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(meteorobs) NAMN Notes: October 1999

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NAMN Notes: October 1999
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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://web.infoave.net/~meteorobs

Contents:

1. October Showers & New Moon Weekend...
2. Plan Ahead for the Leonids...
3. Meteor Results from August...
4. Upcoming Meetings...
5. Observing Partner Wanted...
6. For more info...


1. October Showers & New Moon Weekend...

The Draconids, also known as the Giacobinids (GIA), reach a maximum on
October 9th, but can be seen from about the 6th to the 10th. This shower is
favorable this year as far as the moon goes as new moon is on Saturday the
9th. This is a weekend, so is great for observing for all most of us! The
radiant at maximum will be at 262 degrees, ie. RA 17h28m, Dec +54, which is
just north of the star beta Draconis, also known as Restaban, in the head of
Draco. These are slow meteors, at about 20 km per second. The strength of
this shower has varied greatly over the years, reaching 'storm' level in
1933 and 1946. According to the IMO, the International Meteor Organization,
"so far, detectable activity has only been seen in years when the stream's
parent comet, 21P/Giacobini-Zinner, has returned to perihelion. It did this
last in 1998 November." This is, however, a shower with quite a reputation,
albeit variable, and is well worth your observing efforts!

The delta Aurigids (DAU) reached a maximum in early September, but can be
seen until about October 10th. At maximum, the ZHR rate is about 6 meteors
per hour, but October rates will be low. These are fast meteors, with a
velocity of about 64 km per second. The radiant on October 10th will be at
95 degrees, ie RA 6h20m, Dec +49, which is very near the star psi#1 Auriga
on a star atlas. There is a questionable link between these meteors and
Comet Bradfield, C/1972 E1.

The epsilon Geminids (EGE) come to maximum on the 18th, near first quarter
moon, with activity stretching from the 14th to 27th. The radiant on the
18th is at 102 degrees, ie. RA 6h48m, Dec +27, which is several degrees
north of the star epsilon Gemini, also known as Mebsuta. These are fast
meteors, at 70 km per second, and at maximum may reach a ZHR rate of about 2
meteors per hour. The parent body is theorized to be either possibly Comet
Ikeya, C/1964 N1, or Comet Nishikawa-Takamizawa-Tago, C/1987 B1.

The Orionids (ORI) have a maximum on October 21st this year, just before
full moon on the 24th. Activity can be seen from this shower all month. On
the new moon weekend, the radiant on October 10th will be at 88 degrees, ie
RA 5h52m, Dec +15, which is very near the star 135 Taurus, about 7 degrees
north of Betelgeuse in Orion. At maximum on the 21st, the radiant will have
moved to 95 degrees, ie. RA 6h20m, Dec +16, which is almost in the foot of
Gemini, about 4 degrees to the right of the star gamma Gemini, the star
Alhena. These are fast meteors, at about 66 km per second, and many of the
meteors have trains left behind. The ZHR, Zenithal Hourly Rate, is about
20 meteors per hour visible with the unaided eye under dark skies when the
radiant is directly overhead. Unfortunately, the presence of moonlight will
reduce the number of meteors seen considerably. These meteors are debris
from Halley's Comet, and are a dependable annual shower.

The Taurid showers are also active - both the Northern Taurids (NTA) and
the Southern Taurids (STA), although they do not reach maximum rates until
early November. Both of these showers have meteors considered to be slow -
the NTA's are about 29 km per second and the STA's about 27 km per second.
Rates for both showers reach a ZHR maximum in November of about 5 meteors
per hour, so rates in October will be low. On October 10th, new moon
weekend, the NTA radiant will be at 29 degrees, ie RA 1h56m, Dec +14, which
is about 7 degrees south of the star beta Aries, known as Sharatan, and the
STA radiant will be at 31 degrees, ie RA 2h4m, Dec +8, about 5 degrees north
of the star alpha Pisces. There is a group of objects possibly associated
with this meteor stream, as parent or sibling bodies, including Comet Encke,
and the splitting of these bodies is theorized to have perhaps happened as
long ago as 100,000 years in the past, depending on which theories are
considered.


