ASTRONOMY CLUB OF TULSA

OBSERVER

E-mail version

June 1999

ACT, Inc. has been meeting continuously since 1937 and was incorporated in 1986. It consists of approximately 150 members and is a nonprofit; tax deductible organization dedicated to promoting, to the public, the art of viewing and the scientific aspect of astronomy.

WHAT:

The Astronomy Club of Tulsa Meeting

WHEN:

Friday June 25th, 1999 at 7:30 P.M.

WHERE:

Room M1 inside Keplinger Hall, the Science & Engineering Building at TU. Enter the parking lot on the East Side of Keplinger Hall from Harvard and 5th Street. This will take you directly toward the staircase to enter the building. Room M1 is the first room on the left.

FUTURE MEETINGS:

July 30th, August 27th, and September 24th

THIS MONTH'S PROGRAM:

Dr. Steve Balog will be speaking on the subject of "Black Holes". Steve has been into both amateur and professional Astronomy for over 25 years. He has a Ph.D. in Particle Astro-Physics and has done considerable research into the nature and theory of Black Holes. He is an Instructor at St Marks School in Dallas, Texas and is both the Planetarium director and Observatory director. He also serves on the Board of Directors of the Texas Astronomical Society. Steve is an excellent and dynamic speaker. I am very excited about having him as our guest speaker this month!

LAST MONTH'S PROGRAM:

I am very sorry that Dr Steve Balog was unable to be at our meeting as scheduled. He had already left Dallas and was on his way when he encountered major automobile problems and was unable to finish the trip to Tulsa. His wife had to go and get him because his vehicle could not be driven home. In a conversation with Dr. Balog this past week He has assured me that his vehicle has been thoroughly repaired and He will be here to speak on the 25th.

As a result of Dr Balog's inability to be present to speak last month I quickly decided, at the last moment, to show the video "The Creation of the Universe". This program has been shown on PBS several times and is an excellent rendition of the basic concepts of cosmology starting with the present and moving back in time to the moment of creation (the big bang). Except for the length of the program, I think every one enjoyed it quite well! Since our speakers usually speak for about an hour, a two-hour video was a little lengthy for which I apologize.

A WORD FROM THE PRESIDENT:

On Saturday, June 5th we had a workday at the observatory. The following people helped out: Grant Cole, Steve Chapman, Dennis Mishler, Barbara Mishler, Gerry Andries, Rusty Fletcher, Sally Able, and Teresa Kincannon. The Classroom area, hall and restroom were cleaned. The entire grounds were mowed and trimmed. Gerry Andries fixed the toilet that would not flush, and a number of other small jobs were done. A big, special "thank you" to everyone who worked at the observatory on workday!

Evidently, someone failed trying to break into our observatory again. They broke the doorknobs off both the observatory doors. Last week Blake Champlin removed the doorknobs and is in the process of getting them fixed. The observatory is still locked using the dead bolts. Also, last week James Liley made the necessary measurements to design the components that are needed to fix the problem of water leaking around the dome. No club money has been spent yet, but we will be using part or all of the $1,500.00 authorized at the May club meeting to fix the water leak around the dome.

On June 11th we had our monthly club star party. It turned out quite well considering how poor the weather has been lately. Mars still showed considerable detail. Through the observatory scope and through KC Lobrecht's newly acquired 5-inch refractor I could see both polar caps on Mars. The Lagoon Nebula looked great through David Stine's 10-inch Dobsonian. As I was leaving, after midnight, several people were still observing. I stopped to take a look through Cody Glossop's 8-inch Meade reflector. What a beautiful view!

SCHEDULED EVENTS:

06-22-99 Tue ORU Academy (35) w/ Kevin Manning

06-23-99 Wed Back up for 06-22-99

06-26-99 Sat Sapulpa Girl Scouts (8)

07-09-99 Fri Club star party

08-06-99 Fri Club star party

Anyone interested in volunteering to help on nights when we are having groups at the observatory please call Gerry Andries. He would greatly appreciate your help!

