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October 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.



The Astronomy Club of Tulsa Meeting


Friday October 29th, 1999 at 7:30 P.M.


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.


November 19th and December 17th


I will be giving a presentation using some lunar samples from Apollo 16 and 17, meteorite samples, and slides from NASA. This month also marks our annual business meeting. There will be nomination and election of officers for the coming year.


Our September meeting focused on our observatory past and present. James Lily guided us through the remarkable history of the structure and the many members who contributed time, money, and effort to make it a reality. There were suggestions that we should record James' talk for future members of our club. Gerry Andres brought us up to date on the status of the building and plans to seal the water leaks that have caused damage to the building interior. Members were invited to attend future board meetings to suggest improvements and possible renovations for the observatory site. We also discussed the need to institute a public star party at the TCC West campus. Although the board and membership suggested an October date for the session, the change to Standard Time and phase of the moon make November 12th a better evening for the party. We have final approval from the TCC staff for this date.


There will be a public star party at Tulsa Community Collage West Campus on Friday, 12 November. Everyone bring your telescopes and be there early. On Monday, 15 November, Jeff Goldstein from the Challenger Center will be at the Tulsa Air and Space Center to speak on Windows to the Universe. Admission is $4. They have asked if it's clear for some telescopes to be set up outside for public viewing.


I want to personally thank the membership for allowing me to serve as your acting president for the last three months. An excessive amount of personal commitments and problems prevent me from serving in this post for the next year. I plan to actively assist the new president and vice-president. Please consider and bring to the business meeting, your nominations for club leadership.



Gerry Andries

It looks like the Starry Messenger Press is NOT out of business as we had thought last year! They sent me a sample in the mail, and it is excellent in quality as always. For those who want one, call (Phone) or email (< Gerry Andries e-mail > ) me unless they are going to be at the October meeting to sign up. They must be ordered before the end of November in order to get the discounted price of $8.95 for ordering 10 to 35 copies. Wall calendars are also available, but they are $18.00 each.


David's Astro Corner

"Novembers Rain of Meteors and Naked Eye Comet Coming"

We are just weeks away from what could be the meteor shower of a lifetime. The only problem is we may be in the wrong part of the world to see it. Peak time is predicted at 9:08 p.m. CST the evening of November 17. If this holds true, people in Europe and Africa will see the spectacle, while we will still be waiting for the Leonid radiant to rise. We would still see the late edge of the shower after midnight November 18 when the radiant rises. However since 1966, the showers peak has been arriving about two hours later each year, which would make this year's peak, arrive at 11:15p.m. CST on November 17. This would favor people in Western Europe and West Africa but also pose the possibility of people near the East Coast of North America to see Earth Grazing meteors skimming horizontally through the upper atmosphere. Robert Lunsford, secretary-general of the International Meteor Organization claims the best place to observe if in North America is as far east as possible. Predictions as how strong the shower will be, is anywhere from as many as only a few to 7,000 per hour. Just a few hours later for the peak would place it right over our heads and if last year was any indication we should still see a good show in Tulsa. Its anybody's guess, if the shower hits 4-8 hrs earlier than anticipated, the show would be in eastern Asia and Australia, but if it were to peak 4-8 hrs late Americans would be looking into the eye of the storm according to Joe Rao, meteorologist for News 12 Westchester and an instructor at New York's Hayden Planetarium. I'm sure we will be gathering at the observatory the night of November 17 and the morning of the 18th in anticipation of a show like last year. It may not be as exciting as last year; but then again it might even be better. The only way to know for sure is to be there ready to observe. David Asher and Robert McNaught have studied the motions of particles ejected from the parent comet, Comet Tempel Tuttle, within the last 200 years. They are predicting a maximum hourly rate of 1,000-1500 for this November and 2000. They go on to say that the best is yet to come, predicting hourly rates of 10,000-35,000 in 2001 and 25,000 in 2002. We can only wait and hope they are right.

