
ASTRONOMY CLUB OF TULSA
OBSERVER
November
2001
http://AstroTulsa.com
ACT, Inc. has been meeting continuously
since 1937 and was incorporated in 1986. It is a nonprofit; tax
deductible organization dedicated to promoting, to the public, the art
of viewing and the scientific aspect of astronomy.
What
The Astronomy Club of Tulsa Club
Annual Dinner
Meeting
When
Thursday, November 8, 2001 at 6:00 PM
Where
Furr's Cafeteria E. 41st St and
Garnett in the shopping center East of REASOR's
When you arrive, go through the serving line and
meet us in the reserved conference room.
Notes from the President
John Land
The annual dinner meeting
is one of the most enjoyable times of the year.
Astronomy Club members and their families get together for a meal and
fellowship. Bring the wife and kids. The procedure is to go through the
line, make your selections, bring them to our meeting room. Then go pay your
ticket. If you just want to come for the meeting come about 6:30 and just
visit awhile. The cafeteria closes at 8:00 PM so we must be gone by 7:45 PM
We will eat, visit, elect
officers and talk about our hopes of viewing
the long awaited Leonid Meteor Storm Nov 17-18 and the Dec 14 partial Solar
Eclipse.
Leonid Meteor Storm possible
2000 per hour for a short burst.
The scientists who do the
mathematical modeling for this event have been
pretty accurate the last two years. Many of you remember the grand display
of bright meteors from the 97 and 98 showers. Last years shower was
disappointing. This year one to the two expected peaks occurs at 2:00 AM on
Sunday morning November 18 just as the radiant in Leo is rising. IF the
predictions hold true we could be in for a grand show. We will be having an
all night observing session at the Mounds Observatory. The moon is a thin
waxing crescent and sets early in the evening. Club members and small groups
of guests they bring with them are welcome. WE ARE NOT OPENING THIS UP TO
THE GENERAL PUBLIC ! ! We had a near disaster 3 years ago when a local TV
station put us on their website and over 400 people showed up!!
Charity Public Star Party at Chandler Park
Sat Nov 10
6:00 PM to 10:00
PM
Rain date Sat Nov 17th
To get there take Hwy 75 to
21st Street, take 21st St. west for about 2.5
miles, you will see a huge "CHANDLER PARK" sign on the side of the
hill going up to the park on your left.
Sponsored by Outback Guides,
American Red Cross, Tulsa County Parks, and
Chandler Park & Educational Council. It is being advertised on Tulsa
radio & TV stations to benefit by donation the people in the World Trade
Center disaster that did not have any insurance or any other means to
support their families. Originally, it was to benefit NY Police &
Firemen, but they have more than enough compensation.
Please put this info
in the Tulsa Astronomy Club newsletter. Thanks, Rick Harris Oklahoma City
Astronomy club
Note: The OKC Club
does some public star parties through the Department
of Tourism at some State Parks. One of their past Presidents, Steve Atkins,
works for the Tourism Department. Anyway that's how this event came into
being. This should give us some major exposure and also help a good cause. I
realize the rain date is the Leonid shower but the public event will be over
long before the expected peak of the shower. We did not schedule this.
We need to be SET up
ready to Go no later than 5:15 PM Cloudy or not
people will show up. Those of you with solar filters may want to bring them
before sunset. Please contact Gerry Andries Phone or
< Gerry Andries e-mail > to
confirm your commitment to help
Dec. 7th -at TU campus - Space Artist - Robert Daniels
We have invited Robert
Daniels, of Silverwings Studio in Oklahoma City to
come demonstrate his Art of the Universe collection. At the meeting he will
let us observe as he completes an actual painting envisioning an astronomy
vista. Mr Daniels has done several art demonstrations for schools in the
Oklahoma City area. We would like to invite artists, young or old, as well
as space enthusiast to come enjoy this experience with us. Daniels will also
have some of his collection available for sale. Prints sell from $20 to $40
and Original paintings start at about $120. You may find some great ideas
for those special Christmas gifts for the astronomer. I had the pleasure of
watching in amazement as he created his personal visions of the universe on
canvas. You won't want to miss this one!
Win an Astronomy painting.
Robert has graciously offered to donate the
painting he does to the club. We will give out drawing tickets for donations
of $2.00 each. The winning ticket will take home the painting created for us
that evening!
Officer Candidates:
President: Denny Mishler
- Denny has been active in our Tulsa club for
about four years. Although he is new to Tulsa, Denny is not new to
astronomy. He has been actively pursuing astronomy since the age of 10 when
he received his first telescope. He continued to do astronomy in high school
and college. An Engineering graduate, Denny has lived in several areas of
the country. He was a member of the Baltimore Astronomical Society (the 3rd
in the nation) where he helped organize their 100th year celebration. (By
the way if our history is correct the Tulsa club will celebrate its 75th
anniversary during 2002 !) Denny has also served as president of another
club in Maryland. Since coming to Tulsa, Denny has helped to welcome new
members and served as our vice president. Denny is a Lowe's Lumber store
regional representative and has an opportunity to make contacts with other
astronomy clubs in this region.
Vice President: Teresa Kincannon
- Teresa has been a member for several
years and brings a lot of enthusiasm to the club. She and her son Jason got
"into" astronomy with both feet going out to see the comet
fragments from Shoemaker-Levy 9 hitting Jupiter. They went interested in
astronomy for some time before that and went to the library to keep up
with events, which fortunately brought her to
us. Teresa is a middle school science teacher in Tulsa and brings a lot to
energy from her "kids" to us. She has been our secretary for
several years.
