October 2004 2 - SDAA

CONTENTS

San DiegoAstronomy AssociationCelebrating Over 40 Years of Astronomical Outreach

Office (619) 645-8940Observatory (619) 766-9118http://www.sdaa.orgA Non-Profit Educational AssociationP.O. Box 23215, San Diego, CA 92193-3215

October 2004

SDAA Business MeetingNext meeting will be held at:SKF Condition Monitoring

5271 Viewridge CourtSan Diego, CA 92123October 12 at 7:00pm

Changes to the TDS Site Rules

by Scott Baker

Vice President

In the past few months two rules have either been modified or added

to the "Rules for the Tierra Del Sol Observing Site" document. The

most recent change, made at the September Business Meeting was to

rule four (4.) which now reads.

"4. Members and guests shall use only the minimum light necessary

for safety, and light should be red or masked in red to preserve night

vision. Lights shall be kept pointing towards the ground whenever

possible. The use of laser pointers is prohibited at all times. Laptop

computers should use a red filter and be masked or shielded so that no

stray light escapes the sides of the display. Check and be sure it is clear

to use lights before proceeding in or out of any area. Be considerate

of others and their night vision and photography efforts."(continued page 5)

Clean Up TDS & Bar-b-que!Jerry Hilburn, The Trash Guy!

Ladies and Gentlemen its time to break out the shovels and rakes,

wheel the barrels and get busy cleaning. On October 9th and October

16th we will be cleaning up TDS. The fun starts at 10AM on both days

and the goal is to get as many pieces of junk off the property as

possible, do some scraping and painting, and clean the warming room

and storage containers. We will be leasing a 40ft trash container to

haul away the junk and we need your help.

If you can come out and pitch in we plan to feed you at the close of

each days work (~ 4pm). So we are planning a bar-b-que for the

workers that come to help! We need you to volunteer. In order to

plan the meal please send a confirmation to Jerry Hilburn at:

[email protected] or call (858) 565-4059.

Program MeetingOctober 20th

Rich Strobel, SDAA Star Party Chair

November 17thAnnual Board Nominations

Mission Trails Regional ParkVisitor and Interpretive Center1 Father Junipero Serra Trail

October 2004 Vol XL, Issue 10Published Monthly by theSan Diego Astronomy Association75¢ /$8.00 yearIncorporated in California in 1963

TDS Site Rules.............................................1Astronomy 101............................................2Treasurer’s Report.......................................5Program Meeting.........................................5Sky Watch.....................................................6AISIG Update..............................................7Board Meeting Minutes..............................8Space Technology......................................10Border Lights...........................................11The Back Page...........................................12

San Diego Astronomy Association

SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, OCTOBER 2004


By Scott Baker

Delphinus, the Dolphin

According to the Greek historian

Herodotus of Halicarnassus (440

BC), there once was a famous

musician named Arion who was

the greatest singer who ever

existed. Arion worked as the

court musician and singer for

King Periander of Corinth.

Arion, anxious to share is abilities

with the rest of the known world,

decided to travel to Sicily and sing

to the people there. He wasn’t

long in Sicily before he became

quite wealthy from his abilities.

Rich and famous, he decided to

return to his beloved Corinth.

Arion booked passage on a ship,

not knowing that the crew knew

how wealthy Arion was and had

plans to take his wealth and his

life. Once far from land, the crew

took Arion on deck and were

about to kill him when Arion

beseeched them for one last

request. The request, to sing one

more song, was honored by the

crew and Arion began the most

beautiful song he had ever sung.

The song so enraptured the

creatures of the sea, that they

formed a circle around the ship,

including a school of dolphin.

Arion, seeing the dolphin and

how they so enjoyed his song, that

just before it ended, he jumped

into the sea and landed on the

Sicily, with his great wealth, but

when they saw Arion step out

from the crowd, they confessed

their plot. The King, infuriated

by their lies and deceit, had the

crew put to death. The God

Apollo, so impressed by the good

dolphin’s deed, in saving Arion,

decided to honor all dolphins by

placing them in the stars forever.