A new comet was discovered on September 27th by MIT Lincoln Laboratory's LINEAR robotic telescope in Socorro, New Mexico. It is very faint presently but by the time it reaches perihelion July 24th, 2000 if may become a naked eye object at Mg. 3 or 4. The comet is expected to come inside Earth's orbit to about 0.75 astronomical unit from the Sun or roughly the same distance as Venus from the Sun. By July 16th around the time of the total lunar eclipse the comet should be visible low in the northwest evening sky without any optical aid. This is one to watch for. I will keep you updated on C/1999 S4 as it becomes visible for us in the near future.

Comet C/1999 P1 (Machholz 2) will be brightening rapidly from Mg. 16 in October to a respectable 8.0 by the end of November. It will slowly move from Serpens in the latter part of October through the southern part of Scutum the first of November to just WNW of Capricornus by November 30. It will be visible at this time between 7p.m.-9p.m. in the SW. This comet may brighten even further in December as it reaches perihelion on December 9. In the year 1994 the comet broke apart. No visible signs of the other components were detected. R.H. McNaught at Siding Spring recovered the comet on August 3, 1999.

One of the best comet news service, Comet Rapid Announcement Service, is discontinuing operation December 2000. The last issue will be the December 2000/January 2001, completing 14 full years of publication. We are sorry to see the service discontinued as it brought the most complete coverage and charts of newly discovered comets. The reason for discontinuing was that information about comets is freely available on the Internet Maybe so, but CRAS was a very informative publication and well worth the subscription fee and will be missed by us comet enthusiasts.


If you have been thinking about buying a solar filter for your scope but have been putting it off, you had better order it now. The Sun is becoming very active with large groups of sunspots moving across its surface every day. Late in September a series of minor to moderate geomagnetic storms have triggered auroras along the northern tier of the states and may have affected some power systems in the northern latitudes. This recent increase in geomagnetic activity is just a sampling of more to come as the Sun approaches the maximum of its 11-year sunspot cycle in mid 2000. The action continued in October, as the sun erupted three times from October 12 to October 13, sending coronal mass ejections away from the direction of the earth. These ejections can carry up to 10 billion tons of plasma traveling at speeds as high as 2000 km/s. When they collide directly with Earth they can excite geomagnetic storms causing satellite communication failures and in extreme cases, induce electric currents in the Earth and oceans that can interfere with or even damage electric power transmission equipment. The good news is that increased levels of solar activity will likely trigger dazzling auroral displays at mid-latitudes. The latest Solar Flare Alert came on October 14 where a small X-class solar flare erupted from a group of active sunspots. At that time this group of sunspots was nearing the central meridian of the Sun. Forcasters were predicting additional fare activity for the next 4-6 days and may result in associated coronal mass ejection trajectories that are pointed to Earth. At that time the possibility of intensified levels of geomagnetic and auroral activity were high. This region should provide amateur solar observers to observe dynamic changes in sunspot activity. Those with hydrogen alpha filters should be able to see subflares, point brightening, and surging should be possible. Now is the time to get that solar filter and start observing the active Sun. If you would like to get Solar Alerts contact: and in the body of your e-mail type subscribe. Also check out the following sites for more solar information and real time images of the sun: http// and At the last site images of the Sun are updated once every minute when the Sun is above the horizon. Also with the increased activity of the Sun solar filters are going to be high in demand, so don't wait too long or you might have to wait for a back order. Good sources are Thousand Oaks, Orion and Astronomics.


The sun just keeps on erupting. Since the last report more solar flare alerts have been issued. On Oct. 21 a strong disturbance had been detected by the ACE spacecraft upstream of the Earth. This disturbance was expected to impact the Earth's magnetosphere. There was a good chance for auroral activity in the northern states. It is likely that this disturbance is the compressed shock front of a correlating interaction region that is being driven by the high-speed solar wind stream of a well-placed and recurrent solar coronal hole. I viewed the sun Thursday and it is covered with several large groups of sunspots. This sunspots are where flares can erupt any minute and send plasma to earth. To keep alert of this activity visit and follow the instructions.


