Pegasus
Volume XXX Issue 4
July / August 2004
In this issue:
Pegasus is a bimonthly publication of the Berks County Amateur Astronomical Society
Editor/Desktop publisher: Melody Gardner
E-Mail submissions may be made to: dblhlx@earthlink.net
Based on the BCAAS event schedule I’d say summer is here. The deluge of scheduled events that came with spring have occurred and now we go into the doldrums of summer’s heat and humidity, and a reduced schedule load. I’m not aware of single private star party scheduled for all of July and August, and only one public event, that being the annual event at Hawk Mountain on August 21st. What a change since spring!!
July does however boast two major star parties. July 8th to the 11th is the first annual star party at Green Bank, West Virginia. This star party is on the grounds of the famous radio telescopes and tours are available. Skies here are very dark as I experienced first hand back March of this year. And if you don’t care to travel the six plus hours to Green Bank, then on July 16th to the 18th is the Astronomical Society of Harrisburg’s S4 Star Party. S4 is short for Susquehanna Summer Star Spectacular. It will be held at Pine Grove Furnace State Park near Newville, PA, just west of Carlisle. If interested their web site is http://www.s4starparty.org/
Of recent events, I would be remiss if I didn’t mention the Transit of Venus on June 8th. About 10 BCAAS members braved the heavy dawn fog and mist and were well rewarded by a fantastic view of Venus’s black shadow on the disk of the Sun. We watched the last two hours of this spellbinding six-hour crossing and by 7:30 AM it was all over. For more details about the club’s Venus Transit watch, please see the article later in this issue.
As a reminder to the BCAAS membership, there are at least seven club telescopes available for use. There are two highly portable 4½" Bushnell "ball" telescopes. One has a tripod mount, but you can use any reasonable camera tripod as a mount for the other telescope. Both of these also have solar filters. There’s a 10" Cave Newtonian on a Dobson mount. This scope is definitely portable for a healthy adult. In addition the club also has an 8" LX200 Schmidt-Cassegrain and two not so portable 8" Cave Cassegrains on heavy equatorial mounts. These latter two require some sort of semi -permanent site as they are very heavy and huge, but the mounts are on rollers so they could be rolled out of a garage and set up on the driveway for viewing. The 8" LX200 is portable by an adult. And lastly there is the 4" Unitron refractor. This is our club’s only refractor, another fine scope, a bit bulky but portable. Many of these telescopes currently reside at my home, or nearby, and they are all lonely and need some use, so please call me for details if you would like to borrow any of them.
The last thing I wanted to alert the membership to was coming changes in BCAAS’s meeting arrangements. Starting September 1st the museum is moving our meeting room to the Planetarium. Since our August meeting is the annual picnic at Dave Brown’s farm, our July meeting will be the last meeting in the Museum’s auditorium. The BCAAS Board is currently looking into other alternatives besides the option of moving to the Planetarium, so changes of one sort or the other are definitely coming. If you have any suggestions, please call me.
Ron Kunkel, at rikunk@comcast.net or 610-488-6039, and Clear and Dark Skies to All.
Niccolo Zucchi was a Jesuit and scientist, a thinker to make one proud of the Jesuits and impatient with them at the same time. Following hidebound scholastic natural philosophy (which was hopelessly wedded to the theories of pagan Greece) he rejected the possibility of vacuum, despite barometric evidence indicating otherwise. He argued that Venus was closer to the sun than Mercury because Venus represents beauty and Mercury skill. On the other hand, he invented the first concave reflecting telescope (which he could never get to work right). Most importantly, on May 17, 1630, he became the first to discover two of the belts of Jupiter. He met Kepler (who tried one of his telescopes), was a preacher to the pope, and late in life headed a Jesuit house in Rome. (from the on-line newsletter of the Christian History Institute)
by Ron Kunkel
This past June 8 various BCAAS members witnessed the 2004 Transit of Venus, aka ToV. A transit of Venus across the face of the Sun, unlike a transit of Mercury is very rare. Venus transits occur in pairs that are eight years apart, but then there are either 105 or 122 years between pairs. The last transit occurred in 1882, so no living individual on Earth had ever observed such an event. Nine BCAAS members observed and witnessed the June 8, 2004 transit from our Flying Field observing site between Centerport and Bernville.
