Battle Point Astronomical Association

(unless otherwise noted, all events are at the Edwin Ritchie Observatory, Battle Point Park)

December
December 2 - 7 p.m. Board Meeting
December 5 - First Quarter moon
December 7 - John Rudolph Memorial Planetarium Fund Kiwanis Brunch, Wing Point
December 12 - Full Moon; 7 p.m. Members Meeting, "Mars - A New View from Space Probes to Landers" Talk by Dr. David Fong, Olympic College Astronomy Professor
December 13 - Geminids Meteor Shower Peak
December 19 - Third Quarter moon;
December 20 - CANCELLED DUE TO WEATHER - 5 p.m. Planetarium Show: "Take a Ride on the Orion Nebulae, Birthplace of Stars" and Star Party
December 21 -  Winter Solstice (4:04 a.m. PST)
December 22 - Ursids Meteor Shower Peak
December 27 - New Moon

January
January 1 - International Year of Astronomy 2009
January 3 - Quadrantids Meteor Shower Peak
January 4 - First Quarter Moon; John Rudolph Memorial Planetarium Fund Kiwanis Brunch, Wing Point; Earth at Perihelion (0.983 AU from Sun)
January 9 - 6:30 PM - Appreciation dinner for Eric Cederwall & George McCullough. RSVP by Jan. 7 to hcolvin@comcast.net
January 10 - Full Moon
January 14 - 7 p.m. BPAA Annual Meeting & board election; open to all members
January 17 - Third Quarter Moon;  7 p.m. Planetarium Show: "The Winter Necklace In Our Culture and In Others" and Star Party
January 26 - New Moon;

February
February 1 - John Rudolph Memorial Planetarium Fund Kiwanis Brunch, Wing Point
February 2 - First Quarter Moon
February 4 - 7 p.m. BPAA Board Meeting
February 7 - Astronomical Society of the Pacifc’s 120th Birthday (1889)
February 9 - Full Moon; Penumbral Lunar Eclipse
February 10 - Deadline for spring issue of BPAA Quarterly
February 13 - 7 p.m. Members Meeting (subject to cancellation; check bpaa@yahoogroups.com)
February 15 - Galileo Galilei’s 445th Birthday (1564)
February 16 - Third Quarter Moon;
February 21 - 7 p.m. Planetarium Show: "The Andromeda Galaxy" and Star Party
February 21-28 - 25th Annual Winter Star Party, West Summerland Key, Florida
February 24 - New Moon

Any member who is planning to observe can invite others to join in by sending an email to bpaa@yahoogroups.com. To join our email group, send an email with your name to bpaa-owner@yahoogroups.com and we can enroll you. If you want to have web access to the messages and fles, you can join the Yahoogroups by clicking the register link for new users on http://groups.yahoo.com/:request to join at: http://groups.yahoo.com/group/bpaa/. The system will send us a message, and we’ll approve your request after we verify your membership.

Diane Colvin, BPAA Events Manager

There are more bright stars to be seen in this season than any other. If the nights are clear, of course. Hope for the best on December 1st when the three brightest objects in the night sky, Venus, Jupiter and the crescent Moon, will form a 3-degree triangle in the west at dusk. This conjunction, the best of the year, will be a beautiful sight. On December 29, the Moon occults Jupiter. At dusk on December 31, Venus will be 3 degrees from the crescent Moon.

Winter also brings us meteor showers. The Geminids are generally one of the best meteor showers of the year. They radiate from the constellation Gemini and peak at 50–80 meteors per hour on December 13. Unfortunately, the glare from the full Moon will interfere. The Ursids, radiating from the Little Dipper, peak on December 22, but with a maximum of only ten per hour. The Quadrantids are stronger, but the radiant, where the constellation Hercules, Bootes and Draco meet in the sky, is low in most of the Northern hemisphere. The peak is on January 3. On February 9, there is a penumbral lunar eclipse: the Moon passes only through the Earth’s penumbra. It is difficult to see because the Moon still looks full, just dimmer than usual. Catch it if you can, it will occur at Moonset in our part of the world.

2009 is the International Year of Astronomy. So declared by the United Nations, it celebrates the first astronomical use of the telescope by Galileo, 400 years ago. The aim of the IYA2009 is to stimulate worldwide interest, especially among young people, in astronomy and science. Sounds a lot like what we do. IYA2009 should at the least generate some useful resources for amateur astronomers and science educators. To see what’s available go to http://www.astronomy2009.org/.