If that's not enough activity for the Sun, it's also going to be visited by Mercury, adding an extra spot on its surface to confuse you. What will be the last transit of Mercury or any transit of any kind until May 11, 2391, yea that's correct 2391, on November 15 you have the opportunity to view this sight that few before or after will have. You don't want to miss it. On November 15 between 3-5 p.m. CST depending on your location, Mercury will enter the solar limb as a round black dot roughly a third of the way from the north around to the East Point of the solar limb. Use as high power as possible when observing and always use a solar filter. You can get a customized prediction for your location by sending a self-address stamped envelope and give your latitude and longitude of your observing site to the nearest 0.01 degree or to the nearest arc minute to John Westfall, P.O Box 16131, San Francisco, CA 94116. The closest cities I have seen for predictions are St. Louis at 1st contact 3:11p.m., Denver - 2:11p.m. and Chicago 4:11p.m. Check out Sky and Telescope November issue pages 108-112 for more details. Again you are very privileged to be able to view this as no one will be able to see another transit until the year 2391! Don't miss it.


Reports have been streaming in from the northern states of beautiful and amazing aurora observations just in the last few days. In New Jersey, green curtains to the north, occasionally intense diffuse red glow to NE sky lit by 90% moon. Auroras are very rare at this location. In South Dakota an observer writes; "... amazing I was awoke at 1a.m., couldn't sleep, sky was a bright green, aurora extended almost directly overhead. Almost entire North horizon, 1st beams shooting up and balls of light shooting up, then curtains of light like pouring over an upside down water fall, one burst of red light, very bright green, white prevalent lines in beams, ball fuzzy bomb explosions flying across the sky." And in Minnesota; "I have lived here 40 years. I have never seen such bright aurora. It also went more than 90 degrees overhead all the way from the horizon and all the way east to west. I live near a large city, in the suburbs and it was very high and visible even with a nearly full moon. A truly impressive display." And as far south as Colorado; red and green curtains were observed. Many of the northern state observers felt that many southern states should be able to see this auroras as high in the sky as they reached, so you might want to start looking after midnight toward the northern horizon.

That's it for my Astro Corner this month, hope to see everyone for the Leonid Shower November 17-18.



By Don Cole

This month let us move a (little) further out into the realm of space and get into the domain of the galaxies in particular the Milky Way Galaxy. The term Galaxy, brings to mind a massive ensemble of hundreds of millions of stars, all gravitationally interacting, and orbiting about a common center. All the stars visible to the unaided eye from earth belong to the earth's galaxy, the Milky Way. The sun with its associated planets is just one star in this galaxy. Besides stars and planets, galaxies contain clusters of stars; atomic hydrogen gas; molecular hydrogen; complex molecules composed of hydrogen, nitrogen, carbon, and silicon, among others; along with X-rays, Gamma rays, cosmic rays, along with many other phenomena, possibly even including (Billy-rays), OOPS sorry about that.

Early History of the Study of Galaxies:

A Persian astronomer, al-Sufi (903-36), is credited with first describing the spiral galaxy seen in the constellation Andromeda. By the middle of the 18th century, only three galaxies had been identified. In 1780, the French astronomer Charles Messier (1730-1817) published a list that included 32 galaxies. These galaxies are now identified by their Messier (M) numbers; the Andromeda galaxy, for example, is known among astronomers as M31.

Thousands of galaxies were identified and cataloged by the British astronomers Sir William and Caroline Herschel and Sir John Herschel, during the early part of the 19th century. Since 1900 galaxies have been discovered in large numbers first by photographic searches and by images from HST (Hubble Space Telescope). Galaxies at enormous distances from earth appear so tiny on a photograph that they can hardly be distinguished from stars. The largest known galaxy has about 13 times as many stars as the Milky Way.

