by Patrick L. Barry

Who in their right mind would design this bizarre- looking antenna? Actually, nobody did. It evolved. Taking a cue from nature, NASA engineers used a kind of "artificial evolution" to find this design. The result may look odd, but it works very well.

"The evolutionary process improves the design of antennas, just as evolution in nature leads to fitter plants and animals," says Jason Lohn, leader of the Evolvable Systems Group at NASA's Ames Research Center. The improvement comes from Darwin's idea of natural selection: only the fittest members of a generation survive to produce offspring. Over many generations, traits that hinder survival are weeded out, while beneficial traits become more common. "In the end," he says, "you have the design equivalent of a shark, honed over countless generations to be well adapted to its environment and tasks."

Evolutionary computation, as it's called, applies this principle to hardware design. It's particularly useful for tackling problems that are difficult to solve by hand--like the design of new antennas.

Designing a new antenna for NASA's Space Technology 5 (ST-5) mission was the challenge facing Lohn's group. ST-5 will explore how TV-sized "nano-satellites" can perform the tasks of much larger, conventional satellites at a cheaper cost. Antennas on these satellites must be smaller than usual, yet capable of doing everything that a bigger antenna can do.

The evolution of this bizarre-looking antenna happened inside a computer. Many random designs were tested in a computer simulation. The computer judged their performance against certain goals for the design: efficiency, a narrow or wide broadcast angle, frequency range, and so on.

As in nature, only the best performers were kept, and these served as parents of a new generation. To make the new generation, the traits of the best designs were randomly mixed by the computer to produce fresh, new designs—just as a father and mother's genes are mixed to make unique children. This new generation was again tested in the computer simulation, and the best designs became the parents of yet another generation. This process was repeated thousands, millions of times, until it settled onto an optimal, shark-like design that wouldn't improve any further. With today's fast computers, millions of generations can be simulated in only a day or so. The result: an excellent antenna with an odd shape no human would, or could, design.

For more about artificial evolution, see ic.arc.nasa.gov/story.php?sid=86&sec.  For more about Space Technology 5, see nmp.nasa.gov/st5. For an animation that helps explain to kids how ST5’s antenna sends pictures through space, go to spaceplace.nasa.gov/en/kids/st5xband/st5xband.shtml.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration

NEW NIGHT SKY NETWORK TELECONFERENCE
EXPLORING COMETS: THE SCIENCE OF DEEP IMPACT

Shortly after NASA’s scheduled launch of the Deep Impact mission, Night Sky Network members will have the opportunity to participate in a teleconference on the evening of January 18th (9 pm EST) with Dr. Lucy McFadden, mission Co-investigator and planetary scientist at the University of Maryland. Dr. McFadden is an expert in reflectance spectroscopy and surface composition of solar system bodies, who is also leading public education and outreach activities for the mission. She will talk about both the science of the mission and how amateurs can participate.

For those unfamiliar with the mission, Deep Impact is aptly named. The spacecraft is scheduled to arrive at comet Tempel 1 (9P) on the evening of July 4th (a day before the comet’s perihelion - typically the period in its orbit where comets are most active). That evening, Deep Impact will deploy a 1-meter 372-kilogram copper-fortified probe to impact the 14 x 4 x 4 km nucleus of the comet at approximately 37,000 kph (23,000 mph). The resulting spray of material from the comet’s subsurface will be analyzed to provide scientific insight into the composition and structure of the comet and by extension that of the early solar system.

Presently a magnitude 16 object, Tempel 1 (9P) will steadily brighten over the next 6 months. By the impact date, the comet will reach magnitude 9.7 making it readily observable with amateur equipment. Like the impact of comet Shoemaker-Levy 9 with Jupiter, NASA's space-based telescopes along with those of numerous professional and amateur astronomers on Earth will be trained on the comet. The time of impact is within a 45 minute window between 05:49 and 06:30 UT making it a potentially viewable event in the Western U.S. where the comet will be 10 to 30 degrees above the horizon at impact time.