It’s never too early to start thinking about star parties. For those of you who’d like to get an early start, and a break from a Pacific Northwest winter, the 25th annual Winter Star Party is scheduled for February 21–28, 2009. It is sponsored by the Southern Cross Astronomical Society and is held in the Florida Keys. This is one of the largest star parties in the country and has many devoted returnees. Before you go, check out the warnings about the fire ants at www.scas.org.

Join us for our Members Meeting on December 12. Dr. David Fong, BPAA member and astronomy professor at Olympic College, will present a talk on Mars, its geology  and weather, including scientific highlights from recent and upcoming missions.

Mars Science Laboratory, a long duration rover equipped to perform scientifc studies of Mars. Credit: NASA

On Friday, December 19, we’ll be honoring longtime members Eric Cederwall and George McCullough for their many years of service to BPAA, Eric as treasurer, and George, most recently as Vice President and procurer of interesting speakers for the monthly members meetings.

And don’t forget BPAA’s Annual Meeting January 14. This meeting is for all members and includes election of officers. Please note that the December planetarium show will start at 5:00 p.m., but the January and February shows will begin at 7:00 p.m. We’re instituting the later start times to accommodate both visitors and volunteers who find earlier times difficult

Anna Edmonds

Why is the moon so fascinating? What makes it both so romantic and so mysterious? Why is it that some of us have no trouble explaining the seasonal appearances of the constellations but we are puzzled trying to explain the appearances and disappearances of the moon?
I’ll start with some of the puzzles— the moon’s phases.  To simplify, here’s a short outline:

Dark-of-the-moon, dark moon, new moon (astronomical meaning)

We don’t see it.
Its position is directly between us and the sun (conjunction).
The sun is illuminating the side away from us and it doesn’t produce its own light.
If it’s in just the right place it will get in the way of the sun’s light causing a solar eclipse.

New moon (traditional meaning)

First visible crescent of the moon
The moon rises and sets at nearly the same time as the sun.
It will be south at noon.
First seen over the western horizon in the brief period between sunset and moonset.
It is a waxing crescent moon.
From first appearance of the new, crescent moon until full moon the moon continues to wax.
It will rise later and later during the day.
Until first quarter it is waxing crescent; the sunlight covers more and more of the side towards the earth.

First quarter

The moon rises at noon.
It is due south at sunset.
It sets at midnight.
From first quarter to full moon it is a waxing gibbous (lopsided) moon.

Full moon

The moon rises when the sun sets.
It is due south at midnight.
It sets at sunrise.
It is fully behind the earth in relation to the sun, but not always in the same plane.
If it’s in just the right place the earth will block the sun’s light and there will be a lunar eclipse.
From full moon to dark-of-the-moon the moon is waning; the sunlight covers less and less of the side we see.
Until third quarter it is a waning gibbous moon.

Third quarter

The moon rises at midnight.
It is due south at sunrise.
It sets at noon.

Maybe that outline can help with the next puzzle of where it is when we don’t see it.  It’s always there circling around us. It always rises in the east and always sets in the west. Always! When it’s new it appears first in the west; we just haven’t seen it because of the sun’s glare.

There’s a more complicated puzzle in its revolution around the earth:  It doesn’t revolve around us in the same plane that the earth revolves around the sun. That is, its plane is tipped about 5° relative to the already tipped plane of the earth’s orbit around sun (the ecliptic). The moon and the sun are opposite each other in relation to the earth twice a month (full moon and dark of the moon), but the moon isn’t always in the same plane as the sun. It may be above or below it. If it happens to be in the same plane there will be an eclipse (lunar, if it is full, solar if it is new); that could happen as many as seven times a year, but more than two are rare. Lunar eclipses are visible from the whole night-time hemisphere of the earth; solar eclipses trace a relatively short, relatively narrow path across the earth during the daytime. (Of course not all eclipses are total.)

Still another puzzle: What’s on the moon’s other side?  We see only about half of it. The moon takes 27.3 of our days to spin on its axis, and it takes the same time to orbit the earth. In other words, the moon always presents the same side to the earth. It wasn’t until 1959, when the Soviets sent a rocket to go around it, that anyone saw the back side.
And one more: Is it by chance alone that not only is the moon just the right size but also that it’s at just the right distance relative to the earth and the sun that every so often it can produce a total solar eclipse?

