be announced.

OFFICERS

APRIL MINUTES

The monthly meeting of The Barnard Astronomical Society, held at the Observatory, The University of The South, Sewanee, TN, was called to order at 7:50 PM on April 14, 2005. Tom Adkins presided over the brief business meeting, and Dr. Douglas Durig of the Physics and Astronomy Dept. presented the program. There were seven BAS members and three Astronomy staff persons from the university present. 

Treasurer's Report: David Witt discussed the advantages for his treasurer functions of obtaining a credit card in the name of BAS. This would expedite transactions with vendors (e.g. astronomy magazines with whom discount subscriptions are arranged for BAS members). This will be discussed further at upcoming BAS meetings before any action is taken.

Old Business: Sam Delay, Jr. has made three presentations on astronomy to student groups which count for credit to keep BAS qualified as a participating club in the NASA Night Sky Network.

Sam Delay, Sr. has been hospitalized recently for treatment of injuries received in several accidental falls. He might appreciate receiving cards or a visit.

New Business: 

The nominating committee (David Witt, Chairman; George Bell; Jim Lauck) presented a 2005 slate of officers for discussion and vote at a subsequent BAS meeting; 

In addition, one new position is being created. 

This formalizes the job that Bill has been doing over the last six months on the BAS membership rolls and astronomy library books. Future BAS databases are already being planned for such categories as BAS owned equipment, member owned equipment and areas of interest, regularly scheduled star-parties in the U.S., recommended vendors, internet Astronomy sites, etc. 

Also, discussions are underway (but no action has yet been taken) concerning three other possible new positions. 

Program: 

Prior to moving into The University of The South Astronomy Laboratory for Dr. Durig's presentation, BAS members had the opportunity to inspect the centerpiece of the Observatory, the six inch Clark refractor telescope, beautifully restored in its brass housing by Francis Cordell. Since Francis could not be present for the meeting, Victor Rogers and Steve Ramey made some minor adjustments and repairs to the non-functioning manual declination controls. This enabled BAS members later in the evening to view along the terminator line of the first quarter moon using the Clark telescope. 

As Dr. Durig began his program in the laboratory, numerous computer screens glowed with charge coupled device detector (ccd) images and data tables showing details of his current research interest-discovering new asteroids and comets. Dr. Durig explained how powerful new computer software now enables universities which do not have extremely large telescopes to merge (overlay) ccd time exposures and resolve objects several hundredths of an arc second apart and detect objects fainter than 21st magnitude in brightness. This is amazing performance, considering that most of his research instruments seem to be Schmidt-Cassegrain Telescopes (SCT's) of 12-14 inch aperture. Dr. Durig pointed out for BAS members distant asteroids and comets among the star backgrounds in his images. He even indicated a gamma ray burst. (Note: this is an entirely separate subject, one which has had the field of astrophysics in turmoil for the last five years as these extremely powerful energy sources out to 10 billion light years distant have seemed to be in violation of basic laws of physics. Dr. Durig will present a program on gamma ray bursts this summer at Sewanee.). The clearinghouse for new discoveries of asteroids and comets is The Minor Planet Center, at the Harvard-Smithsonian Center for Astrophysics, located in Cambridge, MA; and affiliated with the International Astronomical Union (IAU e-mail harvard.edu/iau/info/astrometry.html). Numerous written communications between Dr. Durig and the Center were observed in the laboratory, indicating the close coordination among professional asteroid/comet hunters and the certifying agency. More than 275,000 asteroids, nearly all residing in or near the plane of the ecliptic (plane of the solar system), have been found to date by the world's researchers in this field, some of whom are amateur astronomers. 

For the final part of the program, everyone moved out onto the observatory building roof where SCT's and Dobsonians were set up to observe Saturn, Jupiter, the Moon, the Orion Nebula, and other available objects. 

Our thanks go to Dr. Durig and staff for a very interesting program. BAS hopes to return to Sewanee for another visit, possibly this summer. 

(Update: In an e-mail to BAS on 4-22-05, Dr. Durig reported that he and his students discovered three new main belt asteroids, designated 2005-HD, HB3, and HY2, during the previous weekend.) 

Follow-Up: This is only a dream for the future for most of the BAS members, whose telescopes are not ccd equipped. However, did you ever think that someday you might enjoy beginning your own search for asteroids and comets using your equipment at your best sky viewing location? Perhaps you could be an amateur astronomer who discovers the next "near earth object" (NEO), mountain size or larger, which will cross the path of the earth's orbit at an uncomfortably close distance and threaten a catastrophic collision. For all BAS members no matter what your present equipment,, Dr. Durig is providing a "HOW TO" guide for those sky observers who might someday be interested in a ccd observing program for asteroids and comets. The document is titled, "Guide to Minor Body Astrometry", and copies will be handed out to BAS members at the May meeting.

Respectfully submitted by Bill Seymour

in absence of Gary Caldwell

REMINDER

Your annual BAS dues of are now due on June 1, in accordance with the adopted amendment to the by-laws. They are as follows: REGULAR $15.00, REGULAR ASSOCIATE $7.00, JUNIOR $8.00, JUNIOR ASSOCIATE $5.00. Your Sky & Telescope or Astronomy subscription will continue to be handled as in the past. When you receive your subscription reminder card, submit it to:

David Witt
4503 Cove Lane
Chattanooga, TN 37415-2306

Along with the group subscription rate of $32.95 for Sky and Telescope, or $29.00 for Astronomy.