And thus, the constellation of

Delphinus was formed.

The Constellation Delphinus,

lying at the Eastern edge of the

Milky Way, is surrounded by the

larger, more famous constellations

of Pegasus, Aquarius and Aquila.

But it’s also abuts the smaller

Sagitta, Vulpecula and Equuleus.

Although small, it has a great deal

of interesting objects for the

amateur astronomer. The four

main stars of the constellation

form a rectangular asterism called

“Job’s Coffin”. This name is sort

of a mystery, but may linger from

when this part of the sky was

seen as a whale, instead of a

dolphin. In the Bible, Job was

never swallowed by a whale like

Jonah, so why “Job’s Coffin”?

Know one knows. Two of the

stars that form the asterism are

Alpha and Beta Delphini, also

known as Sualocin and Rotanev.

Have you ever heard about the

companies that will “name” a star

for you for a fee? Most are a

scam, however, one astronomer

did get his name in the stars, his

name was Nicolaus Venator. In

1814 he was the assistant director

of the Palermo Observatory and

helped create a star catalog where

these names first appeared,

Sualocin and Rotanev, his name

spelled backwards. Sly dog. The

names remain today in modern

catalogs.

Another interesting asterism is

“The Dolphin’s Diamonds”.

Really an open cluster of about 13

back of one. The dolphin, with

Arion on it’s back, raced towards

Corinth, leaving the ship and

crew, in bewilderment. When

Arion arrived in Corinth, he went

straight to King Periander and

told him of his ordeal. When the

ship arrived in Corinth, Periander

was waiting for it on the docks.

The crew explained to the King

that Arion had decided to stay in



stars, best at about 250x, forms a

sort of toadstool shape. If your

field is wide enough, you can

catch a glimpse of NGC7025 an

extremely small lenticular galaxy

at the edge of the cluster (see

below).

For the double star observer, two

are worth a look in Delphinus.

The first, Gamma Delphini, is a

wide double, which can be re-

solved by binoculars. The two

stars shine at magnitudes of 4.5

and 5.5. The second double,

harder to resolve, is Struve 2725.

The two stars are of 7th and 8th

magnitude. This double lies nearly

in the same field of view as

gamma Delphini.

For the deep sky enthusiast,

Delphinus is full of faint fuzzes;

we’ll start with a couple of

globulars. NGC6934 is a small

globular cluster, about 7 degrees

south of “Jobs Coffin”. The

cluster has a diameter of 6 arc

minutes and is about 9th magni-

tude. It can be seen with binocu-

lars, with an almost stellar like in

appearance, but small scopes will

show it as a fuzzy “nebular”

looking ball. The other globular,

NGC7006, has the distinction of

being one of the most distant

globulars in the Milky Way. It’s

about 185,0000 light years from

Earth and 150,000 light years

from galactic center. It’s located

about 3.5 degrees East of gamma

Delphini and is only 3 arc minutes

in diameter. The cluster is very

dense with a compact center.

Don’t even attempt this globular

with anything less the 6".

For the planetary nebula fan, take

a look at NGC6905, otherwise

known as the “Blue Flash

Nebula”. This is splendid little

planetary, similar in appearance to

the “Blue Snowball” in Androm-

eda, but without quite so much

color. Small scopes will see it as a

round ball, and with good condi-

tions, a hint of color. Larger

scopes are required to see the

central star and the nebulous

lobes that under high magnifica-

tion, make it appear like the

Saturn Nebula. Give this gem a

look. Another planetary, not

nearly as impressive as the “Blue

Flash”, is NGC6891. This small

round object is often overlooked

because of its near stellar appear-

ance and it’s position amongst a

field of Milky Way stars. The

surface brightness is high and easy

to observe, but difficult to find at

low power due to its small size.

For the galaxy fan, there are many,

most requiring large objectives

and dark skies to glimpse, but two

to test your scope on are NGC



Board Elections

Nominating Committee

SDAA will be holding annual

elections to the board this fall and

nominations for the following

positions on the board are re-

quested.

