ASTRONOMY CLUB OF TULSA

OBSERVER

E-mail version

July 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 July 30th, 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:
August 27th, September 24th, and October 29th

THIS MONTH'S PROGRAM:

During the first part of our meeting we will continue discussion on the purposed new telescope to be placed in our Observatory. Last month several people mentioned that they will be unable to attend the July meeting and wanted to know if it would be possible to vote absent-tee. After discussing this issue with the board, and since we consider this matter to be of utmost importance, we have decided to make some changes to the voting procedure for the benefit of the entire club membership. At this next meeting we will continue the nominations of various proposed telescopes and will allow approximately five minutes discussion on each. At the conclusion of the discussion we will vote, by secret ballot, on all nominations. The two telescopes that receive the highest number of votes will be announced at this meeting and placed in the run-off. The final vote on these two telescopes plus a third option "to do nothing at this time" will be discussed and voted on (again by secret ballot) at the August meeting. This will give each member of the club an entire month to think about how they want to vote. During the month of August absent-tee voting on the final two telescopes will be permitted the following three ways:

First, a club member can vote absent-tee by expressing which of the three options they are casting their vote for by sending an E-mail to Richie Shroff at: astroclub@b-its.com Please make sure your full name is included in the body of the E-mail message. The cut off time for sending an E-mail is noon on Friday August 27th.

Second, a club member can vote absent-tee by expressing which of the three options they are casting their vote for and mailing a letter to: Astronomy Club Of Tulsa, P.O. Box 470611, Tulsa, Ok. 74147-0611. Please make sure you sign the letter including your full name. Your letter must arrive at our P.O. Box by Friday August 27th in order for your vote to get counted.

Thirdly, a club member can vote absent-tee by expressing which of the three options they are casting their vote for and sending a sealed letter, containing their vote, to the August 27th club meeting through a friend. When voting absent-tee your name must be included in the letter. A person cannot vote both absent-tee and anonymously.

After the club business is completed this month John Land has tentatively arranged for a special guest speaker. Mark Abbott works for TRW out of CA and does research at the White Sands proving grounds. He is an optical engineer and works on "Star Wars" type defense missiles. His field of expertise is in high-energy lasers and adaptive-optics. At the time this article is being written John is trying to get back in touch with him to confirm him as our guest speaker. Originally, He had expressed a very positive interest in speaking to our club on July 30th. Hopefully he will be able to speak at our meeting!

LAST MONTH'S PROGRAM:

Dr Steve Balog of Dallas, Texas gave us a very special treat on the subject of Black Holes. His speech was very informative using visual aids with Hubble Space Telescope pictures of Black Holes. I thought the question and answer session at the end of his lecture was also great! Thank you Dr. Balog for a wonderful evening!

A WORD FROM THE PRESIDENT:

I just want to write a line or two expressing my appreciation to all the club members for your support during my brief time as your president! For the benefit of those of you who do not know I am a licensed, ordained minister and I am moving to the Houston, Texas area to pastor a church. Of course I love astronomy: "The Heavens declare the Glory of God" Psalm 19:1. I plan to join the Houston Astronomy Club in the very near future. But, The Astronomy Club of Tulsa will always hold a warm place in my heart. I've made some very good friends. I couldn't begin to name you all here in this article, just know that your friendship is very special to me and keep the love and passion for the stars burning in your hearts. Thank you for allowing me the honor of serving as your president!

SCHEDULED EVENTS:

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, August 6th, 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 8:24 PM that evening, so the Observatory facility should be open by about 8:00 PM for anyone who wants to set up their personal telescope. For directions to the Observatory or in case of poor weather call Gerry Andries at: 918-369-3320.