Secretary: Aaron Coyner
- Aaron has been an active member of our club for
about four years. As a high school student he organized the Astronomy Club
at Broken Arrow High and started participating in activities with our Tulsa
Club. As our club representative at TU he helps make sure we have our
meeting room and equipment each month. His interest in astronomy stretches
clear back to Comet Halley! in 1986. Even in those early years astronomy was
his passion. Aaron is a Physic student at TU and currently working of a
research project for a Space Shuttle "Get-Away Special" He was on
our board last year and designed the nice Polo Style Astronomy Club Shirts
and the excellent PR pamphlet for our club.
Treasurer: Nick Pottorf
Assistant Treasurer - John Land
Nick Pottorf has
been active in the Tulsa Club since the early 60's. Nick
is the number one reason the Tulsa Club has been so successful and
financially stable over the years. Nick has HAND-MADE many excellent
telescopes, mirrors, and eyepieces over the years. He is a master craftsman
of metal and glass and can put even the commercial manufacturers to shame.
Anyone who has been in the club for a few years has probably benefited from
Nick's advice, encouragement and gentle demeanor over the past four decades.
Trained in Engineering, Nick became a Patent Lawyer for Standard Oil, which
later became AMMACO and now BP AMMACO.
John Land - I will
be assisting Nick with the treasurer duties and
"learning the ropes" of all the tiny details it takes to keep the
club memberships, subscriptions and accounts going smoothly. Nick was the
first person I contacted about the astronomy club when I joined in 1977. I
drove up from Okemah 70 miles each month just to get in on all the exciting
things the club members could teach me. I had always been a Space Age
enthusiast. As a child, my mother and I used to go out and watch THE
(singular) Echo I satellite go over at night. About 2 AM in June of 1977 I
"discovered" M-11 with a small 60mm refractor and Tom McDonough
(then a high school student) introduced me to the fact that there were 109
more of these to be discovered. I was hopelessly addicted to starlight. I am
a teacher at Broken Arrow SR High and have had the privilege of teaching
astronomy and other science courses there for more than 20 years. I have
served as Observing chairman, President, Mid- States Chairman and board
member at various times over the years. I would like to thank all of you for
your support over the last two years I served as president as we tried to
get the club back on a firm foundation. I think this new group of officers
will bring some fresh views and enthusiasm to the club.
Board Representatives.
Gerry Andries, Steve
Chapman and Hugh Selman
Gerry has been our
Observatory Chairman for several years and does an
excellent job of scheduling all the groups and events that visit the
observatory. He keeps the observatory grounds mowed and cleared of evening
deposits from the local Bovine population. He is the virtuoso of the 16-inch
telescope. No one else gave get the beast to lock onto and track the stars
quite like Gerry can. He is an enthusiast of flying and especially
Ultralight aircraft.
Steve has been
active in the club for many years. A regular at observing
nights and after hour's discussions at I-Hop pancake house, Steve is always
willing to drive in from the Verdigris River Valley to help with observing
groups and club events. His daughter Susan has also been a regular bringing
her friends to search for the hidden treasurers in the dark skies. Steve
works on the navigation systems for a Tulsa based Aeronautics Company.
Hugh is a retired
electrical engineer who became interested in astronomy
during the Hale-Bopp era. He spent many hours in the summer of 2000 helping
make repairs to the observatory. He and his wife have become "starlight
groupies" making the long trek to the Texas Star Party and Okie-Tex
Star parties in their motor home. Hugh says he just wants to learn as much
as possible about astronomy.
Club Business:
This is the time for our
annual reports of club business.
TIME TO PAY OUR DUES
FOR 2002 - $25
You can also renew your
subscription for Astronomy $29 and Sky &
Telescope $30
Also time to order Canadian
Observing Handbooks $15 -
Gerry is taking
orders through Nov 8 for the
Year in Space Weekly desk
calendars. $9.00 for 52 pages of space shots and room to schedule all your
events. This year you must pay in advance. Nick or Gerry
will have details.
NICK POTTORF is offering his 40+ year collection of Sky and Telescopes to
interested club members. They will be bundled by year and you may purchase a
whole year's worth by making a donation to the club. Think of all those
wonderful discovers you read about in the history books. This is your chance
to read about them and "SEE" them "LIVE" through the
eyes of those who first discovered them. We have several left at $3.00 per
year. Many of them are neatly boxed in sets.
NEWSLETTER ARTICLES - If you want to write up a project you've done, a
special observing interest, science topic - we'd love to see them included.
Send us a few paragraphs or up to a page. If possible we'd like to have it
sent e-mail. Be sure you've done your research well and grammar checking
before you send it in. We would also like to have a few paragraphs relating
a personal observing experience or a favorite sky lore story. If anyone
would like to take on a Monthly article I'd like to see an Observing
Challenges article featuring a constellation or type of objects and say a
top ten targets for u to find this month. I've seen these in some other club
letters and they make up a contest to see who can find them.
CLUB DOOR PRIZES
We have found that a door prize or two helps keep our audience around
until the end of the program. If you have some good quality but extra
astronomy pictures posters - eyepieces or other astronomy products you'd
like to donate they would be greatly appreciated.
OBSERVATORY CARE & REPAIR
Gerry Andries can use help immediately with lawn care and weed control.
Due to the extreme heat this summer our repair projects are still undone. We
will be looking for help later this fall. If you have time and equipment
contact Gerry.
VOLUNTEERS NEEDED:
The following is the current schedule of star parties and public groups.
