ASTRONOMY CLUB OF TULSA

January 2001

Friday, January 12, 2001 at 7:30 PM

IF TULSA SCHOOLS ARE CLOSED ON JAN 12, OUR MEETING WILL ALSO BE CANCELED.

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.

John Land

Our apologies on canceling the Dec 15 meeting due to weather. We posted it on the web site and our message-line at 688-MARS. We requested TV stations to post information, but only Channel 6 was willing to do so. We hope to reschedule our Space Art program in the spring. Future meetings: We will be trying something new this year to schedule meetings. The first Friday of each month lies near the Full Moon so our meetings will be held at TU on Feb 2, Mar 2, and April 4, May 5 and June 1. Again we may make changes if special opportunities occur. January 12 Topic: Getting the most out of your telescope. We will be sharing ideas related to observing with telescopes. Traditionally, members share new astronomy equipment and accessories they may have received for Christmas. We will also share some tips for using your telescope in cold weather. We will be glad to try to answer questions you may have about telescopes.

Denny Mishler will bring his new Celestron Nexstar 8. This is one of those fully equipped GOTO telescopes we all wish Santa had left under the tree!! Gary Buckmaster will be demonstrating his H-Alpha solar filter that some of us enjoyed seeing this summer. These are the filters that let you see those awesome prominences looping off the edge of the sun. We will be looking forward to other club members sharing their new astronomy treasurers.

Missed the Christmas Eclipse? There are some great images of the eclipse at http://www.spaceweather.com/eclipses/gallery_25dec00.html 

Attention: LARGE SUNSPOT GROUP VISIBLE. There are some huge sunspot groups on the sun lately. Whenever sunspots exceed 40,000 miles in diameter they can be seen without magnification. (These are 5 or more times the Earth's Diameter) A nice group was visible prior to the Christmas blizzard and a new group, 9289, promises to exceed the previous group as we enter the New Year. The sunspots will look like a small "freckle" on the sun. Daily solar photos are visible at www.spaceweather.com. These will help you determine where to look on the sun.

CAUTION!! You must have a certified safe solar filter to view the sun. The eclipse glasses many purchased to view the eclipse will allow you to see these large sunspot groups safely. Small green filters that screw into a telescope eyepiece are NOT SAFE. They can overheat and burst. Telescope Solar filters must fit on the front of the telescope, keeping the excessive light out of the light path.

We have some great astronomy opportunities coming up in January and February. Broken Arrow school system is hosting Dr Jeff Goldstein and the Windows to the Universe team again this year during the week of Jan 9 to 12. Two public speakers forums will be free to the public.

On Tuesday, Jan 9th, Dr. Tim Livengood will present "The ABC's of Comets" at 7:00 PM at Broken Arrow North Intermediate High. NIHS is located south of the BA Expressway at the Lynn Lane exit, 1/2 mile south of Kenosha. Dr Tim is a specialist in planetary and comet atmospheres. Last year he did a live teleconference from the deck of the 10-meter Keck II telescope on Mauna Kea, Hawaii.

Thursday night at 7:00 PM at Union McAuliffe Elementary school, located about 6515 South Garnett, Dr Jeff Goldstein will present "Saying Hi to E.T. on a planet Far Far Away". Jeff is an astrophysicist who directs the Challenger Center team. Dr Jeff also works on the Huygens probe due to land on Saturn's moon Titan in July of 2004. The Huygens probe is part of the Cassini Mission to Saturn that just got a big gravity boost as it past Jupiter on Dec 30, 2000

Shawn Jackson, Physic/Astronomy professor at TU, invites us to join TU for some exciting speakers in February. Shawn would like to invite the Astronomy Club of Tulsa to hear our distinguished guest speaker who will visit TU Feb. 28 and March 1, 2001.

He is Dr. Fritz Benedict of the University of Texas McDonald Observatory. He will deliver the lectures listed below. I want to extend a special invitation to the Astronomy Club of Tulsa members to attend all three lectures in general but particularly the Shapley Lecture (Wednesday evening). Please invite your students and any one else who might like to attend these lectures...free of charge!

Speaking schedule for Dr. Benedict

1. Wednesday, Feb. 28, 2001. 11:00 a.m. KEP M2, "Playing Hide and Seek with the Universe" (Cosmology and hidden mass). Audience: A no-prerequisite astronomy class open to all students.

