Prime Focus

The newsletter of the Tri-Valley Stargazers May 1996.
Translated (roughly) from postscript into HTML for your browsing and downloading pleasure.
Keith Shank can be justly proud of this first amateur photo taken of Sharp2 2-256, 257, 255, and 258. He captured these small nebulae in Orion with a C11 at f/6.5+ST6. The single image is dark framed, flat fielded and MED'd. (AOL Image)

TVS presents

What: May general meeting
When: May 24 at 7:30 PM
Who: Phil Scherrer, project scientist with the SOHO Mission
Where: Unitarian-Universalist Church in Livermore, 1893 N. Vasco Rd.

Following last fall's lauch of the Solar Heliospheric Observatory (SOHO), its information gathering mission is well underway. Our featured speaker, Phil Scherrer, is part of the Stanford team responsible for the Michelson Doppler Imager (MDI) that is an integral tool for data collection during the mission.

The MDI generates an analysis of solar resonances by measuring energy changes across the surface of the Sun. Phil will present a miss ion update combining overheads and videos to explain the MDI and its contribution to the entire SOHO research effort.

Members of the public are always welcome at TVS general meetings, so feel free to invite anyone you believe is interested in this mission.

Final month for The Dark Site Observatory key exchange

The May general meeting is your final opportunity to exchange your observing hill key for a new one. The old lock will be permanently removed immediately following the May 24 meeting. Until that date, the old lock will remain in series with the new one so that all eligible members will have access to the observatory.

The TVS Star Party Etiquette sheet and the Tri-Valley Stargazers Astronomy Club User Agreement for The Dark Site have been published in the March and April editions of Prime Focus.
You must read the etiquette expectations, and sign the User Agreement in order to exchange your key, if you have not done so already.

If you cannot attend the May meeting, complete the User Agreement and send it with your old key to:
P.O. Box 2476
Livermore, CA 94551.
Al Smith will return a copy of the countersigned form and your new key. Your $20 deposit will be returned if you wish to relinquish your key at this time.


May general meeting
Star parties
Club news notes
What's Up in May
Comet Comments
TVS Survey
Glacier Point star parties
Membership application

Coming soon

General meeting dates:
June 28 July 26 Barbeque and Party
August 23 September 27 October 25
November 22 Decem ber 20

Open House at The Dark Site: July 6

Star Parties

The club has secured two dates for Yosemite astronomy adventures. The first will be June 21-23 (first quarter Moon). The second gives us the opportunity to enjoy Glacier Point from August 30 through September 2 (waning gibbous Moon). This is also Labor Day weekend!

Dave Anderson is coordinating the Yosemite trips, and he particularly needs members who can bring scopes over Labor Day. You can reach Dave by phone at (510) 661-4249 or via e-mail

An even more breathtaking experience awaits those who can attend the White Mountain expedition August 16-18. This high altitude site is more comfortable if you can also plan to acclimate at Grandview camp ground on the evening of the 15th.

Dave Rodrigues is coordinating use of Barcroft Lab at White Mountain. Oxygen will be available, and meals are also provided (except at Grandview). Connect with Dave at the May general meeting for more White Mountain information.

For those of you headed to the great northwest this summer, the Oregon Star Party is also scheduled for August 15-18. (Organized events end the morning of the 18th.) It will be held at Indian Trial Spring inside the Ochoco National Forest, northeast of Bend and Primeville. For registration information write to:
The Oregon Star Party
P.O. Box 91416,
Portland, OR 972 91-0416
or you can reach Chuck and Judy Dethloff at 503 /357-6163 (voice); 503 /531-7992 (fax) or e-mail to

Closer to home, TVS has a slew of local activities planned. Bob Braddy would really appreciate support for the following school and public star parties:
May 22 Donlon School 7:30 pm Pleasanton
May 28 Disney School 9:00 am San Ramon
June 8 Sycamore Grove Park 8:00 pm Livermore
July 13 Sycamore Grove Park 8:00 pm Livermore
July 19-21 Camp Shelly Dusk South Tahoe
August 10 Sycamore Grove 8:00 pm Livermore

While most of us were busy just remembering to renew our dues on time, Martin Martino took it one step further. He upgraded his membership to Patron status. Thanks, Martin, for your special support of TVS.

Joining us last month were new members Thomas Lyons and his family; as well as Mark Maral and his family.

New dome home
Herb Quick's observatory dome project is underway at The Dark Site. It will be sited downhill from the Sky Shack, below the line of sight for the 17.5 inch scope.

Construction will probably be proceeding over the next two to three months. A letter of understanding between Herb and TVS has been negotiated regarding use of the finished dome and its scope. Details will be published in a future Prime Focus.