Tentatively scheduled dates are bracketed with question marks. All events
are at the RMCC unless noted otherwise: Contact Gerry Andries 369 3320
EVENTS AT RMCC OBSERVATORY
NOV
11-02-01 Fri 05:00 TU Astronomy and
Astrophysics w/ Aaron Coyner (40)
11-03-01 Sat 05:00 Backup for 11/02
1
1-17-01 Sat 05:00 PM to Dawn Sunday 18th Leonid Meteor Storm 2000 Per hour
???? Peak somewhere for 2:00 to 04:00 AM Leo rises around 2:00 AM
?11-19-01
Mon 04:45 Jenks HS Sci Fi Literature Class (30) ?
?11-20-01 Tue 05:00 Backup
for 11/19 ?
EVENTS AWAY FROM
NOV
11-08-01 Thu 6:00 PM Holiday Dinner Meet (Furrs at
41st & Garnett)
11-10-01 Sat 6:00 PM to 10:00 PM - will have TV and
Radio spots Charity Benefit Star Party at Chandler Park
DEC
12-07-01 Fri
07:30 Regular Meeting (at Keplinger Hall)
12-14-01 Fri 03:00 Partial Solar
Eclipse & Club Star Party and Geminid Meteor Shower
2002 Calendar of events
STAR PARTY at RMCC |
MEETINGS at TU |
|
|
Jan 11 |
Jan 25 |
Feb 08 |
Feb 22 |
Mar 08 |
Mar 22 |
Apr 12 |
Apr 26 |
May 10 |
May 24 |
Subject: K.C.'s GANG INVADES OKIE-TEX
Led by K.C. Lobrecht who
arrived at the beginning of the week long
Astrofest known as "Okie-Tex" (located at the end of Oklahoma's
Panhandle) a rather large contingent of ACT members and friends converged on
the lonely outpost of Kenton, OK for a week of excellent weather and
viewing. Chris Brown who teaches Astronomy at TCC brought his entourage of
students and fans swelling the Tulsa contingent to perhaps 30 people. Hugh
and Peggy Selman brought their beautiful motor home. Campers included Gary
Buckmaster, Blake Chamlin, Rod and Jenny Gallager, John Land, James Liley,
Howard Minor, Denny and Barb Mishler, Dean Salman, and Jay Tiner.
Okie-Tex may be the best
Star Party I've attended. Stellafane in
Springfield, Vermont is the grand daddy of Star parties and attracts 2000
fans. But it lasts only 2 nights and the skies are not comparable to the
black skies of Oklahoma's Black Mesa territory. The Texas Star party is a
good one but the skies aren't quite as good and it can get hot and dusty
when it is held in May. Located 430 miles west of Tulsa with all the driving
in Oklahoma, Okie-Tex gets my vote and if you stay for the final night you
are quite likely to win a nice door prize too!
Denny Mishler, Club vice President
DAVID'S ASTRO CORNER
"A STORM IS BREWING!"
by David Stine
Where will you be on
November 18, 2001 in the early morning hours? If you
say probably home asleep, that is the wrong answer and you could be very
sorry. So what happens on that morning you say? Possibly the greatest meteor
storm that our lifetime has seen with the exception of 1966. If the
forecasters are correct like they have been the past two years we may
witness a meteor almost every second during the peak hour. More than a
person could even try to see. They would be coming from all over the sky.
Lets take a look at the storm forecast from several well known meteor
experts, but first of all for you new to astronomy, let me brief you on this
particular occurrence.
Each year at about the
same time in November we have what is called, a
meteor shower, or as some people call them falling stars. Meteors are not
stars and it's a good thing they aren't or we would be in trouble. What you
see as a streak across the heavens is merely a very small grain from the
debris given off from a comets past passage. This particular comet is Comet
55P/Tempel-Tuttle. This debris remains in roughly the same path that the
comet takes around the sun. Now when this debris is past through by Earth,
we have a meteor shower. This shower seems to have meteors streaking out of
the constellation Leo and that is where its name comes from, Leonid Meteor
Shower. Most of the time the shower is very weak, maybe 10 meteors an hour
at its best, but then there are times every 30-35 years that the shower
comes alive and it is called a meteor storm. We are now in that time period.
The last two years have produced outstanding storms in other parts of the
world. This year and 2002 it's our turn. Why such outstanding storms every
third of a century? The answer lies in the return of the comet. Comet Tempel-Tuttle
reached perihelion in February 1998. The thickest areas of its debris have
since been flowing through the same area that Earth crosses each November
17-18. Astronomers have recently been able to calculate the locations in
space of individual dust trails. According to these individuals we are in
for two more good years of storms before the Leonids go into hibernation.
Who are these forecasters and what are they saying about this year?
Robert McNaught and
David Asher predicted the 1999 storm to within 6
minutes. Asher also was the one who determined the cause of the fireball
year in 1998 that many of us witnessed at the observatory. These particles
came from the 1333 passage and were pulled close together by several passes
near the planet Jupiter creating a concentration of particles in the broader
stream. So what does McNaught and Asher predict for us this year? Asher is
predicting a peak time of 10:01UT November 18 which would be 4:01a.m.CST.
Leo would be very high in the East for an ideal shower. So what is he
predicting for numbers? 2,000-2,500 an hour during this peak time. The dust
particles we will be seeing are from the comets 1766 return, plus particles
from the 1799 and 1833 passage. If this were to happen you would be seeing a
meteor just about every second. Now that would be awesome. They also predict
another peak at 17:31UT the 1699 passage, then another one at 18:19UT the
1866 trail. Of course it will be daylight in Tulsa for this one and we won't
be able to see it. Asher predicts 9,000/hr for the first one and 15,000/hr
for the next one. Being so close together will make for an enormous storm
for people in Eastern Asia and Australia.
