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Editor's Corner...

Members attending the June 13 meeting approved without dissent our proposed offer of $1,000 towards maintenance of the Spitz Planetarium. The offer has been presented to Dr. Theresa McRae, Interim Head of the Math/Science Division with current oversight responsibility for the Clever Planetarium.

Dr. McRae is a strong proponent of restoring the facility to full functionality as an important college and community resource. However, the needed expenditures will have to be approved by those who manage the college budget. It remains to be seen how long a process that will be. Our offer in support of that effort is on record. Our contribution will be paid when the maintenance work is approved and initiated.


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How many of you saw the solar eclipse on June 10th? Rosemary and I and our neighbors watched it from our back patio, viewed through the C8 with solar filter. Quite a show, with about 72% of the diameter eclipsed at maximum here in Stockton.

Jeff Baldwin was in Forks , Washington at the time. (See map on page 4 of newsletter). He took this picture at maximum, which at that higher latitude was less than 50%.

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August 8 Program:

We are pleased to welcome back NASA astrochemist Doug Hudgins, who was our guest speaker in July 2000. Doug has been a member of the SAS since that time. His success as a space scientist has grown out of his love of astronomy. He has been an active amateur astronomer and telescope maker since the age of twelve, and has been a regular at our ATM sessions for the last couple of years.

Doug's talk at the August 8 meeting will draw from both his professional work and his amateur observing experience:

The Top Ten Infrared Objects You Can See Through Your Telescope

"The infrared universe is very different from the one we see in visible light. The universe of visible light is dominated by stars; the infrared universe is dominated by glowing clouds of gas and dust that permeate every corner of our galaxy. Dark interstellar clouds that appear black as pitch to our eyes and blot out any background stars, light up like Christmas trees, blazing brightly in the infrared. The stars that are so familiar to us as we gaze at the sky, disappear or fade into the background, overwhelmed by the bright glow of the interstellar matter. Even objects that can be observed at both visible and infrared wavelengths, such as the Great Nebula in Orion (M 42) may take on very different appearances in these two regions of the spectrum.

In this talk, we'll explore 10 astronomical objects-objects that you can enjoy observing through your own telescope-that are interesting and beautiful at both visible and infrared wavelengths. We'll take advantage of the great advances that have occurred in infrared imaging over the last decade to compare these objects' appearances in the infrared to the way they appear in the visible region of the spectrum, and consider why they are similar and why they are different."


SAS Observing Program

Even if you haven't yet made friends with the major constellations, you can't go far wrong in the summer skies. Just point your scope anywhere in the Milky Way and you'll surely find something of interest.

M17, the Swan Nebula (CCD image)

This is the best time of year to linger on the showpiece nebulae in Sagittarius-M8, the "Lagoon Nebula," M20 the "Trifid," and the multi-named M17, the "Horseshoe," "Omega" or "Swan Nebula." Take your pick.

Sagittarius is the southernmost zodiacal constellation, lying between Capricornus to the east and Scorpius to the west. It plays host to the Sun at the winter solstice, but offers its best observing opportunity during these midsummer months. It is an area rich in globular clusters. Last month we mentioned M22, the globular cluster near the top of the Teapot. But there are many others. M28 is a very condensed glob. about 1° NW of l Sagitarii. Look for M54, M70 and M69 along the base of the Teapot. Also, about 10° ENE of the Teapot is M75, probably the most open of the large globular clusters.

North of Sagittarius is the small constellation Scutum, the Shield. M26 is a course open cluster, while M11 is a "semi-globular" open cluster.

Aquila the Eagle provides a fertile hunting ground for double star aficionados. Browse the area for doubles in various pale shades of yellow, blue, green and lilac.

High overhead, look for another loose glob., M71 in Sagitta, about 3° S of the "Dumbbell," M27 in Vulpecula. Then swing NW via the gold-blue Albireo to M57 the "Ring Nebula" in Lyra.

The "North American Nebula" in Cygnus is easily missed if you're glued to your telescope eyepiece. It's a huge object that is difficult to recognize in partial views. Try very low magnification or, better yet, binoculars.

