February 2009 - Volume 38, Number 2

MEETING NOTICE: There will be a special meeting of the BARNARD ASTRONOMICAL SOCIETY on Thursday, February 12 th at the Challenger Space Center at 855 E. 5 th Street , Chattanooga , TN. There will be a tour and a mini mission, beginning at 7:00 pm .

 

The Barnard STAR is the official publication of the Barnard Astronomical Society.

Planned Activities to Enjoy The Wonders of Astronomy—
Celebrating Amateurs Who Are Professional in Knowledge

“Giving amateurs their due: The term ‘amateur' is often used negatively as a synonym for ‘unskilled.' Not here! In astronomy, the word remains true to its Latin root, amator, meaning ‘lover.' Amateur astronomers spend countless hours under the starry sky purely for the love of it. Many become as skilled at telescope observing or astrophotography as any professional—often more so.”

Discovering the Joy of Astronomy

“The joy of astronomy comes from finding your way around the starry sky and understanding what you see.” –The Editors, SKY AND TELESCOPE MAGAZINE

 

Mourning the Increasing Loss of Dark Night Skies in Our Cities

“There is no more important task for the modern amateur astronomer than to fight the steady growth of light pollution in urban areas. Already we are witnessing the tragedy of the first generation of city children who might never see the beauty of a dark night sky.”

--Director, Observatory, Houston Museum of Natural Science.

Note: BAS endorses outdoor lighting restriction efforts by the International Dark Sky Association (IDSA) and also by local organizations such as Save Roane Starry Skies (SRSS) at The Tamke-Allan Observatory, Roane State College, Harriman , TN.

 

Technical Areas of Specialization within BAS for Member Participation

Large Aperture/Dark Sky/Deep Space Optical Astronomy at Several Regional Dark Sky Sites
For more information, contact David Witt or Victor Rogers.

Astrophotography
For more information, contact David Hanon or Dr. Gary Caldwell

Radio Astronomy at a Fully Functional Radio Telescope Observatory Outside of Cleveland , TN
For more information, contact Bill and Melinda Lord, Bill Seymour, or John Mannone.

Sidewalk Astronomy—“Chattanooga Out of This World” Challenging Optical Viewing of The Earth's Moon and The Inner Planets for the General Public from Downtown Locations Surrounded By Bright City Lights
For more information, contact Tom Adkins or Joe D'Agostono

 

BAS January Meeting

For approximately 40 BAS members and guests, the special “Rocks from Space--Meteorites” program at the Northgate Community Center on January 17th was indeed special. The presenter, Dr. Fritz Kleinhaus, Professor Emeritus of Physics at Indiana and Purdue Universities , blended a witty and down-to-earth style with a large display of actual ”rocks from outer space.” These ranged from the size of a marble to a small loaf of bread and filled many tables in the meeting room. A colorful PowerPoint presentation illustrated the many interesting parts of the program.

While the word “meteoroid” generally describes a small, solid body traveling through outer space, the term “meteorite” is defined as that part of a meteoroid which enters the Earth's atmosphere and survives to impact the Earth's surface.

Meteorite fragments which strike the Earth have come from numerous places in outer space but are generally thought to originate from within the Solar System. A prominent source is the asteroid belt, between the orbits of Mars and Jupiter, possibly a proto-planetary disk that never coalesced into a planet. In recent years, careful geological investigations have suggested the Earth's moon and the Planet Mars are also sources of some meteorites, as secondary ejecta from direct hits on those bodies is pulled into the Earth's gravitational field.

How do we know that these rocks are really from outer space? This is one of the first questions in the mind of many persons who attend this type of presentation. The answer is that careful scientific investigation establishes several lines of evidence to support extraterrestrial origins—including dissimilar chemical and geological makeup from “earth rocks”; and the extreme age of the space rocks through radiological decay dating (such as Uranium to Lead, and Potassium 40 to Argon); the oldest space rocks are up to 4.6 billion years old vs. only 2 billion years old for Earth rocks.

In the last 25 years, refined trajectory calculations have verified that at least five large meteorites, including the Peekskill (NY) bolide of 1992, originated in the asteroid belt.