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JULY SKY FORUM
By Don Cole

I want to change course slightly at first and talk about meteors. A meteor is a small solid body entering a planet's atmosphere from outer space and raised to incandescence (caused to glow) by the friction resulting from its rapid motion and the Earth's atmosphere. Brilliant meteors, known as fireballs, occur singly and generally consist of a luminous head, followed by a comet-like train of light that may persist for several minutes; some, called bolides, have been seen to explode with a sound like thunder. Fainter meteors, called shooting or falling stars, usually occur singly and sporadically. At intervals, however, hundreds of such meteors occur simultaneously and appear to emanate from a fixed point. These swarms are called meteoric showers and are named after the constellation in which they seem to have their point of origin. Some appear annually on the same days of each year and are called periodic showers; others occur infrequently and at varying intervals. The periods of meteoric showers generally coincide with those of certain comets. Most meteors are dissipated in flight and fall to the earth as dust; a meteor that reaches the surface of the earth or another planet is called a meteorite (See Meteorite). The reason I decided to discuss meteors at this time is that we were at Broken Arrows' Fourth of July fireworks demonstration at Indian Springs on the 3rd and just after the Sun had set around 9:15 PM. As we sat looking to the south, and 20 degrees above the horizon we saw a fireball, it came in from the East and went straight West (from our perspective), perpendicular to the horizon. It left a trail about 8 to 12 degrees long and broke apart as it brunt out, we watched it for about 20 to 30 degrees across the horizon. What a way to start of the fireworks display.

Since we have checked out all the (known) planets in our Solar System, let us look at some of their (satellites) this is a secondary object that revolves in a closed orbit about a planet or star, referred to as the primary of the satellite. The best-known satellite is the earth's moon-just as the earth itself is a satellite of the sun-although the moon and earth are close enough in size to be considered sometimes as a double-planet system. The motion of most of the solar system's known satellites about their planets is direct-that is, from west to east-and in the same direction as the rotation of their planets. Only a few satellites of the large outer planets revolve in the retrograde direction-that is, from east to west-and opposite the direction of rotation of their planets; they probably were captured by the planets' gravitational fields some time after the formation of the solar system. Many astronomers believe that Pluto, which moves in an independent orbit about the sun, is an escaped satellite of Neptune; Pluto itself was recently discovered to have a satellite. Some specific information about the individual satellites will be given in upcoming articles.

*** Astronomy Dictionary ***

METEORITE : This is a meteor that reaches the surface of the earth or of another planet before it is entirely consumed. Meteorites found on earth are classified into types, depending on their composition: irons, those composed chiefly of iron, a small percentage of nickel, and traces of other metals such as cobalt; stones, stony meteors consisting of silicates; and stony irons, containing varying proportions of both iron and stone. Although most meteorites are now believed to be fragments of either asteroids or comets, recent geochemical studies have shown that a few Antarctic stones came from the moon and Mars, from which they presumably were ejected by the explosive impact of asteroids. Meteorites generally have a pitted surface and fused charred crust. The larger ones strike the earth with tremendous impact, creating huge craters. The largest known meteorite, estimated to weigh about 55 metric tons, is situated at Hoba West near Grootfontein, Namibia.

*** From The Cargo Bay ***

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? Once the Orbiter has finished its' mission one of the first things that needs to be done and one of the last things to be accomplished in space is to close the radiators and shuttle doors. Turn the Orbiter around so it is facing backwards and fire the OMS pod engines to slow the Orbiter for reentry. The Orbiter is then pitched around again to face nose first at an attitude of 28 to 38 degrees nose down for reentry. At an altitude of around 400,000 feet and 5,000 miles from the landing site the Orbiter begins to reenter the Earth's atmosphere. At what speed does the Orbiter enter the Earth's atmosphere ? How does the shuttle slow down ? and, About how hot does the exterior of the shuttle get on reentry and what causes the shuttle to get hot anyway ?

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.)

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DAVIDS ASTRO CORNER
NEW COMET, PERSEID METEOR SHOWER, UPDATE ON COMING LEONID METEOR SHOWER AND ASTEROID 1999 AN10 NEW PREDICTIONS.
By David Stine

On July 13th, Australian amateur Daniel W. Lynn discovered an 8th Mg. comet in the constellation Hydra according to Sky and Telescopes News Bulletin of July 16, 1999. By the time you read this, the comet should be visible from Tulsa, possibly a 7th Mg. object. Comet Lynn (C/1999 N2) passed its closest approach of the Sun on July 23 at a mere 0.76 AU from our Star. It is expected to fade rapidly, so if you are to observe it you better start now. On July 31st, the comet will be near the star Denebelo in Leo at 11h 54.09 min. and +12 degrees 45.3 seconds. On the 5th of August it will be at 12h 10.64 min. and +17 degrees 06.8 secs. On the 10th it will be in Coma Berenices at 12h 22.90 min. and +20 degrees 27.9 secs.

Comet Lee comes back in view in the early morning hours. Look for the comet starting August 10th at 4 AM low in the ENE between Gemini and Auriga. By August 30 it will be high in the ENE sky by 3 AM near the triangle of stars in Auriga 's top.