So—maybe the questions should be not so much why it is so puzzling, as why it is so fascinating.  I say, half in jest, that I’m a sun-worshipper in Seattle.  The sun is the much more powerful body, but it’s the full moon that makes me reach for my husband’s hand. Why? Romantic mystery? Poetic myth? Eternal and ever-recurring anticipation? Or am I caught in its phases?

by Jeanelle Miller

With the changing of the seasons comes the turning of the leaves, our signature gusty storms, colder weather, and of course, lots of rain. One thing you might not expect to find in the onset of winter is something new, but as you peruse this newsletter, the Web site, and other group paraphernalia, something new is exactly what you’ll find. Earlier this year, BPAA decided it was time to overhaul the logo.

The original BPAA logo was designed by John Rudolph. It featured a silhouette of the dome, a schematic diagram of the Ritchie telescope, and a spiral pattern. This spiral is actually a Native American petroglyph representing the journey and movement of the rising sun. We felt that the new logo should be more friendly to the public and be able to catch the attention of even those completely unfamiliar with astronomy.  In keeping with the meaning of the petroglyph—journey, progress, and new beginnings—we reached a consensus that it was time for a change.

Newsletter editor Vicki Saunders and newly acquired poster maven Jeanelle Miller created several designs for a new logo. Members discussed and voted on the drafts during a member meeting; the general public had a chance to make their choice during a planetarium show. They settled on one of Jeanelle’s designs. After some final  revision, it became the logo now featured in the Newsletter and on the amazing new brochures! It features the silhouette of the observatory with the Big Dipper asterism as a backdrop. Our hope is that this new look will be more appealing and a better representation of what our organization is all about; sharing the love of astronomy with the public.

With the new logo finished, Vicki was inspired to redesign the Newsletter to go with it. A new era for the organization is beginning and with the accomplishments we have already made, there is no doubt that we are headed for greater things

by Harry Colvin, BPAA President

Winter returns with all the rain and cloudy nights. As far as I am concerned our remote telescope system can’t be funded soon enough.

We have had a productive summer of planetarium programs and star parties and successful efforts to fund needed equipment and infrastructure improvements to the Ritchie Observatory. The Parks Foundation awarded the BPAA $4,000 for the purchase of a stable telescope mount that will allow us to accurately find and track sky objects (see page 7). The mount that we have purchased allows us to use our video camera systems to project images of objects onto a computer screen for viewing by more than one observer and by persons who are disabled and cannot view through a telescope eyepiece. In addition the mount is sufficiently stable so that we can now use a variety of telescopes for CCD imaging and for teaching CCD imaging techniques.
The funding drive to match a $50,000 challenge grant from the Seattle Foundation has begun. We will need each BPAA member to contribute time and, if possible, money to make sure we meet this match by June of 2009. The sooner we acquire the match the sooner we will be able to build a rest room, improve our heating system in the Observatory, and acquire remote observing capability. Remote observing has the potential to change and expand our programs in ways we never thought possible.

On January 14 at the Annual Meeting BPAA members will approve a slate of board members for 2009. As required by our bylaws, in December I will send all members a letter that describes the annual meeting process. In addition, current board members are committed to a succession concept that brings “new blood” onto the BPAA board. If you are a member and interested in serving, let us know. Attend board meetings to observe how we conduct business. Our board meetings are open to all BPAA members and we are always seeking talented members interested in replacing retiring board members

Detail of Jeff Brice’s digital collage, “Night Journey,” courtesy BAC

The non-profit art gallery on Winslow Way has encouraged artists to reveal the mystery and beauty of the night sky. The exhibition runs from January 2–February 3 and includes work in paint, collage, digital media, photography, and artists’ books. Details at www.bainbridgeartscrafts.org

 

 

 

 

 

 

by Stephen Ruhl

My 1958 Cave Astrola 8 inch f7

Caves are renowned for their optics and mounts. In spite of Cave Optical Company having been out of business for nearly 30 years, they still have a strong following. Recently, a 12.5 inch in mediocre condition went for $2500 on Ebay. I stopped using my Cave much after building my 14 inch with all of the wiz-bang computer control stuff. I considered selling it.

Cave recast: My frst generation portable at OSP

Then I saw an article in the August 2008 issue of Sky & Telescope about an astronomer who constructed a portable telescope to take on an airliner (“Milsom’s Terrific Travelscope”). His design utilized a single pole extending from the primary cell to hold the secondary and eyepiece. This sounded like a reasonable way to use the optics and assorted pieces of my 8 inch Cave. Now, Milsom was working with a 6 inch f 4 and mine is an 8 inch f 7. His focal length (read pole length) was 24 inches and mine was 56 inches. I was concerned that the secondary support might not have enough rigidity, but I thought it was worth a try.