Do you remember?
Are you the person who talked with Bob Braddy about an observing site in the future park on Brushy Peak (just north of the church)? Some stalwart TVS member approached Bob to offer help in working with the Livermore Area Recreation and Park District (LARPD). As Brushy Peak becomes as public park, LARPD is interested in preserving a portion of it for dark-sky observing. The proposed site faces northest, toward the Central Valley. If you talked with Bob, or want to work with LARPD and TVS on a Brushy Peak observing point, call Bob at (510) 855-0694.

Dave Anderson
(510) 661-4249

Earl Mack
(510) 828-1414

Vice President
Bob Braddy
(510) 855-0964

Gene Nassar
(510) 462-5986

Observatory Director
Chuck Grant
(510) 449-1500

Eyes on the Skies BBS
Mike Rushford
(510) 443-6146

Web Site

Alane Alchorn
(510) 455-9464
(510) 455-9466 fax

Meeting Location
Unitarian Universalist
Church in Livermore
1893 N. Vasco Rd.
3/4 mile north of I-580

Alane Alchorn
Dennis Beckley
George Cameron
Rich Combs
Chuck Grant
Rich Green
Al Smith

Tri-Valley Stargazers
PO Box 2476
Livermore, CA 94551

Membership: 127

17 Fri New Moon 4:46 AM Excellent weekend for observing.
18 Sat Asteroid (372 ) Palma occults SAO 1176 50 (mag. 8.7, R.A. 9h23.7m, Dec. +8° 3 8') 9:54 PM in or near Bay Area. Max. duration: 9 sec.
19 Sun Venus 8° north of Moon.
22 Wed Pluto at opposition (mag 13.7).
Donlon School star party, Pleasanton, 7:30 PM
24 Fri Tri-Valley Stargazers meeting 7:30 PM PDT. Unitarian-Universalist Church in Livermore, 1893 N. Vasco Road, Livermore. (3/4 mile north of I-580 ).
Riverside Telescope Makers Conference begins, Big Bear City, California.
25 Sat First Quarter Moon 7:13 AM
27 Mon Memorial Day
28 Tue Disney School slide show and talk, San Ramon, 9 AM
29 Wed TVS Planning Meeting 7:00 PM Circle Wing, 184 Airway Blvd., Livermore. (Call 455-9464 for information or directions.)
30 Thu Asteroid (1) Ceres at opposition (mag. 7.0).


1 Sat Full Moon, 1:48 PM
8 Sat Last quarter Moon, 4:06 AM
Sycamore Grove Park star party, Livermore, 8:00 PM
15 Sat New Moon, 6:37 PM
21 Fri Glacier Point, Yosemite star party begins
Astronomical Society of the Pacific annual meeting begins. Westin Hotel, Santa Clara.

Some late-springtime deep-sky objects M81 & M82 Two fine galaxies in Ursa Major. The first is a fine spiral; the second is irregular and elongated, with a dark band running through it.
M97 & M108 The Owl Nebula and a nearby galaxy. M97 is a large, somewhat faint, planetary in Ursa Major.
M65 & M66 Two nice galaxies in Leo with the large, fainter, edge-on spiral NGC 3628 in the same field.
M95 & 96 & 105 A triplet of galaxies less than one degree apart in Leo.
M51 The Whirlpool Galaxy in Canes Venatici, one of the best galaxies in all of the sky. Peculiar appendage NGC 5195.
M3 A fine globular cluster in Canes Venatici.
NGC 3242 The Ghost of Jupiter in Hydra, a nice planetary.
M104 The Sombrero Galaxy in southern Virgo.
M58, 59,60, 84, 86, 87, 89, 90, etc. The Virgo Cluster! A swarm of mostly fair ly faint galaxies of all sorts. For an excellent star-hopping tour of the heart of the cluster, see Alan M. MacRobert's, "Mastering and Virgo Cluster", Sky & Telescope, May 1994, pp. 42-47.
3C273 The brightest, and first-discovered, quasar, in Virgo. Difficult at mag. 12-13. (Red shift 0.158 )
M13 The Great Hurcules Cluster! Look for the mag. 12 galaxy NGC 6207 in the same field.
M92 Another fine globular cluster in Hercules., often overlooked.