There are three main categories of meteorites:

1. IRONS—Black in color; high concentration of Iron with 3-16% Nickel. This is the type most frequently found on Earth.

2. STONES—Mostly stone but enough Iron to be attracted to a magnet. There are many examples from The Sahara in NW Africa where American entrepreneurs in the lucrative collection business have equipped nomadic camel drivers inexpensive magnets from Edmund Scientific. (The world-wide demand is lucrative for both collectors and camel drivers.) As opposed to a densely forested region of the Earth where a meteorite falling to the ground may be hidden from view, a meteorite laying in the desert sand is usually more visible. Many STONES have variations of brown colors from exposure to sunlight, heat, and sand; STONES are the type of meteorite to most frequently fall from space, but most burn up in the atmosphere before striking the ground.

3. STONY IRONS—Very rare but very pretty; Iron-Nickel matrix with Olivene (common mineral on Earth) flecks.

Dr. Kleinhaus spent a considerable amount of time discussing significant meteorite impacts on Earth. These ranged from the grapefruit size object that destroyed the back end of an unoccupied Chevrolet parked in a driveway in Yonkers, NY; to the kilometer size rock that struck the Yucatan Peninsula in Mexico 65 million years ago resulting in a sudden climate change that killed the dinosaurs and many smaller mammal species.

BAS members have visited some of the large impact craters that were discussed. The 50,000 year old Canyon Diablo Crater (also known as The Great Meteor Crater) in Arizona is 4,000 feet across and 400 feet deep. The Odessa Crater in Texas is 600 feet in diameter, was originally100 feet deep, but is now only 6 feet deep. In Tennessee , shatter cones (Earth rock stressed by the shock of impact) have been brought back from the Wells Creek Site (12 km diameter; 200 million years old) by BAS collectors.

Also tektites (glassy Earth materials which have been melted by a meteorite impact and thrown back up into the air) have been collected.

Flynn Creek (3.8 km diameter; 360 million years old) is another prominent meteorite crater in our state. And, a NASA satellite has recently identified a third large crater, previously unknown, in Tennessee .

Oxidation (rust) on the surface of meteorites occurs continuously due to the high iron content and is a constant problem for collectors.

“Hands-on” is an important part of Dr. Kleinhaus' presentations. He passed to the audience investigation kits containing a small magnet and various samples to evaluate. Also, he invited attendees to examine the dozens of varied meteorite specimens on display.

As with most commercial ventures, the business of collecting meteorites has its share of dishonest persons and scams. For further reliable information, a reputable web site is meteoritemarket.com. For persons who might be interested in further reading on the subject, Dr. Kleinhaus recommends the following book: Rocks from Space; 2nd Edition; O. Richard Norton

Thanks to the BAS Program Committee for arranging this outstanding Program.

 

The Basics
Telescope Optical Path Parameters

Light Gathering Power

The telescope's ability to reveal faint objects depends mainly on the size of its primary objective—a lens or mirror 3 inches in diameter will gather two times as much light as a 2 inch, and a 6 inch will gather four times as much as a 3 inch.

Diameter of Primary Objective (Inches)	Faintest Apparent Visual Magnitude Visible	Approx. No. of Stars Visible
4 ¼	12	2,270,000
7	13	5,700,000
12 ½	15	32,000,000

Magnification

The eyepiece bends the light rays so they form a larger image in the retina of the eye than would be formed if no eyepiece were used. The size of the image depends on the focal length of the eyepiece—the distance between the eyepiece and the point at which the converging light rays meet. The shorter the eyepiece focal length, the larger the image. Typically, focal lengths range from ¼ inch to ! ½ to 2 inches for eyepieces.

Magnification also depends on the focal length of the objective mirror or lens. The longer the focal length of the objective, the greater the magnification in combination with a given eyepiece.

To determine the actual magnification, divide the focal length of the eyepiece into the focal length of the objective. For example, if the focal length of the objective is 50 inches, a ½ inch eyepiece will give 100 power (”100X”). However, there is an upper practical limit of approximately. 50 times the diameter of the objective in inches. This means about 150X for a 3 inch telescope or 300X for a 6 inch.