Our other experts Esko
Lyytinen and Tom Van Flandern also predict between
2,000 and 2, 500 meteors but 30 minutes later at 10:28UT. Both models are
leading to a major storm for observers in Tulsa and most of North America.
But don't bet on it! We still are not at the stage where we can predict how
broad the stream is or how stretched out it is. But it looks like we could
be seeing more meteors than we have ever seen in our short time on Earth.
The only thing that could prevent us from seeing this spectacle is the
weather.
Come join us at the
observatory the night of November 17 and the morning
of the 18th to watch this awesome display in the heavens. Plan on an all
night session. Again nothing is certain, but the odds are heavily in our
favor for a storm.
What about 2002? Well
if you can believe it, we get the peak again next
year and oh what a peak. Predictions are for 30,000/hr at 10:36UT. North
America will be the only place on earth to view this show. The only problem
is the moon will almost be full, but 30,000 meteors under a full moon, I
don't think that will hamper our view. Who can see that many meteors at one
time? That's appx. 8 meteors a second. You would have to have eyes in the
back of your head.
The next two years are
going to be awesome and we are lucky to be right
in the ballpark for the event. It all starts in a few days. Don't miss it.
COMET UPDATE; Comet C/2000
WM1 (Linear) continues to slowly brighten. By
the night of the Leonid Shower it should be around Mg. 6.6 traveling through
Perseus near the star Algol. If there is room in the newsletter there will
be a plat of the comets path through November 20th. It will be high overhead
on the night of the Leonid Storm, a preview bonus for everyone before the
fireworks start.
That's it from my corner
this month; hope to see everyone at the
observatory Nov. 17-18 for possibly the greatest meteor shower we have seen
yet.
**********************************
NAMN Notes: November 2001 **********************************
Introduction:
NAMN Notes is a
monthly newsletter produced by the North American Meteor Network, and is
available both via email, and on the NAMN website at:
http://www.namnmeteors.org
1. Leonids - Event of
the Year!...
What is this shower?
The Leonids are a sight of a lifetime when they storm, and they are
predicted to storm in large numbers this year. These meteors are debris from
Comet 55P/Tempel-Tuttle.
i) The Parent Comet...
The comet was
discovered on December 19th, 1865 by Ernst Wilhelm Liebrecht Tempel in
Marseilles, France. Tempel was born in 1821 in Nieder-Kunersdorf, in Saxony.
He trained as a lithographer, and took up astronomy as a side interest. When
he moved to Venice, he purchased a 4 inch refractor, and started looking for
comets from a balcony of a Venetian palace. He found his first in 1859, also
the year in which he became the first observer to note the nebula around the
star Merope in the Pleiades. In 1860, he moved to Marseilles, France,
obtained employment at the observatory, and went on to discover 8 more
comets, including the famous Tempel-Tuttle as we now know it. In 1871 he
moved to Milan, Italy, taking a job as an assistant to Schiaparelli at the
Brera Observatory. He discovered 3 more comets at Milan. In late 1874 he
moved to Florence and the Arcetri Observatory, and using larger telescopes,
found 1 more comet. In all, he was the first discoverer of 13 comets. Tempel
died in 1889, and was buried near the tomb of Donati, whose name is also
famous for comets.
Comet Tempel-Tuttle
was also discovered by Horace Parnell Tuttle of Harvard College Observatory,
Cambridge, Massachusetts, USA on January 6th, 1866. Tuttle was an assistant
astronomer at the Harvard College Observatory. He discovered his first comet
in 1857, which turned out to be periodic Comet Brorsen. In 1858 he made a
first discovery of Comet 1858 I, now called periodic Comet Tuttle. He went
on to a total of 4 comet discoveries, and 9 co-discoveries. The most famous
of these comets are 1862 III Swift-Tuttle, the parent of the Perseid
meteors, and 1866 I Tempel-Tuttle, the parent of the Leonid meteors. In
1862, Tuttle left Harvard, served in the infantry in the American Civil War,
then transferred to the navy. He served on the U.S.S. Catskill, an iron-clad
ship engaged in the blockade of Charleston Harbor in South Carolina. By day
he acted as paymaster... and by night he made observations of comets! After
the navy, he worked with the U.S. Geological Survey, and helped define the
boundary line between Wyoming and the Dakotas. Tuttle died in 1923 and was
buried in an unmarked grave at the Oakwood Cemetery in Falls Church,
Virginia.
ii) The Early Leonid
Observations...
There are many old
descriptions of the Leonid meteors, as they have been observed for over 1000
years, long before their cometary origin was known. In his book 'The Story
of the Heavens' published in 1886, Sir Robert Ball wrote:
"On the 12th of
October, in the year 902, occurred the death of a Moorish king, and in
connection with this event an old chronicler relates how 'that night there
were seen, as it were lances, an infinite number of stars, which scattered
themselves like rain to right and left, and that year was called the Year of
the Stars.'"
We now know, due to
calendar allowances, that this referred to the Leonids, and is one of the
first recorded instances of the shower.
November of 1833
sparked the current birth of meteor astronomy as we know it. A Leonid storm
was widely observed in North America. Observations of the event led to
Denison Olmsted's theorizing that the meteors had originated from a cloud of
particles in space - and a specific radiant point for the meteors. Old
records were looked at, and von Humboldt's observations of 1799 from South
America discovered. The possibility of annual activity in November was
realized. In 1837, Heinrich Olbers reported a period for the Leonids of
about 33 or so years.