We are only a few weeks away until the annual Perseid Meteor Shower. Conditions should be ideal as there will be no moon to interfere. The best time will be the early morning hours before dawn on August 13. The shower usually produces some fireballs and from a dark location you should be able to see 50-100 Mg. 4-0 meteors in an hours time. The Earth will enter the traditional stream at 11 PM on 12th of August favoring eastern North American, but Tulsans should get their best view between 1 and 5 AM on the 13th. The International Meteor Organization has been monitoring a new stream of Persieds that may produce even more meteors per hour, unfortunately, the earth passes through this stream at 5 PM on the 12th. I'm sure the observatory will be open the evening of the 12th through the early morning hours of the 13th for viewers wanting to catch the Perseids.

We are just four months away from what could be the most amazing meteor shower anyone here has ever seen. Yes the Leonids are just around the corner. If they are anything like last year, you do not want to miss them. Recent predictions are very good for a major storm. We may not see as many fireballs like we did last year, but the number my increase tremendously. Again the peak favors the Canary Islands, however this peak is very unpredictable as was the case last year. The period of maximum activity during the 1998 shower took place about 12 hours before the earth crossed Comet Tempel Tuttle's orbital plane. The early activity caught many observers by surprise. The good news is this is very similar to what happened in 1965, the year that preceded the great Leonids storm of 1966. Rainer Arlt of the International Meteor Orgainization writes that "the radar, visual, and photographic records of the 1965 Leonids indicate an activity profile which resembles that of the 1998 Leonids. Even the low population index seems comparable. Judging from these phenomenological facts, we may expect 1999 to show a similar shape of activity as in 1966. And what was that shape of activity in 1996, here is an account by James Young at the JPL's Table Mountain Observatory in California:

"This very noteworthy (1966) meteor shower was nearly missed altogether......There were 2-5 meteors seen every second as we scrambled to set up two cameras we had, as no real preparations had been made for any observations or photography. The shower was expected to occur over the European continent. The shower peaked around 4a.m. with some 50 meteors falling per second. We all felt like we needed to put on hard hats! The sky was absolutely full of meteors....a sight never imagined....and never seen since! To further understand the sheer intensity of this event, we blinked our eyes open for the same time we normally blink them closed, and saw the entire sky full of streaks......everywhere!"

The 1966 return of the Leonids was one of the greatest displays in history, with a maximum rate of 2400 meteors per minute or 144,000 per hour. Each month as we get closer I will update you as the Leonid Watch continues.

You may remember that I reported in last month's corner that there was a possibility that Asteroid 1999 AN10 was on a collision course with earth in 2044. Well past photos has saved the earth. Images of the asteroid were found on plates from the National Geographic-Polomar Observatory Sky Survey recently. The trail of the asteroid was measured from the 1955 photographs and the objects orbit has been refined. The revision increased the minimum-possible approach distance to Earth to 386,000 kilometers and moved the keyhole points such that a collision with Earth in four decades was impossible. Long live the Earth.

Last but not least, Ron Wood has had his graft and seems to be doing better. He still has a long way to go though but things seem to be looking up. Maura wants everyone to know how grateful they are for all the well wishes and prayers they have received. As Maura says, in this era of short attention spans, it is nice to know that some people can hang in there with you over the longer term. Thanks again.

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DAVID'S ASTRO CORNER - UPDATE
By David Stine

In last months newsletter, I reported about NASA's Lunar Prospector spacecraft going to impact the Moon. The latest is that it will happen as planned on July 31 at 3:52a.m. CST. The moon will be high in the WSW. There is an outside chance that telescopes as small as 8 inches may be able to discern a dust plume seconds after the impact. The Association of Lunar and Planetary Observers has issued a call for all lunar enthusiasts to monitor the south polar region of the Moon for visible signs of Prospectors impact. The ideal set-up for possibly seeing some kind of evidence of impact would be an 8 inch or larger telescope equiped with a CCD video camera. Lunar observer Charles Shirk says that operators using equatorial mounted scopes should move the scope southward to the farthest southern limb, and they will be close enough to the target area to enclose the environs of the impact crater even at 200x. Those having Moon maps and charts need to simply draw a line between the lunar eastern rims of craters Maginus and Moretus and where that line crosses the limb of the Moon is very close to the location of the impact site. I will have charts at the July 30 club meeting for those who are interested in trying to possibly see any plume from the impact.

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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:

30 July

27 August

24 September

29 October

19 November

17 December

That’s all folks…