So much to see, so little time! Browse slowly along the arch of the Milky Way. Make your own "discoveries" among its many treasures, then go to your charts to identify them. It's a fun way to spend the night.

...Eric Reichenbach

Perseid Meteors August 10-15

According to the August issue of Sky & Telescope, this should be a good year for the Perseids. The shower lasts about two weeks, with the peak in the predawn hours on August 12 & 13. The crescent Moon will set early enough to leave the sky dark to see 60 or more per hour.

Latitude vs. Dark Skies
by Jeff Baldwin

Glenda and I have land near Beaver, Washington, and will some day move there. Beaver is at 48° N, which is 10° farther north than Stockton. I thought it might be interesting to compare California sky conditions with what we can expect on the Olympic Peninsula.

The astronomical skies will be different. Constellations that are low in the southern sky here will no longer be visible. The many clear nights that we enjoy here in N. California will diminish to a few, extraordinarily dark nights up north.

There is also a significant difference in the number of hours of darkness between the two sites. Using TheSky software, I was able to compare the two fairly easily.

On the summer solstice, around June 21st, the Sun will be above the horizon for 14 hours 48 minutes in Stockton, and 16 hours 4 minutes in Beaver. However, that doesn't mean that the difference between the two is the difference in viewing hours.

The setting Sun goes down and to the right in northern latitudes. The farther north we go, the shallower the angle between the Sun's path and the horizon. The center of the Sun has to be 18° below the horizon for the sky to become fully dark (end of astronomical twilight), and since it goes down at a shallower slope in Washington than in California, it takes longer for the Sun to reach 18° below the horizon. So twilight after sunset (and before sunrise) lasts longer in Washington than in California, significantly reducing the period of full darkness.

I used TheSky to determine what times the Sun was at 18° below the horizon on June 21, and that left Stockton with 5 hours 20 minutes of full dark, and Beaver with only 1 hour 14 minutes!

You'd think that Beaver would get revenge in the winter, but it isn't so. The main reason is that the Sun goes down more directly in the winter, and the difference is similar to the sines of these angles (between the Sun's path and the horizon), the two being very close. At the winter solstice, Stockton has 11 hours 19 minutes of full dark, where Beaver has 11 hours 50 minutes of full dark-not much difference-even though the difference in Sun-above-the-horizon time is larger, 9 hours 32 minutes for Stockton, 8 hours 35 minutes for Beaver.

So, the spin of who has the better skies for observing shouldn't be determined by latitude if you're looking for number of dark hours. Keep in mind that there are 10 degrees of southern sky that Washingtonians can't see due to their more northern latitude, and the stuff they can see way down there is in the low, blurry part of the sky. NGC 253 is high and clear in California, and it's in the goo in Washington.

One nice thing in Washington's favor: From Stockton we drive 100 miles to our high-altitude site to observe under dark skies, yet we can still see city lights. In Washington, the skies are very much more black, and it only takes a few minutes to get to where you can enjoy them. In the city of Pullman, WA, I have seen Uranus naked eye. At magnitude 5.8, that's pretty good for standing in a city. I admit that it was at the edge of the city, but still...we can hardly see Uranus naked eye from Peddler Hill.

California enjoys about a 73% clear sky average, where Washington deals with about 73% cloudy sky average. It can vary considerably, depending on where you are. There are two rain shadows (regions of relatively low rainfall that occur downwind of a mountain or mountain range) in Washington, one at Sequim (pronounced Skwim) on the Olympic Peninsula, and the other in Goldendale, 12 miles north of the Columbia River Gorge near Biggs Junction and The Dalles. Even these areas are still very cloudy compared to California standards.

Lastly, there is one more difference between the two skies. In California, sightings of the Aurora Borealis are perhaps a three-to-four-times-in-a-lifetime experience, if you're lucky. In Washington, the Northern Lights are seen frequently. It gets to the point where you put your telescope away because the Lights are so intrusive. Growing up in Washington, I took them for granted. Now I'd do anything to see them again.