On Friday Night, July 9th, the ACT Club star party will be held at the RMCC Observatory. All club members, their families, and friends are welcome. The sun sets at 8:44 PM that evening, so the Observatory facility should be open by about 8:15 PM for everyone who wants to set up their personal telescope. For directions to the Observatory or in case of poor weather call Gerry Andries at: 918-Phone.

=========================================

June SKY FORUM

By Don Cole

Pluto, is the ninth planet from the sun and outermost known member of the solar system (see Solar System in Astro Dictionary). Pluto was discovered as the result of a telescopic search inaugurated in 1905 by the American astronomer Percival Lowell, who postulated the existence of a distant planet beyond Neptune as the cause of slight perturbations in the orbital (see Orbit in Astro Dictionary) motions of Uranus. Continued by members of the Lowell Observatory staff, the search ended successfully in 1930, when an American astronomer (the late) Clyde William Tombaugh found Pluto near the position Lowell had predicted. The new planet's mass, however, seemed insufficient to account for the perturbations of Neptune, and the search for a possible tenth planet continues, even today.

Pluto revolves about the sun once in 247.7 years at an average distance of 5.9 billion km (3.67 billion mi). The orbit is so eccentric, that at certain points along its path, Pluto is closer to the sun than Neptune. No possibility of collision exists, however, because Pluto's orbit is inclined more than 17.2 degrees to the plane of the ecliptic and never actually crosses Neptune's path.

Visible only through large telescopes, Pluto is seen to have a yellowish color. For many years very little was known about the planet, but in 1978 astronomers discovered a relatively large moon orbiting Pluto at a distance of only about 19,000 km (about 12,000 mi) and named it Charon. The orbits of Pluto and Charon caused them to pass repeatedly in front of one another from 1985 through 1990, enabling astronomers to determine their sizes fairly accurately. Pluto is about 2284 km (1420 mi) in diameter, and Charon is about 1192 km (740 mi) in diameter, making them even more closely a double-planet system than are the earth and its moon. Pluto was also found to have a thin atmosphere, probably of methane, exerting a pressure on the planet's surface that is about 100,000 times weaker than the earth's atmospheric pressure at sea level. The atmosphere appears to condense and form polar caps during Pluto's long winter.

With a density about twice that of water, Pluto is apparently made of much rockier material than are the other planets of the outer solar system. This may be the result of the kind of cold-temperature/low-pressure chemical combinations that took place during the formation of the planet. Many astronomers think Pluto may be a former satellite of Neptune, knocked into a separate orbit during the early days of the solar system. Charon would then be an accumulation of the lighter materials resulting from the collision.

*** Astronomy Dictionary ***

(ORBIT), the path or trajectory of a body through space. A force of attraction or repulsion from a second body usually causes the path to be curved. A familiar type of orbit occurs when one body revolves around a second, strongly attracting body. In the solar system the force of gravity causes the moon to orbit about the earth and the planets to orbit about the sun. The orbits resulting from gravitational forces, which are discussed here, are the subject of the scientific field of celestial mechanics.

(SOLAR SYSTEM), Our stellar-planetary unit consisting of the sun; the nine planets and their satellites; the asteroids, comets, and meteoroids; and interplanetary dust and gas. The dimensions of this system are specified in terms of the mean distance from the earth to the sun, called the astronomical unit (AU). One AU is 150 million km (about 93 million mi). The most distant known planet, Pluto, has an orbit at 39.44 AU from the sun. The boundary between the solar system and interstellar space-called the heliopause-is estimated to occur near 100 AU.