So I built what I would call the first generation of my portable ‘scope and took it on this year’s vacation to Yellowstone. The ‘scope definitely had stability issues. After moving to a new position, it took about 15 to 20 seconds to settle down and moved if you adjusted the focus or bumped the eyepiece. Not acceptable. After coming home, I added an additional pole to brace the secondary prior to going to the Oregon Star Party (OSP). While this helped considerably, the ‘scope still needed improvement.

The Oregon Star Party
As star parties go, OSP has the darkest skies and is the most primitive in terms of facilities. The dark skies are its greatest advantage. The night skies are just stunning. The Milky Way is bright and beautiful, spanning the horizon. The normal conventional wisdom is the naked eye can see to magnitude 6. I swear I could see stuff down to 7.5 or 8. My plan was to do imaging, but I was having too much fun looking at faint fuzzies.

Chris and his home-made 41 inch scope. Tis was the ‘scope’s second trip to a dark site.

The completed 2nd generation portable telescope.

 

The other advantage of OSP is that it is primitive. While I do not care for portable toilets or shower trucks, it means the people at OSP are serious about astronomy and their personal avocation, be it telescope building, imaging, or observing. There is a lot of good practical experience to be had just talking to people. A good example was my neighbor at OSP: Chris had built a 41 inch ‘scope from scratch.  Now, let us redefine scratch. Chris did not go out and buy a 41 inch mirror. No, he ground it himself. Chris did not go out and buy a mirror blank. No, he cast it himself. Hard core. Basically, he determined the mirror curve, cast the curve in a kiln-specific grout, got several inches of plate glass, put the whole thing in a kiln, allowing the glass to slump and then cool over several days to anneal. The rest of the scope was made from hardware, mostly from Home Depot. His total investment was about $5000 … and about 7 years. Really hard core.

Details of the primary mirror box. Turnbuckles control the tension on each string. Each 5/8'' tent pole breaks down into 3 pieces

Of course, night is when the action is—several hundred ‘scopes with people doing imaging or observing. It is pretty easy to go from big ‘scope to big ‘scope to see objects so faint that you have never seen them before. OSP also has observer awards for lists of objects. While I was there, I completed one list and got my certificate.

During the day, OSP has other activities: a swap meet, door prizes, telescope walk, vendors, and plenty of people willing to give you their opinion of the best way to build a telescope. They also have a series of lectures. This year I listened to two: “Design of Telescope Trusses: Theory & Implementation” and “Adventures in Telescope Making or How We got Tied up in String.” The first lecturer had looked at various truss designs, concentrating on pole termination, and analyzed them with finite element models, looking at the strains actually produced under load. The second lecture was a panel discussion with a group of people who have made string telescopes, including Dan Gray, who made the first one. The two lectures dovetailed nicely and provided me some new insight with my portable telescope project.

Back Home
I went about making my portable into a string telescope with a series of tidbits gleaned from the lectures :

• Strings must not yield under tension. “450 plus” Archery bow string is preferred.
• You need multiple strands. Between 6–12 strands were suggested.
• The tension load on the string is significant. The string makes a nice musical note.
• The mounting of the strings to the telescope must be secure and rigid on both ends.
• The poles are only in compression. You want to minimize lateral forces.

Detail of the Secondary Cage. Each string consists of 10 strands of bow string which aree then wrapped  in more bow string. Tis protects and keeps the individual strands together when not assembled.

>Because of the string design, I had to make several changes to the secondary. In the first generation, the secondary was cantilevered. The string design requires three or more poles, so the secondary has a more conventional ring design and the primary cell box needs to accommodate the additional pole. I reduced pole diameter from 1 inch to 5/8 inch since the poles were no longer supporting a cantilevered load.

The telescope is far more stable. After moving the ‘scope, the system damps in a few seconds. Most of the residual motion appears to be in the split fork mount assembly. Additionally, the entire telescope breaks down and fits in a 24 inch x 17 inch x 10 inch plywood box, the maximum size for carry-on luggage.

I now leave the portable set up and ready to go. The scope weight is about 25 pounds and can be moved to my viewing site with one hand. The end result is that I now have a telescope that can be set up in a moments notice to do some “Gonzo” astronomy, or to use with the big ‘scope to do serious viewing or astrophotography. It turns out that I am now using my little portable more than the big ‘scope.