President

Vice-President

4 Director Positions

Recording Secretary

Corresponding Secretary

If you are interested in serving on

the board of the SDAA then

please submit a request to be

included on the ballot to

[email protected].

7025 and NGC 6988. NGC

7025, mentioned earlier, at the

edge of the “Dolphins Dia-

monds” is a 14th magnitude

galaxy appears as elliptical

smudge, nearly stellar, close to a

9.2 magnitude star. The other

galaxy, NGC 6988, is another to

test yourself and your equipment.

NGC 6988 at 15th magnitude,

will give the appearance of a

round ball at high magnifications,

this is a real challenge object.

Most of the other galaxies located

in Delphinus will also test the

largest scopes, so if you’ve got the

time and the aperture, give Del-

phinus a long look.

The Dolphin’s Diamonds

Description: Modern telescopic

asterism within Delphinus.

RA: 21h 07m 02.0s Dec:

+16°16’35" (Epoch 2000)

NGC 6891

Other description: Planetary

nebula disc.

Dreyer description: Planetary

nebula, stellar = 9.5th magnitude.

Magnitude: 12.0

RA: 20h 15m 12.0s Dec:

+12°42’00" (Epoch 2000)

Size: 1.2'

NGC 6905

Other description: Planetary

nebula disc with central star. Blue

Flash Nebula

Dreyer description: Very remark-

able!, planetary nebula, bright,

pretty small, round, 4 small stars

nearby.

Magnitude: 12.0

RA: 20h 22m 24.0s Dec:

+20°07’00" (Epoch 2000)

Size: 1.7'

NGC 6934

Other description: Globular

cluster.

Dreyer description: Globular

cluster, bright, large, round, well

resolved, stars of magnitude 16

and fainter, 9th magnitude star

westward.

Magnitude: 8.9

RA: 20h 34m 12.0s Dec:

+07°24’00" (Epoch 2000)

Size: 5.9'

NGC 6972

Other description: Round galaxy.

Dreyer description: Faint, small,

round.

Magnitude: 14.0

RA: 20h 50m 00.0s Dec:

+09°54’00" (Epoch 2000)

Size: 1.0' x 0.5'

NGC 6988

Other description: Round galaxy.

Dreyer description: Extremely

faint, pretty large, round.

Magnitude: 15.0

RA: 20h 55m 48.0s Dec:

+10°32’00" (Epoch 2000)

NGC 7006

Other description: Globular

cluster mottled.

Dreyer description: Bright, pretty

large, round, gradually brighter

middle.

Magnitude: 10.6

RA: 21h 01m 30.0s Dec:

+16°11’00" (Epoch 2000)

Size: 2.8'

NGC 7025

Other description: Round galaxy

with bright core.

Dreyer description: Very faint,

very small, round, stellar

(pointlike).

Magnitude: 14.0

RA: 21h 07m 54.0s Dec:

+16°20’00" (Epoch 2000)

Size: 1.6' x 1.0'



Solar and Star Party

Saturday October 9th

KQ Ranch Resort by Julian.

Amenities include: a pool, spa,

and meals (very reasonably

priced) served throughout the

weekend. We have typically had

100+ happy campers come up to

see the stars on Saturday night! If

you are interested let me know

and I will make arrangements for

you. Come up and enjoy the 5star

campground facilities on Friday

also. I will be on vacation for two

weeks starting on September 16th

and may not be answering emails

so let me know after the vacation.

Oh by the way, this is a VERY

dark sky site!

Rich Strobel

East County Star Party Coordinator

[email protected]

The other change, made several

months ago, was the addition of

rule fourteen (14), which reads...

"14. Groups, either students or

friends of members, larger then 8

in number, must be approved by

the Board of Directors, prior to

their visit. All groups, of any size,

must abide by the above rules,

must arrive before dark and must

have a prearranged departure

time. The group MUST be

instructed in white light etiquette

before the night of the visit.