*** From The Cargo Bay ***

Once the Orbiter is in orbit how does it maneuver in space? As mentioned earlier the shuttle has several types of engines, but for maneuvering in space there are basically two types of engines. The (SSME) or space shuttle main engines is one of the most advanced rocket engines ever built. It burns liquid hydrogen and liquid oxygen to produce a rated thrust of 375,000 pounds each at sea level. The thrust can be varied from 65 percent to 109 percent of the rated value. This engine is used at launch along with the SRB's to boost the shuttle into orbit and are NOT used to maneuver in space. The first type of engines used are the (OMS) or orbital maneuvering system engines, these are mounted in the external pods on each side of the aft fuselage of the shuttle. These engines are used during orbital insertion and deorbit burns, plus, the OMS pods provide thrust for large orbital changes. Each engine has a rated thrust of 6,000 pounds. The propellants are Monomethal hydrozine (the fuel) and nitrogen tetroxide (the oxidizer). The second type of engines are the (RCS) or reaction control system engines. This is a system of 44 small rocket engines that maneuver the shuttle in space around the yaw, pitch, and roll axis. There are 38 primary RCS thrusters with 870 pounds thrust each and 6 secondary thrusters with 25 pounds thrust each. (Once the mission is complete and you are ready to come home, What are the first steps (in a number of steps) before you can begin your journey back?)

So until next month Dark Skies and Steady Seeing to You ...

Reference Material :: "Astronomy, A self-teaching guide." by Dinah L. Moche (4th ed.) "Guide to the Stars" by Leslie Peltier. " Astronomy, For the Earth to the Universe" by Jay M. Pasachoff (3rd ed.)

========================================

DAVID'S ASTRO CORNER

"IMPACT Earth, IMPACT Moon, and a Mysterious Star, and the End of the World!"

By David Stine

Recent calculations of asteroid 1999 AN10 have revealed that there is an outside chance that it could hit the earth in less than 50 years according to Paul W. Chodas of the Jet Propulsion Laboratory. Analysis by several dynamists shows that the asteroid would pass by earth as close as 30,000 kilometers on August 7, 2027. The uncertainty of where 1999 AN10 will be when it passes earth during that year allows for unknowns that could send it crashing into earth in 2044 or 2046. Continued observations of the asteroid will continue and eventually determine even a more definite orbit to determine how exact these calculations are. For a list of potentially hazardous asteroids go to the web address: http://cfa-www.harvard.edu/iau/lists/PHACloseApp.html.

July 21st is the big day or should I say end day. If you follow Nostradamus, the ancient prophet, according to the analyzers of his prophecies, the world is predicted to end on July 21st, 1999. I think there should be analyzers for analyzers. We should all gather at the observatory that night for an "End of the World Star Party."

Mark your calendars for July 31st if we are still here. NASA is planning to plummet the Lunar Prospector spacecraft into a crater on the moon. The plan is to raise the orbit of the spacecraft and reduce its velocity to force a collision near the Moon's south pole at 9:51 UT. The reason is to try and verify if this area may have frozen water. When the spacecraft impacts, it should throw up a plume of debris containing water. Prospector's impact energy could heat the ice to 127 deg. Celsius. The Hubble Space Telescope and McDonald Observatory will be watching to look for spectral indications of water or it's molecular byproduct OH. Why are we crashing a perfectly good operating spacecraft, because like many NASA projects, money has run out? Will backyard telescopes be able to see the impact, no one knows for sure, but like Jupiter it might be worth observing the moon that night just in case. According to Dr. David Goldstein of the University of Texas, "a positive spectral detection of water vapor or its byproduct, OH, would provide definite proof of the presence of water ice in the lunar regolith." By crashing into the Moon's south lunar poles, Lunar Prospector could provide the first incontrovertible proof that water is really there and may show whether there is enough water on the moon to support human colonies in the future. The plan is awaiting final approval by NASA administrator Daniel Goldin.