Hubert A. Newton
examined many old records, and identified many years of Leonid activity. He
predicted the next return 33 years later, in 1866, and a meteor storm
occurred. Sir Robert Ball wrote:
"Such was the
occurrence which astonished the world on the night between November 13th and
14th, 1866. The meteors were distinguished not only by their enormous
multitude, but by their intrinsic magnificence. I shall never forget that
night... I was engaged in my usual duty at that time of observing nebulae
with Lord Rosse's great reflecting telescope... The late Earl of Rosse...
joined me at the telescope, and, after a brief interval, we decided to cease
our observations of the nebulae and ascend to the top of the wall of the
great telescope... There, for the next two or three hours, we witnessed a
spectacle which can never fade from my memory. The shooting stars gradually
increased in number until sometimes several were seen at once... All of the
tracks of the meteors radiated from Leo... Occasionally luminous trains
would linger on for many minutes after the meteor had flashed across, but
the great majority of the trains in this shower were evanescent. It would be
impossible to say how many thousands of meteors were seen, each one of which
was bright enough to have elicited a note of admiration on any ordinary
night."
Giovanni Schiaparelli
of Italy commented in a letter written in 1867 that Comet Tempel-Tuttle was
probably related to the Leonid meteor stream. Camille Flammarion wrote that
"for the swarm of shooting stars of November... Le Verrier has
calculated that it entered for the first time into our system in the year
126 of our era, at a point near where the planet Uranus was then situated,
and that it is this planet which has transformed the parabolic into an
elliptic orbit. If the planet had not been there, the meteors would have
continued their course".
iii) Observations This
Century....
In 1933, no storm was
observed.
In 1966, however, a
brief storm was observed on November 17th over the central and western
United States. Dennis Milon is quoted on http://leonid.arc.nasa.gov/history.html
regarding the observations from Kitt Peak, Arizona:
"The meteors were
so intense that we were guessing how many could be seen in a one-second
sweep of the observers head."
A peak rate of about
40 meteors per second was reached at 5.54 a.m. local time. This works out to
2400 meteors per minute, or 144,000 meteors per hour!
In 1998, a surprise
shower of fireballs was seen. A summary can be found at http://star.arm.ac.uk/~ambn/abstract309.html,
from a paper by Asher, Bailey and Emel'yanenko titled 'Resonant meteoroids
from Comet Tempel-Tuttle in 1333: the cause of the unexpected Leonid
outburst in 1998''. This unexpected bombardment of fireballs happened about
16 hours before the predicted peak of the Leonid shower! It must be
remembered that, in spite of all kinds of predictions by professional
researchers, that we still do not know everything about meteors! This is why
it is so important to watch on a number of nights - from wherever you happen
to be around the globe.
In 1999, a storm of
Leonid activity was observed from western Asia, Europe, and Africa, with ZHR
rates of about 3700 meteors per hour. Details are given in the IMO analysis
at http://www.imo.net/articles/shower/leo99.html. The IMO states that the
Leonid storm component had 'an unusual magnitude distribution with a lack of
both very bright and very faint meteors'.
In 2000, rates were
not as high. Three peaks were observed, but with ZHR rates only about 130,
290 and 480 meteors per hour respectively, as per the IMO analysis.
iv) Leading Up to
Recent Analyses...
According to Gary
Kronk on his "Comets and Meteor Showers" website:
"The most
ambitious study of the relationship between Tempel-Tuttle and the Leonids
was published in 1981. Donald K. Yeomans... mapped out the dust distribution
surrounding Tempel-Tuttle by 'analyzing the associated Leonid meteor shower
data over the 902-1969 interval'. He noted that most of the ejected dust
lagged behind the comet and was outside its orbit... Yeomans suggested this
indicated 'that radiation pressure and planetary perturbations, rather than
ejection processes, control the dynamic evolution of the Leonid particles'.
Concerning the occurrence of Leonid showers, Yeomans said 'significant
Leonid meteor showers are possible roughly 2500 days before or after the
parent comet reaches perihelion but only if the comet passes closer than
0.025 AU inside or 0.010 AU outside the Earth's orbit'. He added that
optimum conditions will be present in 1998-1999, but that the lack of
uniformity in the dust particle distribution still makes a prediction of the
intensity of the event uncertain."
v) Predictions for
This Year...
There are a number of
models predicting the activity of the Leonid meteors this year. It will only
be after the event has occurred that we will know which model best fits the
activity seen! Hence it is really important for all observers to monitor the
nights around November 17th and 18th and 19th - before the maximum, during
the maximum, and after the maximum. Surprises can always occur. Consider the
fireballs of 1998 - they arrived the night before anyone was expecting major
Leonid activity!
According to the
Armagh Observatory website - the predictions of Robert McNaught of Australia
and David Asher of Armagh - the times of maximum Leonid activity and the
estimated meteor rates are as follows, quoted from http://www.arm.ac.uk/leonid/encounters.html
Date Time ZHR rate
Visible from
1. Nov. 18 10.01 UT
2,500/hr ? N. & Central America ie. debris shed by the comet in 1767, 7
'revolutions' ago in its trip around the sun
2. Nov. 18 17.31 UT
9,000/hr Australia & E. Asia ie. debris shed by the comet in 1699, 9
'revolutions' ago in its trip around the sun
3. Nov. 18 18.19 UT
15,000/hr W. Australia, E., SE & Central Asia ie. debris shed by the
comet in 1866, 4 'revolutions' ago in its trip around the sun
(Peaks have been
numbered 1, 2 & 3 for quick reference to other models mentioned below,
for the same debris streams.)