Regardless of the night of the

visit, weekdays or non-star party

weekends, these rules must be

strictly obeyed. Failure to comply

with these rules will be punish-

able, as deemed necessary, by the

Board of Directors."

The rules, in their entirety, can be

downloaded from the SDAA web

page at www.sdaa.org or from the

SDAA Yahoo Group [Files]

section. I encourage all members

to review these rules before your

next visit to the site.

Treasurer’s Reportby Michael Finch

With the addition of our new

members we now have a total of

610 SDAA members. We added

several new members last month.

Please welcome David Goodin,

Patricia Hoffman, Randy

Krzyston, George Ream, Gracie

Schutze, Kerry Swinscoe, and

Cheri Wessel. Welcome to SDAA

and may you enjoy clear dark

skies!

A reminder to our members

renewing their memberships. All

memberships are for one calendar

year beginning the first of the

month (e.g., 7/1/1995). Expira-

tion dates are based on a

member’s join date, not payment

date. Renewal payments extend a

member’s expiration one year

from the last expiration regardless

of when it is paid. For example, a

member joined SDAA on 9/1/

1993. The member renewed on

7/14/2004. The member’s new

renewal date is 9/1/2005. An-

other example, a member joined

SDAA on 4/1/2001 and renewed

on 6/4/2004. The new expira-

tion date is 4/1/2005. Please

contact me by e-mail

([email protected]) if you have

any questions. Thank you.

Please note that Sky & Telescope

Magazine can only be renewed for

one year at a time. The publisher

does not have a 2 or more year

renewal rate.

Second Site Fund balance:

$5,192.79

Changes continued from page 1

Program Meetingby Scott Baker

The September program meeting

drew about 40 members to see

the second half of the DVD

"Universe - The Cosmology

Quest", followed by a trailer for

the new Nova program "Origins".

Although the Universe DVD was

a bit of a let down, the Nova

Trailer was fascinating and piqued

everyone's interest to watch the

four-hour program. The big

raffle winner was Jose Magsaysay,

who took home the Starbound

Observing Chair. I want to thank(continued page 7)



SkyWatch for October, 2004

John Mood

[ Times PDT]

[ * = 1 star = EZ ] [ ** = 2 stars = Moderate ] [ *** = 3 stars = Difficult ]

Sun., 3 Oct. —— VENUS is less than a half degree from REGULUS before dawn this morning(see below).

Sat., 9 Oct. —— PUBLIC STAR PARTY @ Tierra del Sol. There will be a work party during thedaytime to clean up the site at TdeS & a bar-b-q for those who do work (no free lunch!).

Wed. 13 Oct. —— NEW MOON, 7:48 p.m.; a PARTIAL SOLAR ECLIPSE is visible today if you’rein Hawaii, Alaska or Japan (where it will be the 14th!).

Sat. Oct. 16 —— “New Moon Night.”Sat., 23 Oct. —— PUBLIC STAR PARTY @ Tierra del Sol; explore the Moon’s “terminator”

(where dark turns to light) for spectacular views of mountains, craters & rills.Wed., 27 Oct. —— FULL MOON, 8:08 p.m.

—— TOTAL ECLIPSE OF THE MOON; totality begins 7:23 p.m. & ends at 8:45p.m., partial ends at 9:54 p.m. & penumbral ends at 11:03 p.m. This is the last totaleclipse of the moon visible anywhere in the world ‘til 2007 so don’t miss it!

Note that the penumbral phase of the eclipse will already have begun before themoon rises. Specifically, sunset is at 6:02 & moonrise is a few minutes earlier at 5:54. The partial phase of the eclipsebegins at 6:14 so you should be able to spot it ifyou have a clear view of the eastern horizon.