What's going on with Eta Carinae. Within a few short weeks the star has tripled in brightness, making astronomers scratch their heads in amazement. As Rick Wells would say "What's the Deal". For those who don't know, Eta Carina is a huge massive star in the Southern Hemisphere. It is 100 times more massive than our Star; it radiates five million times more power. Kris Davidson, a University of Minnesota astrophysicist said, "Occasionally something happens in astronomy that is so bewildering that it makes astronomers nervous." In layman terms, "This is weird." The star is 7,500 light years from earth. Astronomers earlier had predicted that Eta Carina would end its days as a supernova or possibly a hypernova in the future, but not ours. To explain the brightening, Davidson and his colleagues turned the Hubble Space Telescope to look at the star and what they found was so strange that it defied explanation. It appears that a smaller double lobed structure is growing within the larger pair of lobes. It is this inner set of cones that has tripled in brightness since April. According to Theodore Gull, the enormous heat inside these cones may be responsible for the brightness. "Some of the brightness we're seeing could be the result of ionization within the nebula." he said. "However, its also possible that Eta Carinae is about to erupt again." Davidson said that the brightness increase was a complete surprise because we weren't expecting any major outburst for a few decades yet. Unfortunately, we Northern Hemisphere observers never get to see Eta Carinae, so for the action you will have to go below earth's equator. (Excerpts from Sky and Telescope's News Bulletin, an internet service weekly of new activities in astronomy http://www.skypub.com/news/news.html) and NASA Space Science News http://science.nasa.gov/newhome/headlines/astr.htm

From the local side of Astronomy, several members had an enjoyable observing session at the RMCC Observatory, Friday evening June 11, during the club star party. We thought we had lost Kevin Manning though. Kevin and Rusty went looking for a rocket that Kevin's O.R.U. group had blasted off the night before and had fallen into the thick brush and trees north of the observatory. Rusty made it back before dark, but no sign of Kevin. We were about ready to set up a memorial for him, as we figured the coyotes had sent him on to a better world, when out of the darkness he came wandering back up the hill. The rocket was never found. The rest of the night we viewed the heavens and met new people. The highlight of the night was seeing a -3 Mg. Iridium Flare, not as bright as they can get, but still impressive. ( I'll devote my entire corner to this subject in the future). We also viewed many satellites. The club's 16-inch scope performed beautifully, showing detailed dust lanes in galaxies, and showing the ring nebula like never before seen. If you haven't been out to the observatory you are missing half of being a member of the Astronomy Club of Tulsa. Someone is usually there just about every night it is clear, which lately hasn't been that often, but when it is clear its the best and darkest place to view the heavens. The next official club star party is Friday July 9, which could be your last chance before the end of the world!

K.C. Lobrecht reported observing Comet Lee just a few degrees south of Venus, Monday evening June 14th at the observatory. The sky was still bright, but the comet popped into her view fairly easily leaving her to estimate its MG. at 6.2 Lee continues to move northwest and will soon be too close to the sun to view, so you better look now. Early July will find Lee at its brightest, but very low in the twilight. By the 10th the comet will be lost in the glare of the sun. Lee will become visible again, but this time in the early morning, by August 11th moving through Auriga just in time for the Perseid Meteor Shower. Lee will climb higher into the sky, and by the end of September, will be an all night object in Cassiopeia.

One of our members, George Brenner, has just returned from the Mid Central Astronomy meeting which was held in Fayette, Missouri. Several of us have been to that college town in the past for meetings. What is unique at Fayette, is their observatory, which holds an Alvin Clark 12-inch refractor used by many famous astronomers in the past. George got to view Mars and Venus through the scope. The speakers were a little boring according to George, but overall it was a good meeting. One speaker was in charge of coating the mirrors for the x-ray telescope NASA is waiting to launch and the other speaker analyzed moon rocks.

Ron Wood continues to improve. Maura says he doesn't have to go back to the neurologist for six months. He is suppose to see his plastic surgeon within the week and a date is to be set for his operation. They are going to try and graft the entire scalp in one graft. Maura said to tell everyone thanks for the e-mails they have been getting. Ron has trouble typing replies as his left arm is still messed up, but he really appreciates the e-mails so keep them coming. Thanks for all the well wishes.

That's it from my Astro Corner this month and possibly my last, but if we make it past July 21st, I'll be here bringing you all the latest astronomy news in my corner. Nostradamus Who?

-------------------------------

Astronomy Club meeting dates for 1999.

The club will meet the last Friday of each month except for November and December when a holiday will interfere with the last Friday. The November meeting will be on the 19th, and the December meeting will be on the 17th.

The dates are:

25 June

30 July

27 August

24 September

29 October

19 November

17 December

That’s all folks…