February/March 2001 Issue

From the President's Desk

by Richard Greiner

With winter setting in hard this year, I have not personally gotten in much astronomy. But I am happy to see that a number of our members have done a great deal. At the January meeting we had a presentation by John Rummel, Mike McDowell , and Greg Sellek, each of whom showed us the result of their astro photography with film and CCD cameras.

John and Mike showed a number of excellent film images ranging from aurora to nebula. Their discussions of techniques impressed me and I am sure showed others "how to." Members seemed impressed and appreciative of this presentation judging from the good questions during and the extended discussions after the presentation. Greg Sellek managed to get several images of asteroids using a CCD camera which were good enough to earn the MAS an observatory number registered with the IAU: Minor Planet Center. It is exciting to see our members using the MAS facilities, demonstrating their fine imaging capability and teaching others how to take these interesting images.

I am pleased to say that at the January 12 meeting we have also approved the new set of by-laws, essentially unchanged from those you received with the newsletter last time. The MAS is now legally up to date and with regulations that fit the facts of how we operate.

We have started a new tradition of having coffee, cookies and other refreshments at the regular meetings. The turnout for the January meeting was over thirty people. We also picked up several additional members at this meeting and now stand at about 85 members. This is a healthy number, since we have the manpower to make working events easier for everyone. I look forward to additional joint member activities in the months to come. As spring rolls around, which it eventually will, we have a program of expanded activities planned for our dark site and activities with the public. Excellent guest speakers are lined up for our regular meetings. I invite everyone to join us on all possible occasions to participate in and enjoy MAS events.
 
 

Minor Planet Astrometry at YRS

by Greg Sellek

The last few months have been very interesting for me at YRS. In addition to my attempts at using the LX200 under computer control, I started playing around with a CCD camera. Doc Greiner had graciously loaned me an ST-7E, and I quickly learned that CCD imaging was not as easy as I had imagined.

After spending several weeks imaging everything I could possibly try to take a picture of with the CCD, I decided to see what an asteroid would look like. So, I aimed the scope to the position where one was supposed to be and snapped off a frame. Then about twenty minutes later, I went back and re-imaged the asteroid. Sure enough, it was very obvious which 'star' was the asteroid since it had moved against the background stars. I was hooked.

I have always had a desire to contribute something to the scientific community, but never thought that I would have the expertise (or patience) to do so. After reading a few articles on minor planet hunting, I realized that this is something that could be done at YRS! The LX200 is almost perfectly suited to this type of observing, and the Doc G. observatory is already wired to the clubhouse. With a few extra wires and some electrical tape, we were in business.

There are three main computer programs that I found useful for doing minor planet observations. Astronomer's Control Panel (ACP) allows both manual and automated control over the LX200, while Maxim DL does the same for the CCD camera. Finally, Pinpoint is used to obtain astrometric measurements.

Observations can be made manually or automated. Using VBScript, you have the ability to program virtually any function of the scope, camera, or pinpoint into an automated script. A sample script illustrates one of the great advantages of Pinpoint, the ability to accurately point your telescope without the use of T-Point! By taking a short exposure with the CCD camera, Pinpoint can make an astrometric measurement of the center position of your CCD image. It then takes those coordinates and synchronizes the telescope to the new 'real' coordinates. This process can be repeated as often as necessary to make sure that scope is pointed exactly where it is supposed to be. By providing this same script with a list of objects, it can accurately slew the telescope and image them for you.

By utilizing the programs listed above, I was able to make manual observations of two minor planets in early January. The results of those observations were sent into the Minor Planet Center (MPC). Upon confirmation of the measurements, we (MAS) were issued an official observatory number for YRS. This gives us the ability to do real research with the LX200. We could even discover our own asteroid!

This image was one of several used to submit data to the MPC. The arrow has been added to indicate the asteroid. 5751 Zao, Distance from Earth: 0.878693 AU, Distance from Sun: 1.524593 AU, Magnitude: 16.9

I am currently in the process of perfecting the methods and equipment for making such observations. I would welcome the opportunity to help get others involved in this project, as I would like to make it a club effort. For more information, please contact me at orion98@home.com or call me at 848-6301.
 
 

Space Camp, Univ. of Arizona, 2001

by A.J. Carver

Many people have seen the night sky from a dark site. The milky way trailing across the sky, too many stars to count. But most of us only get the chance to do this for a period of an evening or maybe a weekend, if we're lucky. Imagine seeing the night sky at over 9,000 feet in a desert mountain range for a whole week. Sounds like a dream to most of us. But it is reality with the University of Arizona astronomy camp. Students get a week to have adventures in astronomy in one of the two camps, beginning and advanced, with others who share their interest. These adventures aren't restricted to laying on your back looking up. Campers use research grade telescopes, including a 40", 60", and 61" telescopes in the Catalina mountains outside of Tucson Arizona. CCD cameras, spectrographs and other special equipment is available for campers use.