2. Wednesday, Feb. 28, 2001. Shapley Lecture. 7:00 p.m. KEP M1, "Nine Steps to Extraterrestrial Life" (astrobiology). Audience: The general public.

3. Thursday, March 1, 2001. 11:00 A.M. KEP M2, " Finding Almost Planets and Almost Finding Planets" (his own research with the HST to locate extrasolar planets). Audience: This is a technical talk aimed primarily at the students and faculty of the College of Engineering and Natural Sciences.

For those of you who have been yearning for some big name speakers, your prayers have been answered! Lets see a good representation of support from our club.

Time to pay your Club DUES. Memberships are $25 per year regular or $15 per year student. You must be actively enrolled in High School or College to qualify for student rate. As a member you will continue to receive our club newsletter and opportunities to participate with us in our activities. You will also receive a free subscription to the Astronomical League's Reflector newsletter and discounts on League materials. Discounts are also available for subscriptions to the two leading Astronomy periodicals. Sky and Telescope is $30 /yr and Astronomy magazine is $29. Don't miss out on the great stories for 2001.  Send your checks to our treasure Nick Pottorf at 3832 S Victor, Tulsa OK 74105.

Astronomy Club Shirts: Aaron Coyner has designed some nice looking astronomy club shirts with our club logo and name embroidered on the front. They are short-sleeved Polo Type collared shirts in a 60/40 blend. He is taking orders for them at $17.00 each.  Contact him at 918.259.8757.   

We are getting lots of calls for groups to visit the observatory or for us to come to schools with our telescopes. Most of these groups make generous donations toward the expenses of our observatory. Please contact Gerry Andries and confirm your commitment to help with these events.  Contact - Gerry Andries - Phone or < Gerry Andries e-mail >

The following is the current schedule of star parties and public groups.  All events are at the RMCC unless noted otherwise:

How "Observant" are you?

As a group who like to "observe", how many of you observed an Astronomy Club of Tulsa  member in the January issue of Sky & Telescope wearing an ACT t-shirt?

January SKY FORUM

By Don Cole

Let us start off this new year (and by the way HAPPY NEW YEAR 2001 TO YOU ALL) by looking at some different types of star formations or groupings, such as:

Galaxies are massive collections of hundreds of millions of stars, all gravitationally interacting, and orbiting about a common center. All the stars visible to the unaided eye at night 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; and cosmic rays.

The 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 by photographic searches. 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 (see Red Shift below). 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.

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 is 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 some old stars but also large populations of young stars, much gas and dust, and molecular clouds that are the birthplace of stars. 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 form. They are usually located near larger galaxies, and their appearance is probably the result of a tidal encounter with the more massive galaxy. Some extremely peculiar galaxies are located in close groups of two or three, and their tidal interactions have caused distortions of spiral arms, producing warped disks and long streamer tails.

Quasars are objects that appear stellar or almost stellar, but their enormous red shifts identify them as objects at very large distances (see Quasar below). Most astronomers now believe that quasars are active galaxies whose nucleii contain enormous black holes. They are probably closely related to radio galaxies and to BL Lacertae objects.

In viewing a galaxy with a telescope, inferring its distance is impossible, for it may be a gigantic galaxy at a large distance or a smaller 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, 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 about 20 galaxies that astronomers call the Local Group. The earth's galaxy and the Andromeda galaxy are the two largest members, each with a million million stars. The Large, Small, and Mini Magellanic Clouds are nearby 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 many types. They all share a common direction of motion, the cause of which might be a super cluster hidden from view by our own galaxy, since super clusters 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 super clusters in the universe is not uniform. Instead, super clusters of tens of thousands of galaxies are arranged in long, stringy, lacelike 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.

Rotation of Spiral Galaxies

Stars and gas clouds orbit about the center of their galaxy. Orbital periods are 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, 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.

*** Astronomy Dictionary ***

RED SHIFT: A shift toward longer wavelengths observed in the lines of spectra of celestial objects. The American astronomer Edwin Powell Hubble, in 1929, linked the red shift observed in spectra of galaxies to the expansion of the universe. Hubble theorized that this red shift, called the cosmological red shift, is caused by the Doppler effect and hence indicates the speed of recession of the galaxies-and, by using Hubble's law, the distances of the galaxies.