Clear Skies!...Jeff

Friday, July 19, 5pm - 10pm
Saturday, July 20, 9am - midnight
Veterans' Memorial Center
203 E. 14th Street, Davis, California

The Davis Star Show, a festival of astronomy and related sciences, is a public celebration of our universe. We will have speakers talking about exciting new discoveries in astronomy, a trade show featuring instruments and accessories appealing to a wide range of amateurs, an exhibit hall with displays and activities for all ages, daytime viewing of sunspots and other solar activity, a planetarium for the kids, astronomy club booths and demonstrations, a teacher/educational literature table, workshops, a lunar observing party at night on the 19th and a public star party at night on the 20th. The festival is free to all who wish to attend.

GUEST SPEAKERS (times are posted on the Davis Star Show Webpage at http://www.DavisStarShow.org)

Andreas Albrecht, University of California, Davis: "What do we know about the Universe?"

Steven Stahler, UC Berkeley, Radio Astronomy Group: "How Stars are Made"

Phil Plait, Sonoma State University & BadAstronomy.com: "Bad Astronomy: The Moon Hoax"

Stephen James O'Meara, contributing editor, Sky & Telescope Magazine: "The Trials and Tribulations of a 19th-Century Astronomer living in the 21st Century" and "Volcano Moon: Does the Moon's Gravity Affect Volcanic Eruptions?"

Tony Hallas, Hallas Digital Systems: "Astrophotography from the Foothills of the Sierra"

Robert Naeye, editor, ASP Mercury Magazine: "Solving the Universe's Mysteries Through Extra Dimensions"

Kent Cullers, SETI Institute: "SETI and Astronomy from DC to Daylight"

The exhibit hall will have displays by commercial vendors such as TeleVue, Lumicon, Stellarvue, Sky Publishing, Star Safaris and Hallas Digital Systems. Interspersed will be wares, displays and activities presented by our non-profit participants such as the Astronomical Society of the Pacific, Explorit Science Center, the International Dark Sky Association, the Sacramento Valley Astronomical Society, and many others, as well as by our other sponsors. There will be an educational literature table with handouts suitable for classroom instruction provided by the NASA-Goddard Space Flight Center, NASA-Ames and the Center for Science Education-Space Sciences Laboratory-UC Berkeley.

Other activities especially for our younger guests continuing throughout Saturday include a model workstation presented by the Davis High School Astronomy Club, a telescope making workshop by Melanie Smith with the SVAS, a Solar System Measurement Workstation by Steve Howe of the Elk Grove School District GATE Program and a planisphere making table run by the Explorit Astronomy Club. We will have regularly scheduled planetarium shows presented throughout the day on Saturday by S.C.O.P.E. There will also be several childrens lectures throughout the day. On Saturday, a rocketry demonstration will take place on the fields behind the Vets. Food booths will be available on Saturday for those who wish to have lunch and/or dinner at the event.

For the telescope owners wishing to know more about adjusting their own instruments, Shneor Sherman will conduct a reflector collimation workshop.

Members of the Chabot Space and Science Center will conduct a telescope making demonstration Saturday afternoon, and Chuck Pullen of the AAVSO will conduct a workshop in variable star observing. Tony Hallas's talk on astro-photography Saturday was also scheduled with the experienced amateur in mind, although his slide show of images will be enjoyed by one and all.

While the sun is in the sky, there will be solar telescopes set up outside the exhibit hall where visitors can safely see sunspots, flares and prominences. A lunar star party will be held on Friday night to enjoy the moon which will be in 2nd quarter during the event. At the public star party Saturday night we will have as many as 80-100 telescopes set up on the field so that all visitors get the chance to see the many different wonders of the night sky. In addition to the moon, you might see double stars, open and globular star clusters, bright nebulae, remnants of exploded stars, and distant galaxies. There will be people operating each of the telescopes to help you understand what you are looking at.

If you own a telescope and would like to volunteer to help out with the public star party Saturday night, please contact Jane Smith at jesmith@ucdavis.edu or telephone (530)758-4104 evngs/wknds.

Those who would like to volunteer to help with any aspect of the show itself, even if only for a couple hours, should contact Larry Snyder at ldsnyder@dcn.davis.ca.us.

For all other questions email Jane Smith at jesmith@ucdavis.edu, visit www.DavisStarShow.org, or phone (877)713-2847. For information about lodging, you may phone our host hotel, the Hallmark Inn, at 1-800-753-0035.