Even if the event isn’t viewable at your location, amateurs have a role to play in monitoring the comet for activity and changes in brightness in the months prior to and immediately following the impact. In addition to sharing information about the mission, Dr. McFadden will explain how the amateur astronomy community can contribute to the science of this mission through the Small Telescope Science Program and other public outreach programs. (http://deepimpact.umd.edu/stsp/).

As I don’t have the details yet, please contact me at blgeigle@comcast.com,  for further information. The details are supposed to be set up at least several days before the teleconference.

REMINDERS:

- NOVA presents "Welcome to Mars," Tuesday, January 4, 2005 at 8 PM ET (check local listings) on PBS (www.pbs.org/nova/ mars). The program presents the findings of the two rovers in their nearly year-long investigation of the red planet.

- Deep Impact Mission to Launch from Kennedy Space Center, January 12. Educators are invited to attend the Deep Impact Winter Science Academy at Kennedy Space Visitor Center on January 11, one day prior to the launch of the Deep Impact spacecraft at Cape Canaveral. NSN members are welcome to attend as informal educators or share this opportunity with a teacher. Details can be found at: http://deepimpact.umd.edu/workshop/index.html

- Huygens Rendezvous with Titan, January 14. This mission was featured in our July teleconference when Dr. Stephen Gillam of the Jet Propulsion Lab provided the Night Sky Network with an evening telecon reviewing the Cassini mission and specifically what scientists are hoping the Huygens probe will reveal about Saturn's moon Titan. You can download Dr. Gillam’s PowerPoint presentation by going to Tool Kit Downloads and clicking on "Teleconference" or go to http://nightsky.jpl.nasa.gov/docs/GillamCassini2.ppt.

- If anyone is planning a program in February or March, and would like free copies of the magazine "Night Sky" to hand out, please contact me by January 4 so I can order them.

Clear skies,

Barb Geigle

Treasurer’s Corner

By Linda Sensenig who Makes Sense of Our Dollars

DUES ARE DUE.

If there is a brightly colored notice attached to your Pegasus, it means you owe dues for the year 2005. If you joined sometime during the year 2004, your dues have been pro-rated to bring you to the end of 2005. As in the past, unless you joined during the year, if your dues are not paid by the end of January there is a $2.50 late fee added. If you received a brightly colored notice and feel you already did pay dues for 2005, do not ignore the notice. Contact me so I can resolve the discrepancy.

HELP WANTED: Need somebody who is interested in sharing his or her knowledge of the night sky with other club members, but would like to do it without having to go outside in the cold weather. You only need to know what is in the night sky and how best to observe it. One of the things that Pegasus has traditionally lacked that other club newsletters have is information on what to observe and how to observe it. There are a lot of beginners who could go outside and observe if they knew what to look for. Some months the article could be naked eye, sometimes telescope. This would be something that would appear in each issue (but the world would not come to an end if you missed an issue). If you are interested, please contact Melody Gardner - or just start sending her articles for Pegasus.

Do you own every astronomy gismo and gadget on the market and still can only find the planet Jupiter with your onboard GoTo technology? When asked at a club gathering where M33 is in the sky and your reply is "let me punch it up on the computer so we can track to it." Or, do you have to open your Farmers’ Almanac to answer what phase is the moon in tonight. If you answered Yes to any of these situations, you may need to think about becoming a real Astronomer.

So you ask, "How do I aspire to become a real Astronomer?" All of this verbal slamming is leading up to an introduction to the Astronomical League’s Observing Clubs. If you are unaware, as Berks Astronomy Club members, we are all members of the Astronomical League and can obtain a certificate and pin in any of their observing clubs. There are a number of observing clubs available to you to help you aspire to be a better astronomer. There a clubs that let beginners take a crack at learning the basic constellations of both the northern and southern skies. There are clubs for the advanced Amateur Astronomer as well. There is an urban club for those light pollution impaired budding Astronomers as well as a Lunar Club for those of you in cities or country settings. For those of you who do not own a light bucket, there are a number a clubs that only require you to use your naked eyes and or a pair of binoculars.