2. Plan Ahead for the Leonids...

Now is the time to think seriously about your observing plans for the Leonid
meteor shower coming up in mid-November!

According to the professionals, there is a good chance that the Leonids
could 'storm', with thousands of meteors visible. If it does storm, the
predictions seem to favor a European longitude as far as location goes.
However, meteor showers can be very unpredictable, and nobody will know for
sure what the Leonids will actually do until it happens!

Should you try to travel to see this shower? Many people are planning to do
just that. However, it is also very important from a global perspective to
get as many observers as possible scattered around the world - covering all
bases as it were - to gather observations at widely separated locations and
times, both in the days leading up to the shower, and the days afterwards.
So, if you are unable to travel - you are still extremely valuable as an
observer!

Give serious thought as to what types of observations you want to do for the
Leonids - and plan now. Do you want to do visual observations, or perhaps
some photography as well? Do you have a video camera? Perhaps you might
want to have that running during your observing session too. It will be
almost winter by mid-November, so plan for cold nights, and get your winter
gear ready now.

Check out the web resources on the Leonids. Perhaps the best single place
to start is Dr. Peter Jenniskens' Leonid homepage, at:
http://leonid.arc.nasa.gov. It has a wide variety of information, including
details on the '99 Leonid Multi-Instrument Aircraft Campaign, and such
things as a Teacher's Corner, and a Media Center for Leonid information.

The "Links" section on Dr. Jenniskens website is excellent, and connects you
to information on the meteor shower, how to observe it, the parent comet,
history of the shower, recent observations, the satellite hazards, news
stories, reports of the airborne experiments, related science news and
personal stories. Articles relating to 1998 will be updated when 1999 info
becomes available. Both make fascinating reading. Some of the topics covered
in these links include:

1999 - general information:
Leonids on the horizon: what is in store for 1999 (NASA/MSFC)
Basic data (NASA/ARC)
Basic parameters (Aerospace Corp.)
Leonid High School project worldwide (Japan)

Observing guides:
Observing guide for researchers (NASA/ARC)
Leonid viewing tips (StarDate Online)
Observing guide to the Leonids (IMO)
Meteor observing guide (NAMN)
Leonid pages (Gary Kronk)
Leonid media guide (Peter Jedicke - University of Western Ontario)
Leonid site of Aerospace Corp.
Leonid Storm Watch (SETI Institute)

Comet 55P/Tempel-Tuttle:
55P/Tempel-Tuttle image archive (NASA/ARC)
Biography of Wilhelm Tempel - the discoverer of the Leonid shower parent
body

Leonid shower history:
A brief Leonid shower history (NASA/ARC)
Leonids 1833: The Night of Raining Fire (Sky & Tel.)
The Leonids, King of the meteor showers (J. Rao, Sky & Tel.)
Leonid shower observations: 1833 to present (G. Kronk)
Ancient Leonid shower observations (G. Kronk)

Reports on 1998 observations:
1998 Leonid news (NASA/ARC)
Images and Video of Leonid MAC (NASA/ARC)
The return of the Leonid meteors (Rao - Sky & Tel.)
Sino-Dutch Leonid campaign - many photos/video (Dutch Meteor Society)
Leonid meteors in Mongolia (Daniel Fisher, science writer)
The '98 Leonids at ESA's European Space Operations Center
Leonids in China (UK-China expedition)
1998 Leonids from Slovakia
Leonid fireball train captured by ROTSE
Green Leonid fireballs Nov. 16/17, Missouri

Satellite impact hazard:
The Leonid Storm Fluence Calculator (NASA/MSFC)
The Upcoming Leonid Meteoroid Storm and its Effect on Satellites (Aerospace
Corp.)
Meteor Storm Hazard - Leonids '98 (CresTech - Canada)