Another factor is twilight. The USNO (U.S. Naval Observatory) defines “civil twilight” as the sun being 6degrees below the horizon with terrain & horizon still visible (6:27 on the 27th). “Nautical twilight” is the sun 12degrees below a now hardly visible horizon (6:56 on the 27th) & “astronomical twilight” is the sun 18 degrees belowthe horizon with darkness complete (7:25 on the 27th). Thus, the startling & lovely contrast between the silvery fullmoon & the pumpkin-colored fully eclipsed moon will not be as dramatic for us here in San Diego at the beginningof the eclipse as it will at the end. So sit it out!

Sun., 31 Oct. —— Daylight Savings Time ends; move clocks back an hour this morning. —— HAPPY HALLOWEEN tonight!

EVENING PLANETS:There are no naked eye planets visible in the evening. {Boo! Hiss!} However, NEPTUNE [ ** ] in Capricornus the

Goat & URANUS [ * 1/2 ] in Aquarius the Water Carrier are now visible fairly high in the sky. They require telescopes toresolve their discs, but you sharp-eyed younger viewers can spot Uranus naked eye if you have a good finder chart. {I used tobe able to myself!}

MORNING PLANETS:SATURN [ * ] is in Gemini the Twins & is high in the sky before dawn. VENUS [ * ] crosses from Leo the Lion (see

above for its close pass of Regulus on the 3rd) into Virgo the Virgin. JUPITER [ * ] is also in Virgo & daily (nightly!) getshigher in the sky, & thus more available for telescopic viewing, as the month goes on. Jupiter & Venus will pass each othernext month. Late in the month, MARS [ * 1/2 ], likewise in Virgo (I wonder what astrologers make of all this planetaryactivity in Virgo!), can be spotted low on the horizon next to Spica shortly before dawn breaks, providing a nice white contrastwith ruddy Mars.



{ N.B. Because of the recent discoveryof 2 relatively large trans-Neptunianobjects, many professional astronomersno long consider Pluto a planet. I’ll goalong with them! }

TIERRA DEL SOL LAT = 32º 36' 48" N ( ±0.l” ), LONG = 116º 19' 55" W( ± 0.1" ), ELEV = 3710'( ± 5' ), at the bathroom, asdetermined from USGS 7.5min 1/24000 map.

Send comments & questions tome by phone (619/225-9639),USPS (4538 Long Branch Av.,San Diego, CA 92107) or mye-mail address([email protected]).

¡HAPPY VIEWING!

AISIG UPDATEby Jerry Hilburn, AISIG Chair

The October AISIG meeting will be held at 4 PM in the warming room at TDS on October

16. We are hoping to have a Meade DSI available for that meeting and will have a follow on

demonstration at Observatory 7 between 9 and midnight. With the installation of the fire

suppression tank and the recent work completed on critical infrastructure the time has come

for the AISIG group to restart the AISIG imaging area project. We need a big turn out to get

this project going. We will be reviewing site plans and selecting a layout for the new area at this

meeting. Please plan to attend the meeting on the 16th.

The AISIG site is off to a great start and we now have over 120 images for the public to view

at http://aisig.sdaa.org. If you have not visited the site please take a few minutes to go look. I

am sure you will be amazed at the work the AISIG group has posted. If you haven't signed up

to post pictures, there is no time like the present to get going. My goal for AISIG is to have

over 5000 pictures online by the close of 2005. The AISIG site is unique and I have yet to find

anything quite like it among the other club sites that I have visited on the Internet. So far since

the site opened we have had over 2000 unique visitors. Lets get busy posting!

OPT and Mike Fowler for selling

us the monthly prizes at their

cost.

The October meeting, on the

20th, will feature our own Rich

Strobel, who has put together a

presentation on our public out-

reach star parties. So make sure

you attend and see some of the

great photos of people and

members enjoying our star party

program and learn how you too

can help this great cause.

The monthly program meetings

are held at the Mission Trails

Regional Park Visitor Center

Program continued from page 4 Theater on the third Wednesday

of each month. The doors open

at 6:30 and the meeting starts

promptly at 7:00. Directions to

the Visitor Center can be found

on the MTRP web page at

www.mtrp.org.