The historical significance of a transit of Venus is that the transits of the 1700’s and late 1800’s enabled astronomers to finally establish the length of the astronomical unit, AU. For many years, based on maximum elongation measurements of the planets from the Sun, the relative distances of the planets from the Sun were well known. By definition 1 AU was the average distance from the Sun to the Earth, and 0.72 AU was Venus’s distance from the Sun. The problem was no one knew how long an AU was in absolute miles. The transits of Venus enabled astronomers to finally establish this length and thus establish the size of our Solar System.
The methodology of measuring the length of the AU is fairly involved. By observing the transit of Venus from two widely separated locations on Earth, the parallax of the two observations enabled one to calculate how far apart the two apparent paths of Venus were in absolute miles. This enabled astronomers to measure the size of the Sun in absolute miles. Then based on the apparent size of the Sun and it’s actual size, the length of the AU could be calculated.
The actual path of Venus across the Sun was determined most accurately by timing the various contacts points of the planet with the Sun. First or I Contact was when the planet just started to occult the Sun. II Contact occurred when the planet’s shadow was fully inside the edge of the Sun. Similarly, III and IV contacts were when the planet exited from the face of the Sun.
An entire transit of Venus across the face of the Sun lasts about six hours. Unfortunately for observers in North America, most of the transit already occurred while the Sun was still below our horizon as thus out of our view. But once the Sun rose at 5:34 AM EDT we could observe the last two hours of the transit, including the III and IV contacts.
On the morning of June 8th, the earliest arrival at the observing site, your truly, came about 3:00. I wanted to be sure the equipment was set up and ready to go by the time the Sun rose. Most of this time was actually dedicated toward making sure the optics were in thermal equilibrium to ensure the best possible imaging. By 5:30 AM about nine other members had arrived. This included Barb Geigle, Mike Bashore, and myself who had telescopes set up. Other observers were Sam Tyson, Gene and Hanna Salvatore, Kathy Manzella, Tim Siminski, and Paul Haggard. Bret Cadmus had arrived but quickly left for home again as his home site had considerably less ground fog and he was concerned that we might not see anything. So were we!!!!
The weather on the morning of June 8th was a warm 60 degrees, calm, and clear. However there was an extensive ground moisture in the form of a heavy mist or fog very close to the ground. The zenith was quite clear so we knew that once the Sun rose above the low lying fog we were going to see something, the only question was just how much were we going to see of the transit before it ended at 7:26.
The theoretical Sunrise was at 5:34 AM, but no Sun was visible even from the relatively high elevation and clear horizon view of the Flying Field. This was due primarily to the heavy ground fog. But by 5:45 we could see the faint outline of the Sun’s disk as a very reddened ball through the fog. We were actually observing the Sun naked eye through the dense fog, and we could clearly see that the Sun had a very dark blemish on it’s surface, the shadow of Venus. I was personally was impressed by Venus’s shadow. It appeared very black and unexpectedly large. It was readily visible naked eye. We observed the Sun this way for about 15 minutes, but then it began to brighten dramatically as it rose above the dense ground fog. We quickly installed our solar filters onto our telescopes and continued observing.
Mike Bashore took some film shots of the transit, and I managed to capture the last 42 minutes of the transit, through III and IV Contact, onto video. In 42 minutes I captured about 77,000 individual frames of the transit into a 261 MB file. I’ve process this video into a short animated gif file, only 1.2 MB in size, and shortly expect to also make up a mosaic of images. If anyone is interest in either of these, please contact me and I’ll email you the processed images.
The observation of the transit was truly a once, or possibly twice in a lifetime event. I do hope to observe the 2012 transit, but that event will again only be partially visible from North American, this time at Sunset. I don’t expect to be around in 2117 for the next Transit of Venus.