What's Up in May

by Dave Anderson and others

Comet Comments, May 1996

C/1995 Y1 (Hyakutake)
DATE (00UT) R.A. (2000) DEC El. Sky Mag
05-17 23h31.6m +35° 33' 56° M 11.3
05-22 23h39.7m +36° 05' 58° M 11.5
05-27 23h47.0m +36° 34' 60° M 11.7
06-01 23h53.6m +37° 00' 62° M 11.8
06-06 23h59.4m +37° 24' 65° M 12.0

C/1996 B1 (Szczepanski )
DATE (00UT) R.A. (2000) DEC El. Sky Mag
05-17 09h35.1m -21° 39' 97° E 11.5
05-22 09h39.7m -22° 43' 94° E 11.8
05-27 09h44.6m -23° 43' 92° E 12.0
06-01 09h49.9m -24° 42' 89° E 12.2
06-06 09h55.6m -25° 38' 87° E 12.4

C/1995 O1 (Hale-Bopp)
DATE (00UT) R.A. (2000) DEC El. Sky Mag
05-17 19h38.6m -16° 03' 123 ° M 7.3
05-22 19h35.8m -15° 37' 128 ° M 7.2
05-27 19h32.5m -15° 11' 133 ° M 7.1
06-01 19h28.6m -14° 44' 139 ° M 6.9
06-06 19h24.2m -14° 17' 144 ° M 6.8

22P/ Kopff
DATE (00UT) R.A. (2000) DEC El. Sky Mag
05-17 18h51.0m -15° 49' 134 ° M 8.1
05-22 18h57.2m -15° 46' 137 ° M 7.9
05-27 19h02.4m -15° 46' 140 ° M 7.7
06-01 19h07.2m -15° 51' 144 ° M 7.5
06-06 19h11.2m -16° 00' 148 ° M 7.2

C/1996 B2 (Hyakutake)
DATE (00UT) R.A. (2000) DEC El. Sky Mag
05-17 02h31.9m -02° 29' 27° M 3.3
05-22 02h41.5m -09° 12' 35° M 4.1
05-27 02h53.2m -15° 47' 42° M 4.8
06-01 03h06.7m -22° 21' 50° M 5.3
06-06 03h22.2m -28° 55' 57° M 5.8

95P/ Chiron
DATE (00UT) R.A. (20 00) DEC El. Sky Mag
05-17 12h27.1m -05° 13' 132° E 15.5
05-22 12h26.6m -05° 06' 127° E 15.5
05-27 12h26.3m -05° 01' 122° E 15.6
06-01 12h26.2m -04° 57' 117° E 15.6
06-06 12h26.2m -04° 55' 112° E 15.6

by Don Machholz
Comet Hyakutake (C/1996 B2) performed well as it passed by Earth in late March. Not only did it shine brightly, but bits of material were blown off the nucleus while the tail stretched for over 70 degrees. It has been a most memorable comet! It will reach its closest point to the sun on May 1, then becoming an exclusively Southern Hemisphere object, with two possible exceptions. First, it may be visible in daylight through a telescope to experienced observers who take the proper precautions to avoid pointing their instrument at the sun. Secondly, the comet's tail may be seen rising at morning twilight between roughly April 28 and May 7. A long tail will point toward the northern part of the constellation Triangulum on April 28, swinging southward during the next week until it points toward the planet Saturn (due east) by May 7.

Comet Hale-Bopp passes behind the moon on the morning of May 8. This rare lunar ooccultation will be visible at roughly 09hr UT from the western United States, Mexico and Central America. Meanwhile, several other comets are visible, including the faint Comet Chiron, which has just reached periheli on in its 50-year orbit. It will appear nearly stellar since it is 7 AU away and rather inactive. It was once thought to be an asteroid.

C/1996 E1 (NEAT): This comet was discovered at magnitude 16. on March 15 by the Near Earth Asteroid Tracking Team. It reaches perihelion in July at 1.35 AU. It may brighten to magnitude 14 by then.

Orbital Elements
Object Hyakutake(95Y1) Szczenpanski Haykutake(96B2)
Peri. Date 1996 02 24.28973 1996 02 06.89903 1996 05 01.40305
Peri. Dist (AU) 1.054576 AU 1.4486192 AU 0.23014060 AU
Arg/Peri (2000): 046.35126 deg. 151.27225 deg. 130.18992 deg.
Asc. Node (2000): 195.75924 deg. 345.44413 deg. 188.05114 deg.
Incl (2000) 054.46584 deg. 051.90616 deg. 124.90012 deg.
Eccen: 1.0 0.9899357 0.9998449
Orbital Period: Long Period 1727 yrs. 57,000 yrs.
Ref: MPC 26543 MPEC1996-C02 (2-26) MPC26724 (02-27)
Object Hale-Bopp Kopff Chiron
Peri. Date 1997 04 01.14561 1996 07 02.19980 1996 02 14.95655
Peri. Dist (AU) 0.9140971 AU 1.5795617 AU 8.4539538 AU
Arg/Peri (2000): 130.59227 deg. 162.83487 deg. 339.56390 deg.
Asc. Node (2000): 282.47087 deg. 120.91329 deg. 209.38406 deg.
Incl (2000) 089.42807 deg. 004.72143 deg. 006.93041 deg.
Eccen: 0.9950784 0.5440739 0.3828750
Orbital Period: 3000 yrs. 6.45 yrs. 50.70 yrs.
Ref: MPC26879 (3-26) MPC22032 (1991) MPC22797 (1993)