The time is given in
UT, Universal Time. This is the time in Greenwich, England - so count over
the hours to get to your own time zone! For observers on Eastern Standard
Time, it is 5 hours earlier - ie. for the above, using the 24 hour system:
05.01, 12.31 and 13.19, or in normal clock time: 5.01 am, 12.31 pm, and 1.19
pm. For observers on Pacific Time, it is 8 hours earlier - ie. for the
above, using the 24 hour system: 02.01, 09.31 and 10.19, or in normal clock
time: 2.01 am, 9.31 am, and 10.19 am. Time is tricky - so be careful. You
can see from these times that North America only gets 1 peak at night.
Note that Australia
and Asia are on the other side of the International Date Line - so the
storming predicted over there actually happens in the pre-dawn hours of
November 19th, not the 18th.
ZHR refers to the
Zenithal Hourly Rate, the number of meteors that an observer would see, on
the average, per hour, with the unaided eye, if they were out under a dark
country sky, and if the radiant, the area in the sky where the meteors seem
to come from, was directly overhead. We will be close to new moon for
Leonids, so that is good. Get out to a dark site to increase your meteor
rates! However, your latitude will affect how high the Leonid radiant will
get in your sky - and that will affect your rates as well.
A diagram showing
these 3 Leonid 'dust trails' is on the Armagh website at http://www.arm.ac.uk/leonid/info2001.html.
It is interesting to note that the dust trails for 1699 and 1866 will appear
very close together for us from the earth's viewpoint - and it could be
difficult to tell them apart! It is also noted on the site that smaller
contributions of dust from the 10 revolution debris and
the 11 revolution debris will add to meteors seen from the 9 revolution and
4 revolution debris! (It will be very interesting for those doing meteor
photography or video to see if there is a noticeable difference in radiant
position for these different overlapping dust trails, as seen from the
earth!) And - the cumulative effect of all these meteor rates could be quite
phenomenal.
Another Leonid model,
that of Esko Lyytinen, Markku Nissinen and Tom Van Flandern, predicts, as
quoted from http://www.saunalahti.fi/~fmbb/astro/2001leonidstorm.htm
1. Nov. 18 10.28 UT
2,000/hr N. & Central America (7-rev) 2. Nov. 18 18.03 UT 2,600/hr W.
Australia, E., SE & Central Asia (9-rev) 3. Nov. 18 18.20 UT 5,000/hr W.
Australia, E., SE & Central Asia (4-rev) & smaller peaks at: Nov. 18
12.00 UT 110/hr (6-rev) Nov. 18 14.10 UT 60/hr (5-rev) Nov. 18 19.10 UT
150/hr (10 rev) Nov. 18 19.10 UT 150/hr (11 rev)
Another Leonid model,
that of Peter Jenniskens, predicts, as quoted from http://leonid.arc.nasa.gov/1998.html
1. Nov. 18 10.09 UT
4,200/hr N. America (7-rev) 2. Nov. 18 17.08 UT 1,800/hr Australia, E. Asia
(9-rev) 3. Nov. 18 17.55 UT 2,700/hr Australia, E. Asia (4-rev) &
smaller peaks at: Nov. 18 12.07 UT 40/hr Western USA/ Hawaii (6-rev) Nov. 18
13.57 UT 14/hr Western USA/ Hawaii (5-rev) Nov. 18 17.01 UT 170/hr
Australia, E. Asia (10-rev) Nov. 18 17.21 UT 510/hr Australia, E. Asia
(11-rev)
Another Leonid model,
that of Peter Brown and Bill Cooke, predicts, in the September 2001 issue of
the "Monthly Notices of the Royal Astronomical Society", as
paraphrased by Gary Kronk at http://comets.amsmeteors.org/meteors/showers/leonidprediction.html
"that a 'broad and relatively strong' maximum will occur with a peak of
possibly more than 1200 meteors per hour falling down between 10 and 12 UT.
A much broader secondary maximum could occur around 17:30 UT with rates near
500 per hour."
Looking at the article
by Bill Cooke on the Space Environments & Effects Program website at http://see.msfc.nasa.gov/see/Leonid_Forecast_2001.html, you can see this
graphically by looking near the end of the article at the diagram
"Revised Brown/Cooke 2001 Forecast". This multi-color graph gives
a line for each of the debris streams - 1633, 1666, 1699, 1733, 1766, 1799,
1833, 1866 - and a line showing the total predicted activity as a result of
the earth passing through all of this debris combined.
Can you see Leonid
meteors at other times besides those listed above? Of course you can! As
quoted from the Armagh website:
"You can view the
background of the Leonid meteor shower at other times, basically between
your own local midnight (exact time being latitude dependent) and morning
twilight; it's just that you'll miss the encounters of the Earth with
meteors from these particular dust trails if you're not in the parts of the
world on these maps."
The maps - of where to
be on the earth to see meteor storming due to the dust trails - are at http://www.arm.ac.uk/leonid/info2001.html. The total activity period for the
Leonids is listed by the IMO, the International Meteor Organization, as
November 14th to 21st. The dust trails are predicted to be seen at the
specific times listed in the various models. We won't know whose model best
matches the Leonid dust trail activity until after the meteors are seen! But
the overall background Leonid meteor activity will be seen for a much longer
period of time - before, during, and after the 'storming' due to the dust
trails.
vi) Where Should You
Go?...