During the day campers travel to astronomy related areas around southern Arizona, Kitts Peak, the UA mirror lab, Tucson Planetarium, and more. They also have the opportunity to learn from experienced counselors. I had the fortune of having counselors who were working in CCD labs, teaching college courses, running observatories, earning their PhDs , working with NASA, and most importantly who wanted to be there.

The teen camp is open to students ages 13-19. Special exemptions are possible through the camp director. Adults, don't feel left out. There are also camps for adults it is not as long but I imagine just as exciting. The camp is well priced for the experience. With financial aid available it is in the reach of just about anyone. It was my experience getting to the camp was more expensive than the camp itself.

How does one learn more about this possibility? First go to the MAS website. Click on "links," and there you will find UA Astronomy Camp - as reported by this writer. There you will find application information, more detailed equipment lists, history of the camp and its graduates, and more. If this sounds interesting to you then hurry. Get to the website and learn more. On January 8, 2001 the beginning camp was 45% full and the advanced camp was 20% full. About 26 students are selected for each camp. Selections are made early each month until the camps are full. So decide quickly and apply now to have the greatest chance of being admitted.
 
 

Recent happenings at Space Place

by Jim Lattis

Space Place had an eventful December. Lots of interest in the Christmas solar eclipse produced many visitors to our eclipse programs on the 21st and 23rd and a good bit of positive television coverage. We also sold about 170 pairs of eclipse-viewing glasses locally and by mail order from around the state. Then on New Year's Eve our Firstar Eve programs drew about 340 visitors to Space Place for the Fun with Chemistry program, a talk on planetary exploration by Dr. Sanjay Limaye, and lots of hands-on science activities (including decorating star cookies) for kids. The skies were reasonably clear, so we were very busy giving many visitors their first looks at Jupiter and Saturn through telescopes. (see picture below) Firstar Eve, like our Telescope Fairs and Clinics (see calendar), are fertile ground for MAS recruitment, so we would welcome MAS participation at the next Firstar Eve.

2001: A look back - and forward

by John Rummel

I recently found myself in the awkward position of having no good books to read (an odd feeling for me, an library addict), and had to dig into my library and dust off an old classic, but one that seemed due for a "timely" reread: Arthur Clarke's 2001 a Space Odyssey. Having read this work several times before, there were few surprises, but I did find deep satisfaction in reading the following passage:

Like a ball on a cosmic pool table, Discovery had bounced off the moving gravitational field of Jupiter, and had gained momentum from the impact. Without using any fuel, she had increased her speed by several thousand miles an hour.

Yet there was no violation of the laws of mechanics; Nature always balances her books, and Jupiter had lost exactly as much momentum as Discovery had gained. The planet had been slowed down - but as its mass was a sextillion times greater than the ship's, the change in its orbit was far to small to be detectable. The time had not yet come when Man could leave his mark upon the Solar System.

What struck me was the fact that NASA's Cassini spacecraft has just executed this exact maneuver, using Jupiter's gravitational field to propel it on to Saturn. But contrary to the book's perspective, this maneuver is not now considered a novelty. It's been used successfully many times now - by the Pioneer, Voyager and Galileo spacecraft, and even by Cassini prior to reaching Jupiter. Cassini's unusual flight plan involved two flybys of Venus and one of Earth - all designed to use the gravity of these planets to sling it on to higher speeds as it looped through the inner solar system for two years while gaining enough speed to reach the gas giants. (read more about Cassini's flight path to Saturn here.

Arthur Clarke is regarded by many science fiction aficionados as the dean of scientific fiction. With other science trained authors such as Isaac Asimov, he is credited with putting the science back in science fiction. Clarke was remarkably on target with many of his predictions of science advancements in the 20th century. The following is from one of his early papers:

" ... An 'artificial satellite' at the correct distance from the earth would ... remain stationary above the same spot and would be within optical range of nearly half the earth's surface. Three repeater stations, 120 degrees apart in the correct orbit, could give television and microwave coverage to the entire planet."
Clarke was describing a geostationary communications satellite, something so patently commonplace today we barely give it any thought. But Clarke penned that paragraph in 1945, over 12 years before the first successful launch of an artificial satellite (basically a ball of metal with a radio beacon) into low earth orbit.

While remarkably accurate in some predictions, Clarke, like any writer willing to take a chance on predicting the future, made many inaccurate guesses. We still have no moon bases, nor any planned manned excursions to the outer planets. While we do have a space station, it doesn't have artificial gravity and a population of hundreds. And computers have come a long way, but instead of the villainous HAL, we have desktop machines capable of 1 billion calculations per second.

While science fiction writers, politicians, and psychics attempt to predict the future, we have the privilege of living it. I recall as a child thinking of the magical year 2001, so immortalized in fiction. I tried to imagine what life would be like in that distant future, when I would be nearly 40 years old. Things didn't turn out like many of the predictions, but we've survived and arrived. Now we can imagine the next step as life in the 21st century unfolds before us.

***

How does a gravity assist work?