Resolving Power

The resolving power of an instrument is its ability to show the fine detail—for example, markings on planets. To determine the theoretical resolving power of an objective, divide the number 4.5 by the diameter of the objective in inches. The answer (known as the “Dawes' limit”) is the distance, in seconds of arc, between the closest objects that can be distinguished. A good 3 inch lens should separate objects about 1.5” (seconds) apart. One second of arc is 1/60' (minute) or 1/3600 degree. A degree is 1/90th of the distance from the horizon to the zenith (point in the sky directly overhead). The average unaided human eye, under good conditions, can distinguish stars that are about 180” apart.

Focal Ratio (f number)

The focal length of the objective divided by the aperture. The lower the f number, the wider the field of view of the telescope, but its magnification will also be weaker. Focal ratios below f/8 are best suited for astrophotography of large areas of the sky. Mid range (f/8 to f/11) focal ratios are good for observing galaxies, nebulae, and star clusters. Focal ratios larger than f/12 are more suited to planetary work and splitting close double stars, for they have low image brightness and small fields of view.

References

1) Star Hopping ; Robert Garfield
2) The Sky Observer's Guide ; R. Newton Mayall, Margaret Mayall, and Jerome Wyckoff

 

Respectfully submitted by Bill Seymour, BAS Secretary.

 

Mark Your Calendar

Here are a few of the upcoming meetings that have programs scheduled:

February 12 7:00 PM : Challenger Space Center Tour and Mini Mission

Directions: http://www.utc.edu/Outreach/ChallengerCenter/Directions.htm

E-mail Dr. Gary Caldwell at botecap@comcast.net so he can add you to the mission manifest. It is important we give the center a fairly accurate number. The program will last about 2 hours.

March 12: Show & Tell- Bring something you have built for your astronomy habit or bring your one astronomy gizmo you can not live without. If you have something you bought that was a bust, bring it to share with the club. This will be an informal program that should be a lot of fun.

April 9 : Dr. Chuck Higgins, Professor of Physics & Astronomy at MTSU
"Jupiter and Her Satellites: Radio Connections"

October 8 : Joint Meeting with the Chemical Society, Prof. John Mannone will present a program of interest to both astronomers and chemists.

December 5 : Annual BAS Christmas Party

Star Parties

April 17 : Boy Scout Camporee at Camp Columbus , Contact David Witt
This annual event is fun for the scouts and members so plan to bring your telescope or binoculars.

 

BAS members and friends,

 We will have the annual Star Party for the Boy Scouts on Friday, April 17, 2009 at Camp Columbus . The moon will be at last quarter, and Saturn will be a visible in the evening. More details and directions to the camp will follow as the time nears. There will be hundreds of Boy Scouts there, so please plan now to help by bringing a telescope if you can, to share the wonders of the night sky with the Scouts.

David Witt

Pictures from the Meteorite Presentation

	The audience looks on as Dr. Fritz Kleinhans explains where meteorites come from and their composition.
	Dr. Fritz Kleinhans talks with Dr. Bob Marlowe after his presentation.
	Bobby Thompson and Dr. Bob Marlowe look at one of the many meteorites Dr. Kleinhans passed around to the audience.
	BAS members and guests had an opportunity to look at the many specimens Dr. Kleinhans has collected over the last several years.
	Dr. Fritz Kleinhans

 

 

Strings and Things

String theory (also termed "superstring" theory) is a mathematical attempt to describe all fundamental forces and particles as manifestations of a single, underlying entity, the "string."

String theory's predictions are consistent with all known experimental data, and it is felt by some physicists to be a candidate for the long-sought "theory of every thing" (i.e., a single theory describing all fundamental physical phenomena); however, string theory has proved difficult to subject to definitive experimental tests, and therefore actually remains a speculative hypothesis.

Physics was defined before the twentieth century, "classical" physics, envisioned the fundamental particles of matter as tiny, solid spheres. Quantum physics, which originated during the first 40 years of the twentieth century, envisioned the fundamental particles simultaneously as particles and as waves; both mental pictures were necessary to make sense out of certain experimental results.