Your priority as to
where to observe Leonids from should be - first and foremost - a site where
the skies will be clear! Many observers plan to travel - but all
observations worldwide are valuable, as data is needed from as many
different longitudes as possible to get complete global coverage.
vii) What Should You
Record?...
What should you
record? Check out our NAMN Observing Guide at http://www.namnmeteors.org/guide.html
If you need a set of star charts showing the constellations, sky
coordinates, and the magnitudes of stars useful in judging the brightness of
the meteors you see, print yourself off a set from http://www.namnmeteors.org/charts.html.
For a set of star
charts to use in judging how good your perception is, and how good your sky
is (your limiting magnitude, LM), print off a selection of charts from http://www.imo.net/visual/major01.html#table2.
For the storm
components of the Leonids, plan now. Life will be fast and furious - and
your normal observing methods may not work.
Check out Sirko
Molau's meteor storm simulation. It can be downloaded from ftp://ftp.imo.net/pub/software/metsim/
Give some thought now as to how you would deal with this. If you continue to
record visually, you may have to estimate batches of meteors per time unit,
and give up estimating magnitudes. You may decide to forego visual counting
- and take timed photographs instead. You may decide to run a video camera.
If recording by camera or video - be sure to accurately note your start and
stop times - in order for your data to be useful scientifically.
For more information
on meteor photography, check out http://www.imo.net/photo/index.html
For more information
on video recording, check out http://www.imo.net/video/index.html. Keep in
mind that only a handful of observers around the globe have the special
'intensified' video cameras that are talked about. However - due to the
special nature of this year's Leonids - if you have a video camera of any
kind, use it! All video coverage of this event, from as many observers
around the globe as possible, will be useful. For more information, or
questions concerning recording meteors by video, contact the IMO,
International Meteor Organization, Video Commission Director, Sirko Molau,
at video@imo.net.
viii) Where in the Sky
Should You Look?...
For the 'storm'
components of the Leonids, we doubt that you will have a problem recognizing
the Leonid meteors. However, in the quiet nights leading up to the maximum,
and after the main weekend, you may need some info on where to look. A map
showing the movement of the Leonid radiant over time can be found at http://www.imo.net/calendar/cal01.html#Leonids.
The Leonids (LEO) will
have a general radiant at 153 degrees, ie. RA 10h 12m, Dec +22, which is
about 2 degrees down to the right of the star zeta Leonis, the star called
Adhafera, up in the 'sickle' of Leo. No matter where in the sky you see
them, if you trace back the path of a Leonid meteor, it will seem to come
from this area.
The radiant is an
area, not just a point in the sky. In fact, with the earth intersecting
several dust trails this year, there will be slight differences in radiant
position. These may or may not be noticeable by a visual observer - but
would show up in detailed photographic or video observations.
These are very fast
meteors, with a velocity of about 71 km per second. Get comfortable in your
lawnchair, and center your gaze about 50 degrees up in the sky. As these
meteors are very fast, the fainter ones may be difficult to detect for
beginning observers. If you concentrate on one direction in the sky, instead
of moving all over, you will have a better chance of seeing more meteors,
especially the fainter ones. And - a dark country sky is important!
ix) How to Stay Tuned
to Leonids as They Happen...
How can you stay tuned
to the shower activity as it happens around the globe? Watch our "Meteorobs"
email list. It is the best source in town! If you are reading this
newsletter, and are not yet on our email list, consider subscribing so that
you too can hear the latest Leonid happenings! To subscribe, go to our
Subscriber form at http://www.meteorobs.org/subscribe.html.
We are interested in
hearing all Leonid meteor reports! Drop an email either to the list or to
our NAMN Coordinator at SC.meteors@home.com
2. A Leonid
Checklist...
What do you need to
observe the Leonids? The following is a basic checklist for those planning
to observe this incredible meteor shower:
Warmth and comfort
gear: - a reclining lawnchair so you can lie back in comfort - a foam mat to
put on your lawnchair to insulate your back - a heavy sleeping bag - extra
blankets - a tarp to put over your sleeping bag to keep frost or dew off -
long underwear, then layers of warm clothing - a warm coat - warm wool socks
- take your boots off - warm mittens or gloves, and extra mittens - wool hat
- a scarf to wrap around your neck and face - handwarmers - cookies for a 3
a.m. snack - thermos of tea or coffee
Recording tools: -
paper and pencil and meteor recording sheets - spare pencils - preferably,
pocket tape recorder, with paper as a backup - if recorder, spare tapes and
spare warm batteries - red flashlight - and a spare red flashlight - watch
or clock set to UT, Universal Time - star charts showing 'standard stars' to
judge meteor magnitude - star charts to estimate LM, limiting magnitude of
sky
To take still photos
of Leonids: - a camera with bulb, ie time exposure, setting - a normal or
wide angle lens - a tripod - a cable release - fast film, preferably ASA 400
or higher - some method of keeping frost or dew off your lens - a watch to
time your photos (important) - a notebook to record your exposure start and
stop times
To take video of
Leonids: - a video camera with lots of spare battery packs - a tripod - a
watch to time your video clips (important) - if there is a time marker on
your tape, set it properly ahead of time - a notebook to record your
exposure start and stop times
To see what the
fainter Leonids look like near the radiant, or to look at Leonid meteor
trains: - a pair of binoculars
To help spread the
word about meteors: - bring your friends and family - the Leonids could be a
once-in-a-lifetime experience!
