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Volume 79
Number 1
September 2001
Bad Astronomy
Philip Plait, Ph.D
“The Bad Astronomer”
Saturday, September 1, 2001
Physics Lab, 2nd Floor, Spees Building
• General Meeting – 7:30 pm
• Lecture – 8:00 pm
W
ho is this guy who calls himself "The Bad Astronomer?" Is he really bad? Is he really an astronomer?
First, yes, I am a real live astronomer (when
people ask me what astronomers do, I tell them "They astronom!"). My name is Philip Plait and I work at the physics and
astronomy department at Sonoma State University, a member of
the California State University system. The campus is about 60
kilometers north of San Francisco. I am currently working on a
NASA-sponsored public outreach program for a satellite named
GLAST (Gamma Ray Large Area Space Telescope). I just
started this job in December of 2000 and I am very excited to be
a part of such a great program to educate people about highenergy astronomy. Let me state here that I am not a NASA employee, and anything I say, pretty much ever, is not the official
word from NASA! I always speak for no one but myself.
I received my PhD in astronomy at the University of Virginia
in 1994. While there, I helped teach introductory astronomy
classes and for three years (six semesters) I ran a nighttime lab
where students used binoculars and telescopes to observe the sky. I wrote several of
the exercises for that lab, which helped me
learn how to communicate difficult astronomical techniques to people unfamiliar
with the jargon. UVa also has an observatory located a few kilometers away from
campus, and twice a year would hold Public
Nights so people could come and look
through the telescopes. I usually volunteered
to stay outside the dome and answer questions people had about astronomy. The bug
to teach basic astronomy to the public got a
Predecessor to Chabot’s Mark IX Universarium? No! It’s the
navigator’s station aboard the United Planet Cruiser C-57D in
the classic 1956 sci-fi movie, Forbidden Planet, with more bad
astronomy than you can shake a stick at. Still, it was a great film,
nonetheless.
hold of me during those nights.
Before that, I was (and still am) an avid amateur. I had a
10" reflecting telescope for over 20 years (I bought it when
I was 13 years old), and now here at Sonoma State I have
access to a 14" and another 10", so I am still very much active in hands-on astronomy. !
DINNER WITH THE
SPEAKER
5:30 PM
Saturday, Sept 1, 2001
PEARL OF SIAM
RESTAURANT
5498 College Ave.
Oakland
(510) 420-8600
Please call Betty Neall at
(510) 533-2394 by Friday, August 31, 2001 to
confirm your place
Inside This Issue:
Cygnus the Swan
Saturn Season
Chabot News
Membership Renew
Editor’s Views
This Month’s Photos
Survey on Meeting
Format
2
3
3
4
5
5
5
Cygnus, the Swan
By Ellis Myers
T
he finest star fields to be found in the northern sky
are those of Cygnus, although at lower latitudes
Scorpius and Sagittarius are more than equal in
splendor. Wonderful views are here for binoculars;
and for small telescopes worthy targets are nearly endless.
Premiere among these objects is Albireo, Beta Cygni, at the
bill of the swan, or the base of the Northern Cross. It’s probably the prettiest of all the double stars, for it is a magnificent
blue and gold. Alpha Cygni, the brightest star in the constellation—18th brightest of all stars—and the most distant of firstmagnitude stars, is Deneb; a luminous white supergiant.
Of deep-sky objects, the North America Nebula is the best
known. The glow of the nebulosity, larger than the Moon, can
be seen using large-aperture binoculars. M29 and M39 are
both open clusters of stars. M39 is both the larger and brighter.
It is said that Aristotle recognized it as early as 325 bc.
With a 6-inch or larger telescope, you may be fortunate to
enjoy the Veil Nebula, which is part of the visible aftermath of
a supernova that exploded sometime in the far distant past. In
the recent past, other novae have appeared in the constellation.
One happened in August 1975 (well, not really — it happened
about 3700 bc, but was first observed in 1975), when a 21st
magnitude star increased its luminosity 40 million times to an
apparent magnitude of 1.8; nearly as bright as nearby Deneb.
Within two weeks Nova Cygni 1975 was no longer visible to
the naked eye.
Many times more massive than the Sun, P Cygni's nuclear
furnace burns much hotter—so hot that the star can’t hold itself together. Radiation pressure pushes the gas in its outer layers into space. As the expelled shell of gas gets thicker or thinner, the star’s brightness appears to change. For over a century,
[2]
until 1715, the star flared up and cooled down with a irregular
period of about three years, but since then it has been quiet at
about magnitude five.