Comments or questions are welcome at: sfruhl@gmail.com
Links:
http://www.oregonstarparty.org/
http://www.skyandtelescope.com/news/home/27768494.html (Tony Flanders’ Sky & Telescope article on this year’s OSP.)

Audience attends to Dr. Djorgovski

by Vicki Saunders

Richard Bressler accepts a plaque from Harry Colvin

They sat in the aisles and spilled out the door to hear Dr. George Djorgovski of Cal Tech discuss the Virtual Observatory and the revolution in scientific data. Digital sky surveys have created a supernova of information—available on the Web, to anyone, at http://www.us-vo.org/. The audience

Dr. Djorgovski

was riveted by Dr. Djorgovski’s presentation, which ranged from mysteriously expanding stars to the challenges of extracting useful knowledge from petabytes of data. The piece of the Big Picture that now hangs in the back of the BPAA meeting room is the direct result of a digital sky survey lead by Dr. Djorgovski. The full, stunning, image is 20 feet high and 152 feet long, an accurate rendition of a scientific data set that contains millions of galaxies, hundreds of thousands of stars, and reveals objects up to the edge of our visible universe. Griffith Park Observatory displays all 114 panels in its great hall. Bainbridge Islander Richard Bressler has generously donated a duplicate of one of the panels to BPAA.

by Malcolm Saunders, Chief Astronomer

During late September and early October BPAA prepared a written grant proposal and made a presentation to the board of the Bainbridge Island Parks Foundation, asking for money to purchase a quality, portable, computerized telescope mount. Our proposal was one of four that were funded: we were awarded $4000 to purchase a Losmandy G11 telescope mount with a Gemini servo control system. This is a quality, versatile, portable mount. Paired with any one of several telescopes that BPAA already owns it will substantially expand our capabilities.

The Losmandy G11 mount can carry up to 60 lbs of instruments.  Even with a camera attached this is plenty of capacity to accommodate a good telescope. It is a computerized Go-To mount—that means it can be controlled from a laptop computer and that it can reliably be pointed at faint, difficult to find objects.  While it is small enough and light enough to be portable, for transport to remote dark observing sites, it is also rigid and precise enough to be used for astrophotography. Virtually all modern astronomy is done not with an eyepiece but with some form of camera or other electronic sensor.  This will be the first BPAA mount, other than the permanently installed Ritchie telescope, suitable for this use.

The mount will help star party visitors, including children and the disabled, to find and see astronomical objects. Under adult supervision, children will be able to guide telescopes through the familiar interface of computer keyboard and screen.

So when, you might ask, will you be able to see and use this telescope mount?  Expect the new mount to be featured at a member meeting during the next few months. After that we should be holding a tutorial session in its operation.  When clear skies return, it should begin making appearances at our regular star parties, equipped with a real-time camera and a TV monitor. The mount will also be available as a loaner telescope for suitably-trained members to check out.

Calendar & Notes­: The Winter Sky Awaits Us
Seeing Stars: The Moon’s Phases
President’s Message: Grants Received and Pending
  New Logo, New Newsletter Design, New Era
  “The Night Sky” at Bainbridge Arts and Crafts
Renewing an Old Telescope (With the Help of OSP)
  Standing Room Only at the Big Picture Talk
BPAA gets a Quality Portable Go-To Mount

BATTLE POINT ASTRONOMICAL ASSOCIATION
P.O. Box 10914, Bainbridge Island, WA 98110
http://www.bpastro.org/
Ritchie Observatory, Battle Point Park
(206)842-9152

Officers
Harry Colvin, President
(206)842-6617, hcolvin1@comcast.net

Mike Browning, Vice President
(206)861-1630, bjjm@qwest.net

Russell M. Heglund, Secretary
(206)842-8758, rmheglund@yahoo.com

Frank Schroer, Treasurer
(206)842-1974, frank@schroer.net

Nels Johansen, Facilities Officer
(206)842-7968

Stephen Ruhl, Education Officer
(206)855-7883, education@bpastro.org

Malcolm Saunders, Chief Astronomer
(206)780-1905, astronomer@bpastro.org

Founders
Edward M. (Mac) Gardiner
President Emeritus/Founder
(206)842-3717, macg@bainbridge.net

Ed Ritchie, Chief Astronomer/Founder 1993-1997

John H. Rudolph, Facility Director/Founder 1993-2003