NASA Spacecraft Reveals Surprising Anatomy of a Comet
June 17, 2004
Findings from a historic encounter between NASA's Stardust spacecraft and a comet have revealed a much stranger world than previously believed. The comet's rigid surface, dotted with towering pinnacles, plunging craters, steep cliffs, and dozens of jets spewing violently, has surprised scientists.
"We thought Comet Wild 2 would be like a dirty, black, fluffy snowball," said Stardust Principal Investigator Dr. Donald Brownlee of the University of Washington, Seattle. "Instead, it was mind-boggling to see the diverse landscape in the first pictures from Stardust, including spires, pits and craters, which must be supported by a cohesive surface. Stardust gathered the images on Jan. 2, 2004, when it flew 236 kilometers (about 147 miles) from Wild 2. The flyby yielded the most detailed, high-resolution comet images ever.
"We know Wild 2 has features sculpted by many processes. It may turn out to be typical of other comets, but it is unlike any other type of solar system body," Brownlee said. He is lead author of one of four Stardust papers appearing in the Fri., June 18, issue of Science. "We're fortunate that nature gave us such a rich object to study." Stardust images show pinnacles 100 meters tall (328 feet), and craters more than 150 meters deep (492 feet). Some craters have a round central pit surrounded by ragged, ejected material, while others have a flat floor and straight sides. The diameter of one large crater, called Left Foot, is one fifth of the surface of the comet. Left Foot is one kilometer (.62 miles) across, while the entire comet is only five kilometers (3.1 miles) across.
"Another big surprise was the abundance and behavior of jets of particles shooting up from the comet's surface. We expected a couple of jets, but saw more than two dozen in the brief flyby," said Dr. Benton Clark, chief scientist of space exploration systems, Lockheed Martin Space Systems, Denver.
The team predicted the jets would shoot up for a short distance, and then be dispersed into a halo around Wild 2. Instead, some super-speedy jets remained intact, like blasts of water from a powerful garden hose. This phenomenon created quite a wild ride for Stardust during the encounter.
"Stardust was absolutely pummeled. It flew through three huge jets that bombarded the spacecraft with about a million particles per second," said Thomas Duxbury, Stardust project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. Twelve particles, some larger than a bullet, penetrated the top layer of the spacecraft's protective shield. The violent jets may form when the Sun shines on icy areas near or just below the comet's surface. The solid ice becomes a gas without going through a liquid phase. Escaping into the vacuum of space, the jets blast out at hundreds of kilometers per hour.
The Stardust team theorizes sublimation and object hits may have created the comet's distinct features. Some features may have formed billions of years ago, when life began on Earth, Brownlee said. Particles collected by Stardust during the Wild 2 encounter may help unscramble the secrets of how the solar system formed.
Stardust was launched in 1999. It is zooming back to Earth with thousands of captured particles tucked inside a capsule. The capsule will make a soft landing in the Utah desert in January 2006. The samples will be analyzed at the planetary material curatorial facility at NASA's Johnson Space Center, Houston. Comets have been objects of fascination through the ages. Many scientists believe they delivered carbon and water, life's building blocks, to Earth. Yet their destructive potential is illustrated by the widely held theory that a comet or asteroid wiped out the dinosaurs.
Stardust, part of NASA's Discovery Program of low-cost, highly focused science missions, was built by Lockheed Martin Space Systems and is managed by JPL for NASA. JPL is a division of the California Institute of Technology in Pasadena.
To view Stardust images on the Internet, visit: http://stardust.jpl.nasa.gov or http://photojournal.jpl.nasa.gov/ .
Private craft soars into space, history
By Michael Coren, CNN
Wednesday, June 23, 2004 Posted: 1:02 PM EDT (1702 GMT)
MOJAVE, California (CNN) -- The man who became the first person to pilot a privately built craft into space called his flight "almost a religious experience" after his safe landing Monday morning. Test pilot Mike Melvill landed at Mojave Airport, about 80 miles north of Los Angeles, California, after taking the rocket plane SpaceShipOne to an altitude of more than 100 kilometers (62.5 miles) -- the internationally recognized boundary of space.