SDAA Editorial StaffEditor

Douglas [email protected]

Contributing WritersScott BakerMike FinchJohn Mood

Jerry HilburnPatrick L. BarryDr. Tony Philips

Craig Ewing



SDAA Board MeetingMinutes, September 14, 2004

The Board meeting was called to

order at 7:14 PM. In attendance

were Michael Dietz, Daryel

Stager, Rich Strobel, Michael

Finch, Jerry Hilburn, Bill Griffth,

Brian Mc Farland, Brian Staples,

Christopher Watson, Jim Traweek,

Allen Pellymounter, Joshua

Johnson and Scott Baker.

The TDS Site Report was giving

by Bill Griffith: Well and new

pump are in good shape, present

recovery rate is ¾ gallon a minute.

The pump and well company that

did the work recommended a

secondary tank be installed for

potable water storage. A tank in

the area of 2,500 gallons would

be adequate for our application.

A motion was made to allocate

$2,500.00 for the new tank. This

was seconded and approved.

The septic tank was pumped on

Monday the 13th. The system,

having never been pumped

before, was full, but was in good

condition. The tanks our located

just East of the shower enclosure.

New lids are required, due to the

destruction of the first set in their

removal. The work party/barbe-

cues scheduled for the 9th and 16th

of October are on schedule.

Dumpsters will be ordered and be

on site for those weekends. A

motion was made to allocate

$200.00 for the barbecue food

and supplies. This was seconded

and approved.

Observatory Report by Jim

Traweek: Jim checked the roof,

motor and chain for any possible

problems after reports of trouble

with the roof control. He tight-

ened a loose drive chain, inspected

all, and determined all is in good

working condition. Jim requested

funds to insulate the Eastern and

Southern walls of the observatory,

as was done for the Western wall

recently. A motion was made to

allocate $400.00 for this. This was

seconded and approved.

Private Pad Report by Brian

McFarland: Two pads that had

returned to club have been issued

to members on the waiting list.

Two more pads are due back and

will be issued to the next two

members. Bob Oxley submitted

plans for his private pad. These

were reviewed and approved by

the Board.

Star Party Report by Rich Strobel:

Joshua Johnson has volunteered

to be the South County Coordina-

tor. The club has received

$450.00 from KQ ranch, as a

donation, for all the star parties

done there this summer. Another

star party is scheduled which raise

this total to $600.00. The San

Diego Aircraft Carrier Museum

(USS Midway) has asked for

volunteers from the SDAA to do

star parties on the ship four times

a week. The Board felt that this

was not possible, but if a volun-

teer group could be formed, once

or more a month may be possible.

Rick said he’d try and find some-

one to organize this recurring star

party.

Library Report: No Report.

Membership Report by Scott

Baker: Last Months program

meeting featured Ken VanLew

speaking on comets, and two

students presenting their science

fair projects. The September

meeting is to show the remainder

of the DVD “Universe – The

Cosmology Quest”. The October

meeting will feature Rich Storbel

taking about being a volunteer for

star parties. Scott requested

payment of $78.85 for the DVD

“Universe – The Cosmology

Quest”, so that it could be placed

in the library for members to

check out. A motion was made,

seconded and the expenditure

approved

AISIG Report by Jerry Hilburn:

It was reported that there are

currently over 30 members on the

AISIG web site, with over 100

images presently available for

viewing.

Newsletter Report by Brian

Staples: The new editor, Doug

Searles, will take over with the



October issue of the newsletter.

All submissions should go to

Doug at [email protected]. It

was suggested that we start

printing 600 copies of the news-

letter, about 50 more then usual,

so that we can start sending them

to astronomy related businesses in

the possibility of getting advertis-

ing. We will also, as a show of

good will, start sending them to

large number of clubs in the

Southwest. The increase in

printing quantities was approved.

Web Page Report by Christopher

Watson: The page will be up-

dated with the new star party

coordinator information, as well

as a roll over map showing the

coordinator boundaries, within a

few days. The expenditure of

approximately $25.00, for a

software upgrade on the website,

was approved by the Board.