Tri-Valley Stargazers Annual Survey - 1996

How did you find out about the club?
S&T Lumicon Friend LLNL Usenet Member Other
3 12 0 2 0 9 2
Are we meeting your expectations?
Yes No
30 0
How long have you been a club member?
<1 year 1-3 years 3-5 years over 5 years
2 12 11 8
How often do you attend monthly meetings?
Always 50% Occasionally Never
11 3 11 7
How often do you go to The Dark Site?
Several times a month Once a month Every 2-3 months 1-3 times a year Never
1 4 4 15 9
Do you have a computer?
Yes No Mac IBM/Clone
29 5 8 22
Do you have a modem?
Yes No
24 5
Have you signed onto the buletin board?
Yes No
12 18
Have you borrowed books from the library?
Yes No
11 22
Are you willing to help with school programs?
Yes No
9 16
Activities ranked in order of importance
Ranked #1 Ranked #2 Ranked #3 Ranked #4 Ranked #5
Meetings/Speakers 12 10 3 0 4
Star Parties at The Dark Site 12 6 7 2 2
Public Star Parties 5 8 8 5 2
Yosemite/White Mountain 9 7 5 4 4
Obvserving/ Fremont Peak 4 4 10 5 3
Amateur Telescope Making 5 6 6 5 5
CCD Imaging 4 4 6 7 7
Astrophotography (fi lm) 8 5 3 8 4
Deep-sky observing 19 5 3 2 2
School programs / presentations 1 4 10 8 2
Computer - Internet - BBS 4 6 7 5 5
Future Meeting Topics Ranked A Ranked B Ranked C Ranked D A+B C+D
Cosmology 11 4 7 1 15 8
Stellar Evolution 7 8 5 2 15 7
Planetary Science 9 10 2 1 19 3
Sun 6 11 8 0 17 8
Moon 4 12 6 2 16 8
Lunar & Planetary Observing 8 11 3 1 19 4
Deep-sky Observing 17 7 1 0 24 1
Astrophotography 13 6 5 1 19 6
Filters 5 10 8 0 15 8
Collimation Scopes/Optics 14 8 3 1 22 4
CCD Astronomy 7 4 11 2 11 13
Telescope Accessories 8 9 6 1 17 7
Archaeoastronomy 6 5 7 5 11 12
Scope Making 8 7 6 4 15 10
Open House/Public Observing 8 6 6 1 14 7
Meteors & Comets 10 8 4 1 18 5
Astro Computing 8 4 7 5 12 12

Tri-Valley Stargazer Annual Survey - 1996 (cont.)

Scanning the 1996 survey

Thank you to all the members who completed 1996 survey forms. The board will use your input in planning speakers and activities through the end of this year. If you were unable to complete a survey, and have an opinion to share, collar any board member at the next TVS function and let your thoughts be known.

Future meeting topics will be chosen from the most- requested ones on the list. They are: deep sky observing, astrophotography, scope collimation and optics, lunar and planetary observing, planetary science, and meteors and comets. Most of these are perrenial favorites, and the board would like your help in choosing speakers who are new to our group.

Preferred astronomical activities for TVS members changed slightly this year, with deep sky observing ranking ahead of both meetings/speakers and The Dark Site star parties.

Free loaner scopes
How would you like to enjoy any of the three TVS loaner scopes free for one entire month? Sure, there is one little catch... Reserve "your" scope, and put up the refundable $50 deposit check.(It willl NOT be cashed unless you abscond with the scope.) Separately pay the $15 monthly rental. Then, share "your" scope one night that month at a TVS star party. When you return the scope, ALL your money goes back home with you. For your free scope deal, see Chuck Grant at any general meeting!

Editor's Note
The second run of "Starman" is reprinted below courtesy of amateur cartoonist/astronomer Jay Ryan. Jay observes in Cleveland, Ohio. Please let the board know if you want to see this feature continued in Prime Focus.

Yosemite trip details

The club's two Glacier Point, Yosemite, star parties are scheduled for June 21-23 (equinox weekend, with a first quarter Moon) and August 30-September 2 (Labor Day weekend, with a waning gibbous moon).

Campsites are provided by the park service in exchange for the public star parties TVS presents. Viewing can continue all night long after the public event. Campsites will be available at Bridal Veil, or another spot as designated by the Yosemite staff. If you wish to park a camper, you must arrange for your own campsite. A club barbeque will be held each Saturday night. Please bring a side dish to feed eight.

The TVS slide show for public star parties is still in need of your donated or duplicated photos. If you have slides that you can loan for either event, label them first. Then call Dave Anderson and make arrangements for him to borrow them. They will be returned if you so request.

TVS Membership Application Since November 1, 1996 we estimate that this page has been downloaded about times.

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