3. Other November
Showers...
The Orionids (ORI),
debris from Halley's Comet, although having reached a maximum on October
21st, can be seen until about November 7th. On November 5th, the radiant
will be at 105 degrees, ie RA 7h 00m, Dec +17, which is about 5 degrees to
the left of the star gamma Gemini, the star known as Alhena. These are fast
meteors, with a velocity of about 66 km per second. ZHR rates will be low,
far less than the 20 meteors per hour seen back at maximum in October. A map
showing the movement of the Orionid radiant can be found at http://www.imo.net/calendar/cal01.html#Orionids.
The Orionid radiant is the line labelled ORI.
The southern Taurids (STA)
reach a maximum on November 5th, with a radiant at 052 degrees, ie RA 3h
28.2m, Dec +13, which is about a degree to the right of the star 5 Tauri on
a star atlas. These are slow meteors, with a velocity of about 27 km per
second. ZHR rates at maximum will be about 5 meteors per hour. They can be
seen in lesser numbers until about November 25th.
The northern Taurids (NTA)
reach a maximum on November 12th, with a radiant at 058 degrees, ie RA 3h
52.2m, Dec +22, which is about 2 degrees down to the left of the Pleiades
star cluster. These are, like the southern Taurids, also fairly slow
meteors, with a velocity of about 29 km per second. ZHR rates are also
similar, with about 5 meteors per hour. These can also be seen until about
November 25th. A map of the northern and southern Taurid radiants can be
found in the IMO calendar for 2002, at http://www.imo.net/calendar/cal02.html#Taurids.
The alpha Monocerotids
(AMO) are a special shower - and should be monitored. They have variable
rates, and have been known to outburst in the past. They reach a maximum on
November 21st, with a radiant at 117 degrees, ie RA 7h 48m, Dec +01, which
is about 4 degrees down to the left of the bright star Procyon in Canis
Minor. They are fast meteors, at about 65 km per second, and can be seen
from about November 15th to 25th. A map showing the radiant can be found at http://www.imo.net/calendar/cal01.html#alpha-Monocerotids.
The chi Orionids (XOR),
although not reaching a maximum until December 2nd, can be seen starting
about November 26th. On November 30th, the radiant will be at 080 degrees,
ie RA 5h 19.8m, Dec +23, which is about 1 degree north of the star 109 Tauri
on a star atlas. These are fairly slow meteors, at about 28 km per second.
Rates at the maximum on December 2nd will be about 3 meteors per hour, but
in late November, fewer will be seen. For a map of the radiant positions,
see the IMO calendar for 2000 at http://www.imo.net/calendar/cal00.html#chi-Orionids.
The Phoenicids (PHO),
although not reaching a maximum until December 6th, can be seen starting
about November 28th. On November 30th, the radiant will be at 014 degrees,
ie RA 0h 55.8m, Dec -52, which is about 34 degrees south of the star beta
Cetus, known as Diphda, and will only be seen by more southerly observers.
These are very slow meteors, at about 18 km per second. ZHR rates are
variable, so can provide some surprises. The radiant, although very far
south, can be seen on the map at http://www.imo.net/calendar/cal01.html#Phoenicids.
Lastly, the
Monocerotids (MON), although not reaching a maximum until December 9th, can
be seen starting about November 27th. On November 30th, the radiant will be
at 091 degrees, RA 6h 4.2m, Dec +8, which is about 2 degrees to the left of
the star Betelgeuse in Orion. These are average velocity meteors, at about
42 km per second. ZHR rates at maximum will be about 3 meteors per hour, and
November rates less. A map of the radiant is at http://www.imo.net/calendar/cal01.html#Geminids.
The Monocerotid radiant is the line labelled MON.
For extra reading on
any of these showers, or to read about other minor showers not on the IMO
"Working List of Visual Meteor Showers", check out Gary Kronk's
"Comets and Meteor Showers" website at http://comets.amsmeteors.org.
To see movie clips of sample comets and meteors, check out Kronk's
'Education Corner'.
Besides recognized
showers, there is also sporadic meteor activity in November, about 7 meteors
per hour, visible to the unaided eye. This activity is comprised partly of
random meteor activity and partly of meteors that belong to long-ago, now
untraceable showers.
Full moon this month
is on Thursday November 1st - and is called the Hunter's Moon. Last quarter
is on Thursday November 8th. New moon is on Thursday November 15th - just
before the Leonids. First quarter is on Thursday November 22nd.
For use in judging the
brightness of the meteors you see this month, the magnitudes of the planets
are as follows (to the nearest half magnitude for most of the month):
Venus -4 in the
morning sky Mercury -1 in the morning sky Jupiter -2.5 visible all night in
Gemini Saturn -1 visible all night in Taurus Mars 0 in the evening sky in
Capricornus
For more info on the
moon and planets, check out http://www.heavens-above.com, "Select"
your location, and then check out the options. On Saturday November 3rd at
22h UT, Saturn will be 0.6 degrees south of the moon, with an occultation
visible from Europe, the British Isles, NW Africa, the Arctic, Russia, and
Japan. This website is also useful in determining the identity of satellites
you will see while meteor observing!
Astronomy
Club of Tulsa,
918.688.MARS
President:
John Land
Vice
President: Dennis Mishler
Secretary:
Teresa Kincannon
Treasurer:
Nick Pottorf
RMCC
Observatory Manager: Gerry Andries
Observing
Chairman: David Stine
Web
Master: Tom McDonough
New
Membership: Dennis Mishler
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