Old Business:

Pay Phone for TDS: $150.00 was

allocated by the Board to pur-

chase a new coin operated pay

phone at TDS to replace the

current phone.

New Business:

Second Site Report: Jerry

Hilburn reported that he had

contacted the El Centro office of

the Bureau of Land Management

(BLM) about getting BLM for our

second sight. He reported that

the BLM was very interested and

looking forward to working with

us. Jerry and the committee will

be looking at BLM land to find a

suitable sight.

Congressman Filner Visit: Brian

Staples reported that three dates

were given to Filner’s office, no

reply as to when he could visit has

been received.

Nominating Committee: Jerry

Hilburn volunteered to be the

liaison between the Board and the

Nominating Committee. A

committee needs to be formed,

with a chair, so that the nomina-

tions for upcoming elections can

be made for the January elections.

D&O Insurance: The possibility

of the SDAA to obtain Director

and Officer insurance (D&O) was

briefly discussed. Brian Staples

volunteered to find out what the

costs would be before proceeding.

Official Board Notice Policies: It

was discussed and decided that

the SDAA Yahoo Group is not

the official voice of the Board of

Directors and that normal com-

munication mediums, email,

phone, newsletter, regular mail

and meeting attendance, will be

used to relay information to and

from the Board. Scott volun-

teered to put disclaimers on the

Yahoo group to this effect as

soon as possible.

Green Laser Usage at TDS: The

Board heard testimony from

members, reviewed email mes-

sages and listened to statements,

both pro and con on the issue. It

was decided to ban the use of

laser pointers of any color, other

then laser collimators, at TDS.

Scott Baker will update the “Rules

for TDS” and publish them to the

Yahoo Group and SDAA web

page. To help enforce the rules

on the public pads, it was decided

to start a “Public Pad Host”

volunteer position. To help get

volunteers to be a “host”, a

private “Public Pad Host Pad”

will be built, close to the public

pads, where the host for the

evening can set up his scope.

Until the pad is built, a reserved

spot will be indicated on the

South Pad for the host of the

evening, using paint.

The meeting was adjourned at

9:12 PM.

Address Change?Submit your new information to:

[email protected] to ensure you

don’t miss out on SDAA news. If

you ordered a magazine subscrip-

tion through the club, you will still

need to notify the magazine as

well (see each magazine for

change of address instructions).



Hunting Gravitational

Waves: Space

Technology 7

by Patrick L. Barry and Dr.

Tony Phillips

Among the mind-blowing impli-

cations of Einstein’s general

theory of relativity, direct verifica-

tion is still missing for at least

one: gravitational waves. When

massive objects like black holes

move, they ought to create distor-

tions in space-time, and these

distortions should spread and

propagate as waves—waves in the

fabric of space-time itself.

If these waves do exist, they

would offer astronomers a pen-

etrating view of events such as

the birth of the Universe and the

spiraling collisions of giant black

holes. The trick is building a

gravitational wave detector, and

that’s not easy.

Ironically, the gravitational waves

spawned by these exceedingly

violent events are vanishingly

feeble. Gravitational waves exert a

varying tug on objects, but this

tug is so weak that detecting it

requires a device of extraordinary

sensitivity and a way to shield that

device from all other disturbances.

Enter Space Technology 7 (ST-7).

This mission, a partnership

between NASA’s New Millennium

Program and the European Space

Agency (ESA), will place a satel-

lite into a special orbit around the

Sun where the pull of the Earth’s

and Sun’s gravities balance. But

even the minute outside forces

that remain — such as pressure

from sunlight — could interfere

with a search for gravitational

waves.