Double star 16 Cygni is one of special interest. As one of
the nearest stars to the Solar System, this was among the first
systems to be searched for possible extra-solar planets. And in
July 1997, Paul Butler and Geoff Marcy, at San Francisco
State University, along with astronomers from the University
of Texas, announced the co-discovery of a planet, somewhat
larger than Jupiter, in orbit around one of the Sun-like pair. To
date more than 58 planets have been found around stars other
than our Sun.
Assyrians, Arabs, and Greeks described this grouping of
stars as some form of bird, but the name we use today comes
fom Roman mythology. Two major stories are connected,
along with lesser stories. In one of Jupiter's many lustful liaisons, he changed his form into that of a swan in order to seduce Leda, wife of King Tyndareus of Sparta. From this union
was born the twins Castor and Pollux, Castor the mortal son of
the king, Pollux the divine son of Jupiter. Leda was also the
mother of Helen of Troy.
Phaethon was the son of Apollo, god of the Sun, and the
nymph Clymene. When one of his friends challenged him to
prove he was the son of a god, Phaethon asked his father to be
allowed to drive the chariot of the Sun for one day across the
sky. But as he spurred the mighty steeds to the noon heights,
Phaethon became frightened and lost control. The chariot
plunged toward the claws of Scorpius. To prevent an impending catastrophe, Jupiter threw a thunderbolt that knocked
Phaethon from the chariot and he fell into the river Po. Apollo
was able to rescue the raging horses in mid-flight and lead
them to their western stables at twilight.
Cycnus was Phaethon's beloved brother and he was nearly
overcome with grief over his brother's death. He vowed to give
Phaethon a proper burial, and he repeatedly dove into the waters of the Po to find the charred body. The gods of Mount
Olympus were touched by this
devotion while they were
amused by the likeness of
Cycnus to a swan diving for
food. They decided to reward
the brotherly love by placing
him among the stars.
Eight stars of this constellation form an asterism that is
popularly known as the Northern Cross. The base of the
cross is Albireo, the beak of
the swan, while the top of the
cross is Deneb, the tail. Deneb
is also part of another asterism,
the Summer Triangle, joined
by Vega in Lyra and Altair in
Aquila.!
North American Nebula, NGC
7000 Photo by Conrad Jung
exceed resolution limits. We all experience this when
flying at about 30,000 feet and can see a road extending far
into the distance well beyond our eyes’ resolving ability.
An interesting measure of Saturn’s progress toward and
Photo and article by Jim Scala
then past opposition is the slowly changing shadow of the
planet on the rings, which are easily seen just to the left in
rguably, the amateur’s favorite showpiece,
Saturn, will make excellent observing during the image. This shadow will disappear at opposition and
then grow again on the opposite side.
the 2001-2002 opposition that occurs on
rd
In my 228-mm refractor, others and I have seen the
December 3 . At 20º 18' declination, where
Enke
division (between Cassini’s division and the outer
the air is clear, darkest, and above the trees, the opposition
edge) visually and this opwill dominate the observing
position is an excellent
season. Even better, the rings
chance to capture it with a
which are tilted 26º are
CCD that will once again
almost at their widest of this
seemingly defy resolution
current 13.5 year ring cycle.
laws. A few amateurs who
Hence, this is a superb
specialize in high-resolution
opportunity to study Saturn’s
CCD imaging have captured
rings at their best, and to test
Enke’s division. I will be
your observing skills and
trying hard to capture it this
understand telescope limits.
observing season. With the
The above CCD image taken
th
rings so wide, it’s possible
on August 8 at 0500 PDT
th
to see Saturn’s disk through
Saturn on August 8 at 0500 (1200 UT) as seen through an
(228-mm APO refractor)
the inner Crepe ring. This
inverting telescope. A CCD image acquired with a Santa
illustrates a few of the
Barbara Instrument Corporation ST-10E equipped with a CFW-8 elusive ring is seen in the
possibilities available with
amateur telescopes. Saturn’s color filter wheel. The telescope is a 228-mm F/9 Apochromatic image as the vague inner
Refractor housed in my backyard observatory in Lafayette CA.
beginning of the rings themdisk at 17.52" and rings at
selves. In overly enlarged
39.74" will increase to 20.6"
versions
of
the
above
image,
a
hint
of the disk seems to be
and 46.6", respectively, by December 3rd. Most noticeable
visible.
on the rings is the dark Cassini division (almost empty
On September 10th at 0456, the Moon will occult Saturn
space), which was 0.62" wide, even though it seems larger.