Melvill told reporters he had "a hell of a view from 62 miles." "The colors were pretty staggering from up there," he said. "Looking from the Earth up there, you know, it's almost a religious experience. It's an awesome thing to see. You can see the curvature of the Earth. I could see all the way out, way out past the islands off the coast of Los Angeles."
SpaceShipOne lifted off early Monday morning in the Mojave Desert, carried by the jet White Knight. As the pair approached 50,000 feet, SpaceShipOne decoupled from the jet. After a brief glide, Melvill ignited the spacecraft's engines and ascended into space at Mach 3, three times the speed of sound. Melvill said once he reached weightlessness, he opened a bag of M&M's in the cockpit, and the candies floated for three minutes while the ship soared high above California.
Problems cut flight short
The spacecraft returned safely, but control problems revealed after the flight forced Melville to cut it short and use a backup system to keep SpaceShipOne under control. He said trim surfaces on SpaceShipOne -- movable surfaces on the craft's wings -- jammed during supersonic flight. The craft rolled 90 degrees twice during its vertical ascent and veered more than 20 miles off course in a few seconds. "Right at top, I tried to trim the nose up, that's when I had the anomaly and had to switch to backup," he said. The craft peaked at 328,491 feet (100.12 kilometers), just 408 feet (124 meters) above the international boundary of space, according to Scaled Composites.
The trim surfaces were reconfigured for landing and then remained unused as Melvill guided SpaceShipOne back to a comfortable landing." It was a pretty smooth ride after that," he said. "I headed back to Mojave as fast as I could without reasonably hurting anything."
A loud bang Melvill heard during the flight appeared to be a nonessential part of the composite airframe buckling near the rocket nozzle. The slight indention in SpaceShipOne's exterior did not affect the craft's performance.
Melvill, 63, picked up the nation's first pair of commercial astronaut's wings from the Federal Aviation Administration. "We have opened the frontier of human space flight," said Pattie Grace Smith of the FAA. "It's a major step ushering in a new era of low-cost space flight ... in reach of ordinary citizens. "The flight marks the pinnacle so far of Burt Rutan's vision of affordable, safe, private space travel. Rutan's company, Scaled Composites, built SpaceShipOne with financial backing from Paul Allen, co-founder of Microsoft Corp., for a little more than $20 million. Rutan said the flight, which went from a concept in 1995 to reality less than a decade later, was the realization of a long dream. "I'm so proud of that, it brings tears to my eyes," he said.
The rocket plane made its farthest and fastest flight to date. Rutan said he would not speculate about the problems until technical data had been reviewed, something he expected in the next few days. "The anomaly we had today was the most serious safety system problem we've had in the entire program," he said. "The fact that our backup system worked and we made a beautiful landing ... makes me feel very good." Melvill, who has tested Rutan's planes extensively, reaffirmed Rutan's engineering skills and commitment to safety. "That's why we are so good at what we do," Melvill said. "We cover all the bases."
A prelude to future flights
Those on hand for the launch included officials from NASA, the FAA, the X Prize Foundation and the Guinness Book of Records.
Peter Diamandis, co-founder of the X Prize, the $10 million award intended to spur civilian spaceflight, said Rutan's vision would open the door for those with the same dream.
"This is a warm-up for the Ansari X Prize, but it's a historic moment for all Americans," he said. "[I've heard], 'If God wanted us to fly into space, he would have given us more money'. Hopefully, the technology demonstrated here today will lead to designs that are cheaper and easier."
Scaled Composites is one of 24 companies from several countries competing for the X Prize, which will go to the first privately funded group to send three people on a suborbital flight 62.5 miles high and repeat the feat within two weeks using the same vehicle. Rutan said SpaceShipOne would compete for the X Prize once the causes be hind the anomalies had been resolved.
"We will be looking at all our data," he said. "We'll make a decision next few days." After that, preparations for an official X Prize flight are finalized will take 60 days. "This was not a perfect flight," Rutan said. "Then again a lot of these things you can do with a 60-day window and easily fix them."
The nonprofit X Prize Foundation is sponsoring the contest to promote the development of a low-cost, efficient craft for space tourism in the same way prize competitions stimulate d commercial aviation in the early 20th century.