In 1912 the American astronomer Vesto M. Slipher (1875-1969), working at the Lowell Observatory in Arizona, discovered that the lines in the spectrum of all galaxies were shifted toward the red spectral region. This was interpreted by the American astronomer Edwin Hubble as evidence that all galaxies are moving away from one another and led to the conclusion that the universe is expanding. It is not known if the universe will continue to expand or if it contains sufficient matter to slow down the galaxies gravitationally so they will eventually begin contracting to the point from which they arose. This is one of the driving forces and major problems behind the science known as Cosmology.

Classification of Galaxies:

When viewed or photographed with a large telescope, only the nearest galaxies exhibit individual stars. For most galaxies, only the combined light of all the stars can be detected. Galaxies exhibit a variety of forms. Some have an overall globular shape with a bright nucleus surrounded by a luminous structureless disk. Such galaxies, called (ELLIPTICALS), contain a population of old stars, usually with little apparent gas or dust, and few newly formed stars. Elliptical galaxies come in a vast range of sizes, from giant to dwarf.

In contrast, (SPIRAL GALAXIES) are flattened disk systems containing not only old stars, but also large populations of young stars, large amounts of gas and dust, and molecular clouds that are the birthplace of stars. The HST image of the "Birth-Place of Stars" in the Eagle Nebula, appears to bear this out according to the most recent theories. Often the regions containing bright young stars and gas clouds are arranged in long spiral arms that can be observed to wind around the galaxy. Generally a (HALO of faint older stars surrounds the disk; a smaller (NUCLEAR BULGE) often exists, emitting two jets of energetic matter in opposite directions.

Other disk-like galaxies, with no overall spiral form, are classified as (IRREGULARS). These galaxies also have large amounts of gas, dust, and young stars, but no arrangement of a spiral arm formation. They are most often located near the larger galaxies and their appearance is probably the result of a tidal encounter with the more massive galaxy, by either passing close to or actually going through another Galaxy. Some extremely (PECULIAR) galaxies are located in close groups of two or three, and their tidal interactions may probably have caused distortions of spiral arms, producing warped disks and long streamer tails.

(QUASARS) are objects that appear to be stellar or almost stellar, but their enormous red shifts identify them as objects that are at very large distances. They are probably closely related to radio galaxies and to BL Lacertae objects.

Determination of Extragalactic Distances:

As you view a galaxy with a telescope, it is impossible to gauge its distance, as it may be a gigantic bright galaxy at a large distance or a smaller fainter one closer to earth. Astronomers (estimate) distances by comparing the brightness or sizes of objects in the unknown galaxy with those in the earth's galaxy. The brightest stars, Type (1) one supernovas, star clusters, and gas clouds have been used for this purpose. Cepheid variables, stars the brightness of which varies periodically, are especially valuable because the period of pulsation is related to the intrinsic brightness of the star. By observing periodicity, the true brightness can be computed and compared with the apparent brightness; distance can then be (inferred). Recently astronomers have learned that the speed of the stars as they orbit the center of their galaxy depends on the intrinsic brightness and mass of that galaxy. Rapidly rotating galaxies are extremely luminous; slowly rotating ones are intrinsically faint. If the orbital velocities of stars in a galaxy can be determined, then the distance of that galaxy can be inferred.

Distribution of Galaxies:

Galaxies are generally not isolated in space but are often members of small or moderate-sized groups, which in turn form large clusters of galaxies. The earth's galaxy is one of a small group of around 31 confirmed galaxies that most astronomers call the (LOCAL GROUP). The earth's galaxy and the Andromeda galaxy are the two largest members, each with a million stars. The Large, Small, and Mini Magellanic Clouds are nearby halo satellite galaxies, but each is small and faint, with about 100 million stars.

The nearest cluster is the Virgo cluster; the Local Group is an outlying member of the cluster, which contains thousands of galaxies of all types. They all share a common direction of motion, the cause of which might be a supercluster hidden from view by our own galaxy, since superclusters up to 300 million light-years across are known. Some theorists suggest instead that a cosmic "string" a one-dimensional flaw in the fabric of space-time, could be the cause.