Please check the Davis Star Show webpage at http://www.DavisStarShow.org for the latest program updates, including a schedule of the entire event.

Greetings from the foothills of Northern California

Starry Starry Nights in the Foothills

7 Nites from 7 Sites
Wednesday August 28 through Tuesday September 3

An ambitious and impressive series of star parties will be held in the foothills area of Northern California during Labor Day Week. The public is invited. Astronomers are invited to join in to share the heavens through their telescopes.

We will be at a different dark-sky site each night. We'll be highlighting the wonders of the Milky Way. The Colfax Greater Area Chamber of Commerce is sponsoring it and handling the publicity and logistics. I am responsible for finding the sites and organizing the astronomy end of it.

We begin at the Sugar Bowl Ski Resort and through the week we'll appear in the Foresthill area, Colfax, Big Bend, Dutch Flat and Soda Springs.

Astronomers who are willing to participate by showing the heavenly sights through their telescopes are asked to contact me in advance. Those coming through the Colfax area during that week are invited to an informal open house at my home and observatory.

Don Machholz - (still comet hunting and Messier Marathoning in the foothills)
(530) 346-8963

Web sites:
Starry Starry Night page: http://www.geocities.com/donmachholz/index.html
Colfax Greater Area Chamber of Commerce: http://www.colfaxarea.com/

September 28 and 29, 2002

"The Cosmic Thread: From Stars to Life"

Is life widespread through the cosmos, or is Earth a lonely oasis? The Astronomical Society of the Pacific cordially invites you to learn more about this fascinating topic by attending its 114th Annual Meeting, a series of exciting astronomy events to be held in the San Francisco Bay Area on September 28 and 29, 2002. The theme of this year's meeting is "The Cosmic Thread: From Stars to Life."

Schedule of Events

Saturday, September 28
7:30 - 8:30 p.m.: The Society will sponsor a free public astronomy lecture by renowned comet discoverer and author David H. Levy, in the amphitheater near the summit of Mt. Tamalpais in Marin County. Levy's talk is entitled "From Stars to Life: Suppose You Had to Design a Universe?"
8:30 p.m.: A free public star party, sponsored by the San Francisco Amateur Astronomers (SFAA), follows Levy's talk. Don't worry about bringing a telescope; SFAA members will be out in force!

Sunday, September 29:  Great Talks by Leading Astronomers
The Society and the Astronomical Association of Northern California will co-sponsor a full day of lectures by some of the world's leading astronomers. We carefully selected this year's speaker lineup to focus on top-notch scientists who also excel at communicating their ideas and enthusiasm to the public. The lectures will run from 9:00 a.m. to 5:35 p.m. at Pimentel Hall on the University of California, Berkeley campus.

Scheduled speakers include:
   Alex Filippenko, ASP President, University of California, Berkeley
   Geoff Marcy, University of California, Berkeley
   Chris McKay, NASA's Ames Research Center
   David Morrison, NASA's Ames Research Center
   Jill Tarter, SETI Institute
   Chris Impey, University of Arizona
   Ben Zuckerman, University of California, Los Angeles
   Seth Shostak, SETI Institute

After the lectures, we will hold a panel discussion. The panel will take questions from the audience, and the various speakers will debate issues discussed during their lectures. Seating is limited for the lecture series, so we encourage early registration.

Admission for the lecture series is $35 general public, $30 ASP members, $25 students.

If you are an ASP member, we invite you to attend our annual members' meeting, which follows the panel discussion. Admission is free.

If that's not enough, from 7:00 to 10:00 p.m., the ASP will be hosting a reception at the UC-Berkeley Faculty Club, followed by a dinner banquet in the Heyns Room. Award-winning author and journalist Timothy Ferris will speak at the banquet. Following Ferris's talk, the ASP will present its 2002 Annual Awards, including the Society's prestigious Bruce Medal for lifetime achievement in astronomical research. Banquet seating is extremely limited, so please sign up now! Admission to the reception and banquet is $60.00. Non-ASP members are welcome to attend the reception and banquet.

For more details and for registration information, please visit the Society's website at:

Copyright © 2002 by Stockton Astronomical Society
Last Updated: 7/10/2002