The prize is fully funded through January 1, 2005, according to the foundation's Web site. The remote Mojave Airport, a licensed spaceport and the world's only civilian test flight center, also played host to an assortment of vehicles that converged on the site from around the country.
Spectators witness history
Buses, RVs, electric scooters, small ultra-lights and a variety of other vehicles were parked in the sandy soil across from the runway. Many of the spectators said there was a feeling of history in the air. Some said that after waiting decades, they were finally witnessing the first steps toward spaceflight for them.
Josh Collins, 25, said he had flown from Maryland to see the attempt. "Some people thought I was crazy, other people are jealous," he said.
Rutan mingled, talked and directed traffic with those who spent the night on the windy Mojave Desert floor across from the airstrip Sunday night. He saved one sign as a memento of the occasion:
"SpaceShipOne; GovernmentZero".
The Beginner's Corner
Recording Our Experienceby Eric Knight
Astronomy is a hobby that provides rich new experiences for every amateur astronomer, but experienced amateur astronomers say that one of the biggest and most common mistakes made by beginning amateur astronomers is not recording what they see and learn. Their recommendation is to keep a log of observations and notes.
If we rely on memory alone, we will only be able to recall a fraction of what we see and hear. When we observe an object in the sky, we want to be able to find our way back to it. When we hear or read about something new in the field of astronomy, we want to be able to recall what we have learned. Both become easy with the aid of a log.
There are many recommendations on how to keep a log of your astronomy experiences. I have even seen log books, organized with appropriate items to record, for sale in the astronomy magazines. Your log can be as simple as a small spiral notebook, or as elegant as a computer program. You can even keep it on your PDA.
Long time club members have varied methods of recording their observations and notes. Larry Citro keeps some of his data in the headers of his CCD images, and other notes and data in a journal or diary format. Our president, Ron Kunkel keeps the articles he wants to read and learn about in his log notebooks.
I organize my log in two sections: observations and notes. I keep it in a notebook so I can drag it around with me. My notes section is journal or diary format with a date and whatever information I feel I need for future reference. My observations section is fairly structured so that I can not only find my way back to what I observed, but also satisfy my need to learn as much as I can about what I am observing. I created my observations log form using a Microsoft Word table so that I can alphabetically sort on the object name when I type the information onto my PC. The items (or table columns) are:
· Object name
· Description and story
· Date, place and conditions of observation
· Location (directions – how to find the object)By now I have the most important items memorized so I can record an observation on a scrap of paper, a napkin or the little spiral notepad I carry around, and copy it back into my observations notebook later.
Recently, I added a URL section for astronomy web sites I like and want to get back to. You can do that with the favorites on your web browser, but a notebook entry lets you record what you like about the site.
If you want to look at some other examples, use "astronomy log" on a web search. You will get hundreds of hits for both examples and blank template forms that you can use to record your own observations and data.
The final thing about a log is that you need to review it periodically to bring back the memories of finding objects in the nighttime sky, and to learn the information you recorded in your notes.
However you decide to do your log, the important thing is to use it and review it. That way the rich experiences we have as amateur astronomers will not be lost over time to the frailties of our memories.
Thursday, July 8th @ 7:30pm — BCAAS meeting, Peter Detterline "MARS Student Data Team"
Saturday, August 14th - BCAAS Picnic at Dave Brown’s farm
**********************************************************************
NOTE: There is NO regular meeting in August, so please don’t show up at the museum, you’ll scare the security guard!!!
**********************************************************************Saturday, August 21st @ dusk - Starparty at Hawk Mountain
It’s calendar time again. I know, it’s only July. However you might remember that last year we had intended to wait until the end of October like usual to order the calendars, however we had to hastily move that up because Kalmbach was running out of calendars! This year, we are going to order the calendars right after the September meeting (unless Lucy from Kalmbach calls back before that time and issues another alert!). The cost again this year is $6.00 and the calendar is another Deep Space wall calendar. Please give me your calendar order as soon as possible in case we need to quickly move the ordering date up like we did last year. This $6.00 is 50% off the retail price of the calendar, so the discount is significant for club members.