Imagine a ball rolling down a hill. It gains speed rolling downhill, but then loses speed as it rolls up the next upslope. It's hard to see how speed can be permanently gained this way. But now imagine that the hill is being propelled forward as you roll down it. Now you're not only gaining speed due to the slope, but due to the motion of the hill as well. As you reach the bottom, you have gained more speed than you would from the gravity alone. With a moving hill and proper timing, one could utilize a "slingshot" effect to gain speed as a result. This is exactly the idea, only instead of a hill, you are approaching the moving gravitational field of a planet from behind. The spacecraft "falls" in the planet's gravitation field, and then goes "up" the other side, gaining speed in the process by "stealing" a tiny bit of the planet's momentum.
 
 

Light pollution action notes

by Karolyn Beebe

On January 16 members of Good Neighbor Lighting gathered at the Planetarium. Their efforts to fight light pollution were refreshed after being under the planetarium's dark starry sky. Thank you John Rummel and Madison Public Schools for inviting us!

Wasteful lighting subsides as awareness grows. Close to 50 people attended the January 17 Sierra Club meeting where light pollution was the topic. David Liebl presented slides and discussion of the issues involved. His last slide was of Kelly Taylor, a plant operator who saved Premcor Refinery over $172,000 a year in energy costs. By shielding the refinery lights, he achieved recommended light levels using much fewer watts, improved visibility by reducing glare, and brought more stars back over Port Arthur Texas.

That's Good Neighbor Lighting's goal for Madison. If you wish to help get us there, contact Karolyn Beebe, 246-0222 or by email.
 
 

From the Editor's Desk...

An unusually harsh December has curtailed observing for many of us. We were rewarded with a beautiful day on December 25th which made the partial eclipse a Christmas-day hit in many locations. I set up my telescope in our driveway, and also had on hand a pair of eclipse glasses, a 7x35 binocular with eclipse glasses taped over the apertures, and a pin hole projector. Even though temperatures were below zero, many neighbors came out or stopped by to take a look. A wonderful interlude in a stretch of miserable weather.

···

I've decided that as of the summer issue (June/July), I will retire as the editor of the Capitol Skies. That issue will complete my second full year at the reins and that makes it feel like a good time to hand over the controls of this newsletter to someone new. Interested parties can contact me or president Doc Greiner. I encourage anyone with the interest and the time to consider taking up this challenge.

-JR
 
 

3 Book Reviews: Biographies of Astronomers

by Dick Greiner

Over the past 6 years, I have accumulated in my personal library about 160 books on various aspects of astronomy. I have read, or at least thoroughly reviewed all of them.

I have selected brief reviews of just a few. For those interested in more reviews you can find them on my astronomy web site at www.mailbag.com/users/ragreiner.

Here are three of the best of the many I have about the lives of great astronomers. Whatever your interests, these are wonderful, even essential books about astronomical history.

Edwin Hubble, Gale E. Christianson Farrer, Straus and Giroux, New York 1995. This is a complete and through biography of a great astronomer from the beginning of his life through his significant accomplishments in changing our understanding of the universe. While he may not have been the greatest astronomer ever, he is certainly on the tip of our minds these days because of the Hubble Space Telescope. This book is the story about a lifetime quest for the truth about the structures that abound in space. The size of the universe is a critical bit of information in our understanding of the cosmos. No person was more instrumental in establishing facts about this matter. At the same time this is a gripping story about Hubble and the men about him who got astronomy on the right track toward our modern understanding of the universe. This is a great book about a great astronomer. I can recommend it highly.

Explorer of the Universe, A Biography of George Ellery Hale, Helen Wright, American Institute of Physics Press, 1994. This is a biography of one of the most influential telescope builders of the last century. Hale was a complex person, a scientist, a schemer and the driving force behind what are still three of the greatest telescopes ever built. These are the 40" Clark refractor at Yerkes, the 100" Hooker reflector and the 200" Palomar reflector. All of these instruments were the largest in the world when they were completed. They were created largely through Hale's sheer willpower and his ability to raise large amounts of money for their creation. This is indeed a wonderful biography filled with personal pathos as well as a history of how these seminal instruments came to be. It is a must read for anyone with an interest in the history of astronomy and the telescopes that made most important astronomical discoveries of the 20th century possible. Very highly recommended.

The Lord of Uraniborg - A Biography of Tycho Brahe, Victor E. Thoren, Cambridge 1990. This is a big book and a big tough read about one of the founders of scientific method as applied to astronomical observation. It goes into great detail about everything. Brahe had an unbelievably complex life in terms of his position among his relatives, kings and lords and his need to have funds for his work, which was a major expense in an era of distrust of science in general and astronomy in particular. This is all laid out in excruciating detail. There is also very great detail about his astronomical measurements, their influence on those around him and various attempts to force accurate observations into a heliocentric model which simply did not work. He of course was a direct influence on Keppler who in the early 17 century did cast some light onto the true structure of the universe. I found the book alternately exciting and boring, never easy to read but in the end an enlightening look into the struggles, successes and failures of the first great observational astronomer.


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