in a dark sky. Sky and Telescope and other publications
Test to see how small a telescope allows you to see this
division. Although Cassini’s division is small at 0.65", on have excellent detailed coverage of this event. With the
rings at 26º, this occultation will be the most spectacular in
average, it is an extended object (extended dark space),
many decades. !
making it possible for small telescopes to seemingly
The Saturn Season Begins:
2001-2002 Will Be Spectacular
A
News From Chabot
By Denni Medlock
Two new planetarium shows, Cosmic Catastrophes and
Other Worlds! Other Beings start August 25. A new
movie, The Living Sea, starts in the Tien MegaDome
theatre on Labor Day weekend, Saturday, Sept 1-3 – check
with Chabot (www.chabotspace.org or 510 336-7491) for
exact showtimes. There will be a speaker from SETI for the
premier showing of OWOB at 8:30pm.
A low-math Astronomy class for beginners is being
offered Tuesday evenings, starting October 2 - November 6
from 7:30 - 9:30pm at Chabot. Guest instructors will lead
students through the fundamentals of modern astronomy,
with time in the planetarium and observatories. Cost is $55
for CSSC members, $65 for non-members. Class size is
limited so early reservations are advised. Reservations may
be made through Chabot, through TicketWeb, or by mailing
a check made out to: Chabot Space and Science Center, to
Chabot Space and Science Center, c/o D. Medlock, 10000
Skyline Blvd. Blvd. Oakland, CA 94619.
The Chabot Vacuum Solar Telescope is currently in
Chabot’s workshop at Alameda Point. Recently the upper
head assembly's exterior was sandblasted and repainted in
preparation of installation of the optics located there. Joe
Waidl has completed the electronics and optical path
design work, and was part of the Chabot team that traveled
to the Canary Islands to extract the telescope from the
Swedish Royal Observatory.
The original light path of the telescope is too long to fit
into Chabot's facility so it has to be "squeezed" down for
display in the exhibit area, located in Astronomy Hall. Projected time of completion: late Fall, 2001. The Project
Team consists of Kevin Medlock, Joe Waidl, David Sisson and Frank Panza, while Ben Burress is team leader of
the exhibit side of the solar telescope. Construction of the
exhibit wall was done by EAS' Ken Swagerty. !
[3]
MEMBERSHIP RENEWAL FORM
Eastbay Astronomical Society
2002
(Must be completed and turned in no later than September 15th to ensure
uninterrupted delivery of the newsletter)
" New " Renewal
NAME: (please print________________________________________________________________
ADDRESS:_______________________________________________________________________
CITY, STATE ZIP__________________________________________________________________
DAY PHONE:_(____)_______________________EVE PHONE:_(____)_______________________
EMAIL ADDRESS: (please print)______________________________________________________
MEMBERSHIP CATEGORIES:
Optional discounted 12-month magazine subscriptions:
" Regular $24
" Family $36
" Contributing $40
" Sustaining $60 or more
" Sky & Telescope $29.95
" Astronomy $29.00
Optional, tax deductible donation(s) to any of the projects
of the Eastbay Astronomical Society:
"Video Projector "Burns Library
"Other:________________________ $________________
Total Enclosed: ________________
Please mail this form and your check or money order payable to:
Eastbay Astronomical Society
19047 Robinson Road
Sonoma, CA 95476-5517
For further information, please contact Treasurer and Membership Chairman Don Stone at
(707) 938-1667, [email protected], or write him at the Sonoma address, above.
As a cost savings to us, instead of getting a mailed hardcopy newsletter, would you prefer to be notified via email that:
" The .pdf version of the newsletter is availble for download from our website, or
" The newsletter is available to be viewed on the club’s website (http://www.eastbayastro.org/)
(Note: .pdf or web accessed newsletters are delivered faster, are in full color and help conserve paper, too!)
And,
" Are you interested in volunteering your time/equipment for public stargazing at Chabot?
" Other volunteer work for Chabot and/or the Eastbay Astronomical Society?
THANK YOU!
[4]
No doubt about it:
theirs is definitely
bigger than ours. The
36” Warner Swazey
refractor at Lick Observatory makes Rachel look like a
matchstick. Rachel is
much prettier and
more accessible,
though.