String theory, the first forms of which were developed in the late 1960s, proposes that the fundamental unit of everything is the "string," pictured as a bit of taut wire or string on the order of 10 -33 cm in length (a factor of 10 -20 smaller than a proton. These strings may be "open," like a guitar string, or form loops like rubber bands. Also, they may merge with other strings or divide into substrings.

Beginning a few years after its initial formulation, string theory stagnated for a decade because of mathematical difficulties, but exploded in the 1980s with the discovery that the theory actually possesses a highly desirable mathematical feature termed E(8)×E(8) symmetry. Several major theoretical victories were won by string theorists in the 1990s, and intense efforts to extend string theory continue today. String theory is not the product of a single mind, like the theory of relativity but has been produced by scores of physicists refining each other's ideas in stages.

But now, after all this effort to put all the particle physicists out of business we must again ask is it 'good science' if one cannot design a 'Falsification" experiment to test it? I for one do not even know what a String./ Particle /Wave might look like in the 'Classical Sense' Perhaps my old fashioned thinking will never catch up to this. Indeed I'm old and searching for excuses!

Good Seeing!

 

DIRECTIONS TO ORION ACRES

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.

 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

 

Start Your Own Meteorite Collection

Through a special purchase arranged by the University of The South , BAS has obtained a large meteorite collection at an unusually low price per gram. These meteorites will be offered for sale to BAS members at the August 14th meeting as a fund-raiser for the Club treasury.

The unclassified North West Africa (NWA) EL3 meteorites have been individually bagged with the weight and magnetic strength noted for each one. There is a wide selection of sizes and the price will be very affordable.

Can 't make it to the meeting? You can place your order with Bill & Melinda Lord at ap_guardian@yahoo.com or 423-478-9043. The price is just 10 cents per gram, and add $5.00 for shipping and handling.

 

TELESCOPES WANTED

We want everyone in our club to have access to a great telescope. Our plan is to refurbish telescopes so that we can loan them to astronomers without scopes of their own. I f you have a telescope or accessories you are no longer using, please let us have it. We promise someone will use it and treat it with care and respect. Of course you can have a receipt for your tax write-off and every penny is welcome if you would like to donate money so we can buy or fix up a telescope.

Contact Gary Caldwell, Adam Krause or Bill Lord if you have a donation, we will happily come to your door to pick up your unwanted telescope. Sponsorship information will be posted on the web and in the Barnard Star.

 

BAS WEB SITE
http://bas.chattanooga.net

 

Officers

President……………………………………….... Gary Caldwell
Vice-President………………………………………….Bill Lord
Secretary…………………………………...………Bill Seymour
Treasurer………………………………………….Melinda Lord
STAR Editor……………………………………….Steve Ramey
Webmaster…………………………………………….Rod Ruch
Star Party Chairman…………………...…………...Victor Rogers
Outreach Coordinator………………...…………...John Mannone
Program Committee Co-Chairs…...... John Mannone and Bill Lord
Member-at Large………………..……………………David Witt

 

January Minutes

A BAS business session was not held in January due to the Northgate Community Center Program which took the place of the regular Jones Observatory meeting.

 

REMINDER- Your annual BAS dues of are now due on the anniversary of your membership in accordance with the adopted amendment to the by-laws. The due date appears below your name on the address on the front of this newsletter. If your expiration date says “Overdue” or if you don't agree with the date shown, contact Melinda Lord to resolve discrepancies. The current dues rates 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:

Melinda Lord
354 N West Cir NW
Cleveland , TN 37312-1011

Along with the group subscription rate of $32.95 for Sky and Telescope, or $34.00 for Astronomy. Note the increased rate for Astronomy. This was effective July 31, 2005

 

DEADLINE- All articles and other materials for publication in the next STAR are due no later than Wednesday, March 4 th . The following media are acceptable: hard copy, disk (IBM), video tape (VHS), prints, or e-mail to bas@chattanooga.net or s tramey@catt.com and attach a file or mail to:

Steve Ramey
109 Sioux Trail
Ringgold GA 30736

PHOTOGRAPHS ARE ALSO ACCEPTABLE.