Here is a list of the 22 current observing clubs offered by the Astronomical League and if you receive the Astro Leagues newsletter, The Reflector, they are all listed in there as well.

To see how to start the process of earning any of these certificates and pins, you can visit the Astronomical Leagues’ web site, http://www.astroleague.org/al/obsclubs/obsclub.html or contact any of our clubs’ officers for information on getting started.

There have been a few of current and past club members that have achieved their certificates and have become more educated Astronomers. There are also members who may have started the tasks assigned in the observing clubs and are in the process of working towards their certificates, me included. I have listed some of the Berks Astronomy Club members who have earned their certificates below. The most popular observing club appears to be the Messier Club in which there are over 2000 awardees to date. Try to get your name on the list and become one of our REAL Astronomers.

Binocular Messier Certificate
Priscilla Andrews – 1992-Oct-16

Lunar Club Certificate
Elise Donaghy - 1998-Sep-28

Messier Club Certificate
Frank R. Pentz - 1974-Sep-28
Robert Kummerer - 1976-Jan-01
Bob Capone - 1996-Mar-11

As you can see, there are not very many Berks Astronomical Club members on the lists of Astro League Certificate Awardees. I’m sure their lists of awardees will be around for many years to come. So try a program or two and get your name on the roster for the whole world to see and in the process, improve your knowledge of the heavens.

Michael F. Bashore (stararbash@enter.net)
Not yet a real astronomer

Lunar Eclipse
by Bob Frantz

I went to the lunar eclipse watch and spent a pleasant evening with friends watching the shadow of the earth making its way across the moon. The night was slightly spoiled by some cloud cover, but it was calm and warm. As I watched the progress of the eclipse a funny thought came to me. I wonder how the Flat Earth Society people would explain the curved shadow as the moon slid behind the edge of the earth. They are the ones who seriously believe that the earth is flat and that all of the space shots and moon explorations were faked using Hollywood special effects.

In fourth grade history class we were told that in the days of Columbus, everyone believed that the world was flat, and that if you sailed too far from land you would fall off the edge. That seemed a bit far fetched even for me at age ten because there would be no reason to try to find a sea route to China and India if that were true. I guess they wanted to keep things simple for fourth graders. As we know, educated people knew that the earth was round for over a thousand years before Columbus' voyage. It probably is true that illiterate peasants thought that the world was flat. Most people of that time could not read or write and never traveled more than thirty miles from their place of birth. Communication was so poor that one part of the world could have knowledge that the rest of the world might not get for hundreds of years. It was normal for there to be no technological change at all in most peoples lives. It sounds pretty boring to a techie like me.

Columbus was a master seaman and navigator. He had a great reputation and was able to sell his plan to Queen Isabelle and her court. There were two things wrong with his plan. First, there was little knowledge about the land masses of the earth and most geographers guessed that the earth was more than half covered by land. As we know, it is less than one-third. Secondly, Columbus used a number for the diameter of the earth that was only three fourths the real diameter. This is such a glaring error that historians speculate that he deliberately used the smaller number to help sell his plan. During his voyage he used celestial navigation to keep track of his latitude, but in those days before reliable clocks, he could only guess at longitude by dead reckoning. The net result of Columbus' errors was that the trip across the ocean was longer than he expected and he guessed that he had reached India. The fact that many more trips were made shortly after his first one tells us that sailing technology was ready for European exploitation of the New World.

In the era of ultra political correctness in the nineteen eighties, historians rewrote history to vilify Columbus for bringing European diseases to the New World, and for the plundering and enslaving of Native Americans. Columbus was just a sailor, a man of his times. I hear that historians have stopped vilifying him as that is now out of style. History sure does change a lot.