DRS works by letting two small (4

cm) cubes float freely in the belly

of the satellite. The satellite itself

shields the cubes from outside

forces, so the cubes will naturally

follow an undisturbed orbit. The

satellite can then adjust its own

flight path to match that of the

To make the satellite virtually

disturbance-free, ST-7 will test an

experimental technology that

counteracts outside forces. This

system, called the Disturbance

Reduction System (DRS), is so

exquisitely sensitive that it can

maintain the satellite’s path within

about a nanometer (millionth of a

millimeter) of an undisturbed

elliptical orbit.

cubes using high-precision ion

thrusters. Making the masses

cube-shaped lets DRS sense

deviations in all 6 directions (3

linear, 3 angular).

ST-7 is scheduled to fly in 2008,

but it’s a test mission; it won’t

search for gravitational waves.

That final goal will be achieved by

the NASA/ESA LISA mission(continued page 12)



Tierra del Sol Border Light

Status Reportby Craig Ewing

The lights being placed along the

border near the SDAA's Tierra del

Sol observing site are a concern

to all who use the site. On June

19th, I decided to research it to

find out first hand what is the

situation. That day, Don Spencer

and I drove along the border

fence. Our discoveries were

"enlightening".

We found five "devices", each

with 4 lights attached to the top

of them. (Refer to Boarder Light

A and Boarder Light B.) Each

device was separated by 1/4 mile.

Even though they were located

south-southeast of the SDAA

observing site on June 19th

(Boarder Light C), each device has

wheels and, as such, can be

moved to a different location

relatively quickly. During future

star parties, members may notice

the lights coming from a slightly

different direction.

One interesting thing to note is

that the lights were located along

the top of a ridge that day. If I

remember correctly, I'd heard that

the border patrol said that they

were going to install the lights in a

ravine near the border because

illegal immigrants could more

successfully evade them when

passing through it as opposed to

crossing the border along the

surrounding ridges. The ravine is

approximately 2 miles wide. On

the other hand, I'd heard SDAA

members say that the border

patrol plans on installing enough

lights to cover a 5-mile stretch of

border. If that happens, then the

lights will be able to light up both

the ravine and the surrounding

ridges.

Boarder Light A

Boarder Light B

Boarder Light D

Most of the devices were ar-

ranged so that two of the lights

were pointed down onto the

fence and the other two lights

were pointed out over the fence.

However, the central device had

two lights pointed directly east

and two lights directly west.

(Refer to Boarder Light D.) This

will probably create more light

scattering. Regarding light scatter-

ing, during the night of June 19th,

we noticed increased light pollu-

tion when the moisture in the air

increased. This could be signifi-

cant if and when more lights are

installed.

I hope that this information is

useful to people who are inter-

ested in learning about the border

light situation near Tierra del Sol.

For those of you with Internet

access, I uploaded additional

photographs of our experience in

the "Photos, Border Lights 2"

folder at the SDAA Yahoo! Chat

Group Web page-- http://

groups.yahoo.com/group/

SDAA/.

Boarder Light C

THE BACK PAGE

(Laser Interferometer Space

Antenna), which is expected to

launch in 2011. LISA will use the

DRS technology tested by ST-7 to

create the ultra-stable satellite

platforms it needs to successfully

detect gravitational waves.

If ST-7 and LISA succeed, they’ll

confirm Einstein (again) and

delight astronomers with a new

tool for exploring the Universe.

Read more about ST-7 at http://

nmp.jpl.nasa.gov/st7 . For kids in

a classroom setting, check out the

“Dampen that Drift!” article at

http://spaceplace.nasa.gov/en/

educators/teachers_page2.shtml .

This article was provided by the JetPropulsion Laboratory, CaliforniaInstitute of Technology, under a contractwith the National Aeronautics andSpace Administration.

Space Technology continued from page 10

Classifieds8.0” Meade Starfinder f6 with

equitoral mount. Magellan I,

Celestron 25mm eyepiece, $550.

Douglas Searles

[email protected]

(858) 277-0534


P.O. Box 23215

San Diego, CA 92193-3215

(619) 645-8940VOL XL Issue 10, October 2004

Published Monthly by the San Diego Astronomy AssociationSubscription $8.00/year, Single Issue 75¢

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October 2004 2 - SDAA

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