Editor’s News ‘n Views
By Don Saito
A
s always, lots of things happening or about to
happen! A real convergence occurred this month
with Barcroft, the Davis Star Show, Bort
Meadows, and the Chinatown StreetFest. They’re
all happening right now, so as I write this, I don’t have any
details on them at all – I’m hoping y’all will help me out when
you come back from some or all of these events with your own
pictures and stories (wink-wink, nod-nod knowwhatImean,
knowwhatImean?) One thing that happened that I can write
about is EAS’ recent television exposure on KQED Channel 9;
a group of us, Richard Campbell, Phil Crabbe, Anne and
Frank Creese, Debbie Dyke, Mike Hanley, Howard
Mangrum, Alan Roche, Dave Rodrigues and myself did
volunteer phone duty for one of the public television station’s
pledge drives.It was fun! First, they fed (should I say
‘stuffed?‘) us with gormet food from a great caterer. Then they
briefed us on the forms and procedures. We were nervous at
first, but after the calls started coming in, it became quite easy,
and since we had an inside man on the camera (take a bow,
Harry Betancourt!), we got the best seating in the house,
plenty of coverage, and even intimate tours of the different
production facilities and sets from Harry; very interesting
stuff! Anyone interested in doing this in the future, let me
know – there’s nothing like repeated exposure to up that brand
name recognition with the public.
Chabot will be sponsoring a Leonid Observing Session
dusk to dawn Saturday, Nov. 17- Sunday, Nov 18 at Briones
Regional park in Lafayette. Tickets to the event will be available at Chabot and through TicketWeb starting in October. $5
gets entrance to a dark sky site, a hot beverage and snacks,
roving astronomers to answer questions and telescopes to view
other objects through. (Thanks, Denni!)
I have a confession to make: I defected to another observatory, twice, this month. Yes, it’s true: I went up to Lick Observatory and commingled with the staff, astronomers, and volunteers up there. Once to attend their “Music of the Spheres”
program (combination of music, lecture, and viewing), and
again, for their straight lecture/viewing program. It’s a little
tricky getting tickets; you have to know what time of year to
keep an eye on their website to know precisely when to call
them for reservations. And then, they use a lottery system, so
you still might not get in. Well worth the effort, though – it’s a
remarkable facility with limited public access (only during the
summer). It’s too late to even think of trying this year. Go to
their website or give them a call to find out how to get tickets
for next year.
And here’s this month’s collection of pictures of various
localized phenomenon involving club members and/or Chabot.
Enjoy, enjoy! !
PS: Don’t forget – there’s an early morning occultation of
Saturn by the moon on September 10th at 4:56am.
Dave Rodrigues, Alan Roche Don Saito, Debbie Dyke, Howard
Mangrum ready for action in KQED’s broadcast studio!
Debbie Dyke inspects
Leah’s lens before Ken Swagerty puts on the freshly
made brass dewcap.
Survey Time: How did you like having the
lecture portion of the July meeting in the Tien
MegaDome theatre?
We started at 5:30pm and went until a bit after 7:00pm. The
only question is: How did you like it? Let us know what you
thought of the new meeting format. If we get a largely positive
feedback on it, we’ll change it, permanently.
Call, email, or write your response to the Editor at:
Phone: (510) 482-2913 (leave a short message stating only
your name, phone number, and your vote: “liked it,” or “didn’t
like it.”
Email: [email protected]
SnailMail: 3514 Randolph Ave, Oakland, CA 94602-1228
[5]
Eastbay
Astronomical
Society
At Chabot Space & Science Center
10000 Skyline Boulevard $ Oakland, CA 94619
September 2001
RETURN SERVICE REQUESTED
FUTURE CONJUNCTIONS
Sep
1 7:30pm EAS Lecture/Meeting, Chabot*
13 7:30pm EAS Board Meeting, Chabot
Oct
13 7:30pm EAS Lecture/ Meeting, Chabot
6 ENCHILADA Meeting, Chabot
11 7:30pm EAS Board Meeting, Chabot
*there was a typo in last month’s listing – this is the correct date
Eastbay Astronomical Society
President:
Carter Roberts
Vice President:
Treasurer, Membership:
Phil Crabbe II
Don Stone
(510) 524-2146
[email protected]
(510) 655-4772
(707) 938-1667
[email protected]
Articles and photos for The Refractor are encouraged. Deadline for the October
issue is September 15, 2001. Items may be submitted by mail to the editor, Don
Saito, 3514 Randolph Avenue, Oakland, CA 94602-1228. Internet email address: [email protected]. Day: (510) 587-6052 Eve: (510) 482-2913.
Join the Eastbay Astronomical Society
! Regular, $24/year
! Family, $36/year
! Contributing, $40/year ! Sustaining, $60/year or more
Contact: Don Stone, EAS Membership Registrar
Telephone: (707) 938-1667 Email: [email protected]
Mail: 19047 Robinson Road, Sonoma, CA 95476-5517