QUASAR: An acronym for quasi-stellar radio source, any of the blue, star like objects that are strong radio emitters and the spectra of which exhibit a strong red shift. Quasars were identified as sources of intense radio emission in the late 1950s. In 1960, using the 200-in. (508-cm) telescope on Mount Palomar in California to observe the positions of these radio sources, astronomers discovered objects the spectra of which showed emission lines that could not be identified. In 1963 the Dutch- American astronomer Maarten Schmidt discovered that these unidentified emission lines in the spectrum of quasar 3C 273 were known lines that exhibited a far stronger red shift than in any other known object.

One known cause of red shift is the Doppler effect, which shifts the wavelength of emitted light of celestial objects toward the red (longer wavelengths, see above) when the objects are moving away from the earth because of the expansion of the universe. This red shift is called cosmological, and from the amount of red shift astronomers can calculate the recession velocity. Hubble's law, which states that recession velocity caused by the expansion of the universe is directly proportional to the distance of the object, indicates that quasar 3C 273 is 1.5 billion light-years from the earth.

QUIZ QUESTION: Do you think you could find and observe 3C 273? If so where in the sky and what time of the year could it be viewed?

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.) "Microsoft "Encarta"

On Wed, 13 Dec 2000, Miho Rahm <mihorahm@uclink4.berkeley.edu> wrote:

Hands-On Universe

Dear Astronomy Enthusiast:

We want to explore with you a way in which we can collaborate. The Hands-On Universe Project (HOU) is a novel and innovative astronomy education program supported by the National Science Foundation. HOU enables students to investigate the universe while applying tools and concepts from science, math, and technology. High school teachers and students are provided image processing tools, data in the form of CCD images, and the skills needed to conduct basic astronomy research. In analyzing this data, students throughout the United States, Sweden, Japan, Germany, France, Italy, Senegal, and Australia are given the opportunity to explore astronomical projects together. Please visit our website for further details.

Hands-On Universe has experienced great success in past years. In 1994 two of our students from Oil City, Pennsylvania provided some of the earliest supernovae data on record with their images of SN 1994I in the Whirlpool Galaxy. In 1998 two of our students in Northfield, Massachusetts discovered Kuiper Belt Object 1998FS144 through the Hands-On Universe Asteroid Search. Although these have been our most prominent success stories, there are many day-to-day examples of students and teachers who have been turned on to astronomy through HOU as well.

At this point Hands-On Universe is working to establish one of the first global networks of robotic telescopes available to high schools. While this plan continues to go through its research and development phases, we are finding a strong need for new data and individuals who would be willing to work with teachers throughout the country to acquire this new data. It is for this reason that we are seeking your help.

Members of amateur astronomy organizations not only have a wealth of experience and equipment, but also the common goal of sharing the wonder of our universe with others. HOU is seeking the help of skilled amateur astronomers nationwide who would be willing to work with our teachers. Over the past seven years HOU has been training teachers in basic astronomy research skills. We would be asking that individual amateurs or groups work with these classroom teachers to provide CCD images, observing tips, and other astronomical resources. In return, Hands-On Universe will make its image processing software available, and provide access to our large image archive and other web resources.

Please pass this letter on to those in your organization who would be interested in becoming part of the Hands-On Universe Amateur Astronomer - Education Outreach Network. Participating amateurs or professionals will be listed at our website, and contacted by teachers in their region for assistance. Any interested amateurs should sign up on the HOU website.

In addition, if you know of any teachers in your region who may be interested in HOU training, please direct them to our web site for our professional development opportunity funded by National Science Foundation.

Thank you so much for your time and consideration. If you have any further questions please feel free to contact Dr. Carl Pennypacker at (510) 486-7429 or send e-mail to pennypacker@lbl.gov. We look forward to having you as part of our astronomy education team.

Sincerely,

Carl Pennypacker
Hughes Pack
Tim Spuck
HOU Project Co-Director
Astronomy Educator
Region Astronomical Society

Miho Rahm
Project Manager
Hands-On Universe
Lawrence Hall of Science #5200
University of California
Berkeley, CA 94720-5200

Email: houstaff@hou.lbl.gov

Voice (510) 642-0552
FAX (510) 642-1055

Astronomy Club of Tulsa, 918.688.MARS

President: John Land

Vice President: Dennis Mishler

Secretary: Teresa Kincannon

Treasurer: Nick Pottorf

RMCC Observatory Manager: Gerry Andries

Observing Chairman: David Stine

Web Master: Tom McDonough

New Membership: Dennis Mishler

Librarian: Ed Reinhart

Education Coordinator: Scott Parker