DEADLINE

All articles and other materials for publication in the next STAR are due no later than Wednesday, April 6th. The following media are acceptable: hard copy, disk (IBM), video tape (VHS), prints, or e-mail to bas@chattanooga.net or stramey@catt.com and attach a file or mail to:

Steve Ramey
109 Sioux Trail
Ringgold GA 30736

PHOTOGRAPHS ARE ALSO ACCEPTABLE.

ORION ACRES DIRECTIONS:

FROM NORTH HAMILTON COUNTY: From 27 (corridor J) take hwy. 111 to Dunlap, continue through the Sequatchie Valley up the next mountain (Cagle Mountain). When you reach the summit about 5 miles turn LEFT onto hwy. 399 (sign reads 'to Savage Gulf State Park' Stay on 399 until it ends, which will be in Grundy Co. Now make a LEFT onto hwy. 108 South. This goes thru Palmer TN. Continue on 108 up to a higher elevation. When this levels off, turn RIGHT onto Palmer Fire Tower Rd. This is a large open area with possibly trucks loaded with timber for the paper mills. Orion Acres will be on the RIGHT about 8 tenths mile. A sign will be posted at 7pm on Saturday May 7th.

FROM INTERSTATE 24 (to Nashville): Go to the Dunlap/Whitwell exit (#155). This is hwy. 28. Exit right and keep on 28 for about 11 miles, passing Hardee's on your left. Continue through the stoplight and take the next LEFT on Hwy. 108 North. Continue another 11 or so miles. You will see 'Grundy County' sign. Take the next left. This is Palmer Fire Tower Rd. Go 8 tenths of a mile and Orion Acres is on the RIGHT. There will be a sign posted at 7pm on Saturday, May 7th.

 

SS-433 UPDATE

In 1996 we had the privilege of looking over the shoulders of Dr. Klaus Jagger as he took data on the strange object in the constellation of Aquila. Since then it has been a fascination of mine to try to understand the mechanism of the jets and the motions of this binary system. 

The most recent Chandra image of SS 433 shows two high speed lobes of 50 million degree gas 5 trillion kilometers apart on opposite sides of a binary black hole system. The binary system, which has a diameter several million times smaller than the distance between the lobes, consists of a massive star and a black hole with a disk of hot matter. Material is ejected from this disk in narrow jets that slowly wobble or precess around a circle. 

The detection of the hot gas lobes so far away from the central black hole came as a surprise since earlier observations by Chandra and the Hubble Space Telescope had indicated that gas was cooling as it expanded away from the vicinity of the black hole in narrow jets. This led scientists to predict that no hot gas would be found further than a few million kilometers from the black hole. 

This observation implies that the gas in the jets has been reheated, most likely by collisions between blobs of gas. Long-term optical monitoring observations have shown that matter is ejected every few minutes from the vicinity of the black hole in bullet-like gaseous blobs. The blobs apparently travel outward at about a quarter of the speed of light for several months without colliding until a faster blob rear-ends a slower one, precipitating a pileup that reheats the gas. 

SS 433 is similar to the XTE 11550 binary system, in that they both involve black holes that are producing high speed jets of gas. However, there are significant differences. The X-ray emitting lobes in XTE J1550 are observed to be much further from the black hole than those in SS 433, and the X-rays from the XTE J1550 lobes appear to be produced by a magnetized cloud of highly energetic electrons, not clouds of hot gas as in SS 433. These differences might be due to the mass of the companion stars, which are quite dissimilar. In XTE J1550, the companion star has a mass similar to that of the Sun, whereas in SS 433, the companion star's mass is estimated to be almost 20 times that of the Sun. Perhaps the rapid rate of evaporation of matter from the massive star could affect the behavior of the jets in SS 433.

Good Seeing!

Here are some pictures of the moon that Victor took the other night with his LPI camera through his 5 inch refractor. Enjoy!

 

 

 

 

Report from the May 7th star party at Orion Acres

It's been a while since I had been to Orion Acres. In fact, it's been a while since I've had an opportunity to do any observing at all. But the weather looked good, I didn't (for once) have anything tugging me the other way, and my wife suggested I take advantage of the planned star party.

My first obstacle was getting my 13.1" dob to the mountain. I had traded cars since I had last had it out, and I wasn't sure it would fit in my Buick. With a little pushing, shoving, a shoe horn, and some tie-down rope, I finally got my gear packed and headed out for the mountain.

It had been so long since I had had an outing that I had to stop at a local drug store first to replace the batteries in my red flash light. While I was there, I noticed a can of "Off" on the shelf. I figured that was essential gear so I bought one. I got to the site just as the sun was setting.

The drive wasn't bad. It was about 56 miles from my home in Ringgold, but by following Victor's directions around the freeway to Jasper, it was faster than my old route over Suck Creek Mountain. Victor, Jim, and, Heriberto were already there, along with Victor's and Heriberto's wives. Later we were joined by another couple who were friends of Victor's. The night started out with a little bit of high cirrus haze, but it quickly dissipated and I got down to business checking in on some of my old friends. M65, M66, and M13 to name a few. I had wondered on the way up if I would be able to remember how to navigate my way around the sky since it had been so long since I had observed. But some things, like riding a bicycle, stay with you and before long I was hopping from one object to the next just like in the old days. Even though I mis-identified M97 as the Eskimo nebula instead of the Owl nebula. (Senior moment, I guess.)

Being back in the saddle I remembered what had drawn me to the sky in the first place. I will definitely be back soon. By the way, the evening was so perfect that I didn't even have to use the insect repellent.

Steve Ramey