Overall, the distribution of clusters and superclusters in the universe is not uniform. Instead, superclusters of tens of thousands of galaxies are arranged in long, stringy, lace-like filaments, arranged around large voids. The Great Wall, a galactic filament discovered in 1989, stretches across more than half a billion light-years of space. Cosmologists theorize that "dark matter," a hypothetical material that neither radiates nor reflects light, has sufficient mass to generate the gravitational fields responsible for the heterogeneous structure of the universe.

The most distant galaxies known, near the edge of the observable universe, are faint blue objects called "blue fuzzies" because of their appearance on photographic plates. The images were obtained by aiming a telescope at apparently blank regions of the sky and using a solid-state charge-coupled detector (CCD) to gather the very faint light, then processing the images by means of a computer. The galaxies, moving away from earth at about 88 percent of the speed of light, may have been formed about 2 billion years after the origin of the universe.

Rotation of Spiral Galaxies:

Stars and gas clouds orbit about the center of their galaxy. Orbital periods are usually more than 100 million years. These motions are studied by measuring the positions of lines in the galaxy spectra. In spiral galaxies, the stars move in circular orbits, with velocities that increase with increasing distances from the center. At the edges of spiral disks, velocities of 300 km/sec (about 185 mi/sec) have been measured at distances as great as 150,000 light-years.

This increase in velocity with increase in distance is unlike planetary velocities in the solar system, for example, where the velocities of planets decrease with increasing distance from the sun. This difference tells astronomers that the mass of a galaxy is not as centrally concentrated as is the mass in the solar system. A significant portion of galaxy mass is located at large distances from the center of the galaxy, but this mass has so little luminosity that it has only been detected by its gravitational attraction. Studies of velocities of stars in external galaxies have led to the belief that much of the mass in the universe is not visible as stars. Its exact nature is unknown at present.

Radiation from a Galaxy:

Knowledge of the appearance of a galaxy is based on optical observations. Knowledge of the composition and motions of the individual stars comes from spectral studies in the optical region also. Because the hydrogen gas in the spiral arms of a galaxy radiates in the radio portion of the electromagnetic spectrum, many details of galactic structure are learned from studies in the radio region. The warm dust in the nucleus and spiral arms of a galaxy radiates in the infrared portion of the spectrum. Some galaxies radiate more energy in the optical region.

Recent X-ray observations have confirmed that galactic halos contain hot gas, gas with temperatures of millions of degrees. X-ray emission is also observed from objects as varied as globular clusters, Type (1) and (2) supernova remnants, and hot gas in clusters of galaxies. Observations in the ultraviolet region also reveal the properties of the gas in the halo, as well as details of the evolution of young stars in galaxies.

In the days and months to come HST will provide the most information ever acquired about the structure of galaxies and the Universe in general, along with all the new breeds for space and ground born telescopes and instruments yet to come.

*** Astronomy Dictionary ***

LOCAL GROUP: This group of galaxies is around 3 million light years in diameter and has a total mass estimated at 3 to 5 x 10 to the 12 solar masses. The three brightest members are Andromedia, Milky Way, and M33.

>>> From The Cargo Bay <<<

The final question in our flight is: At what speed does the Orbiter (glider) land at? The transition from (RSC) Reaction Control System to Aerodynamic control system happens in several stages or steps. 1st) As the entry begins, the forward maneuvering thrusters are inhibited. 2nd) The aft thrusters are used until the dynamic pressure of 10 psi) pounds per square inch are recorded by onboard computers, at which time the aft roll thrusters are inhibited and the ailerons are now effective. 3rd) At a dynamic pressure of 20 psi the aft pitch thrusters are inhibited and the elevators begin their function. 4th) Last at a speed of Mach 3.5 and around 45,000 feet, the aft yaw thrusters are inhibited and the rudder is now used. 5th) At an altitude of 90 feet the landing gear extend, at 14 seconds before touchdown. Immediately the final flare is made to reduce the airspeed to 215 mph at which time the landing is made at a little slower speed.

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.)


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:

29 October

19 November

17 December



That’s all folks…