News stories from 1998 Leonids:
The Leonids are coming, the Leonids are coming! (ScienceNews Online)
Leonid meteor storm won't deter Hubble (Astronomy Online)
Space news: Leonid mania
Mir cosmonauts deploy meteoroid trap during spacewalk
Leonid Meteors Provide Test Opportunities For Starfire Optical Range
Meteors get glowing reviews (San Jose Mercury News - Glennda Chui)
New Mexicans enjoy heavenly light show (AP - Louinn Lota)
Leonid Fireballs dazzle the world (Sky & Telescope)
Satellites survive meteor shower (Washington Post)
Whatever happened to the Leonid meteor shower (Christian Science Monitor)
Did the Leonid storm peak early? (The Hindu)

Leonid MAC news:
NASA Astrobiology to shower attention on Leonids (NASA/ARC)
Research aircraft fly below once in a century Leonid meteor storm (NSF)
Edwards aircraft lifts scientists for Leonid view (USAF/425nd FTS)
Boulder Scientists going to Japan (Stern, SWRI)
Researchers to study Leonids meteor shower from F-15 aircraft (Astronomy
online)
Leonid Multi-Instrument Aircraft Campaign a Resounding Success (NASA/ARC)

Science news:
Leonids give Moon a sodium bath
Leonid 1998 fireballs explained
Leonid broad component from 1333 ejecta
Video of 1997 Leonid meteor that fragmented before entry in Earth's
atmosphere
Effect of organics in meteors on visibility (D. Steel)

Personal stories:
The Leonid MAC (webcast) - Dr. Peter Jenniskens
Mongolia expedition - Lt. Tiffany Montague
Observing from China (Paul D. Maley)
Observing from Hawaii (Bill Harby)

These are just some of the articles available. Many more will be added for
1999.

So, start reading up on the Leonids now, and give serious thought as to
what you would like to do to observe them! If you are an experienced
observer, you will be making fairly specific plans.

If you are a new observer, or perhaps just discovering what meteors are all
about, don't be discouraged though by all the technical talk. It is more
important to just plan to watch the Leonids - and show your friends, your
family and your children what an incredible sight a meteor shower can really
be!

That's November 16/17/18.... mark your calendars now!


3. Meteor Results from August...

What a month!! Warm summer evenings and family vacations almost always
guarantee that August will be the most active month for meteor observers,
and this year was no exception. Just like in July, 18 nights were monitored
by members during the month. A total of 168 hours of observations were
reported, which is over twice the number from July! The number of members
participating in watches also doubled with 26 of our members contributing
reports in August compared to 12 in July. Finally, a total of 3,541 meteors
were recorded by observers. With all those meteors arriving, let's see how
they broke down...

By far, the most active shower was the Perseids with 2,222 being recorded in
August. This total certainly would have been higher if the poor weather had
not developed in much of the eastern portions of North America. Add that to
the 48 observed last month makes this the most active shower of the year for
NAMN members. Additionally, August was the first month this year in which a
meteor shower produced more meteors than the sporadic meteors. In August,
1,079 sporadic meteors were recorded by members.

Several other showers were also reported in August. Below is a list of them
with the number of meteors reported in parenthesis. Note that the meteors
reported as Aquarids are meteors that were not separated into their northern
and southern branches.

Alpha Capricornids (25)               Alpha Cygnids (1)
Aquarids (39)                         Northern Delta Aquarids (68)
Southern Delta Aquarids (27)          Northern Iota Aquarids (13)
Southern Iota Aquarids (19)           Kappa Cygnids (42)
Piscis Austrinids (6)

The following NAMN members sent reports in during August:

Dean Bauer                           Larue Miller
Louis Binder                         Scott Moser
Michael Boschat                      Eric Palmer
Joey Cross                           Gregg Pasterick
Peter Detterline                     James Smith
George Gliba                         Wanfang Song
Wayne Hally                          Yuying Song
Kim Hay                              Chris Stephan
Kevin Kilkenny                       David Swann
Robert Lunsford                      Harry Waldron
Pierre Martin                        Ying Wang
Norman McLeod                        Kim Youmans
Mark Mikutis                         Ju Zhao

I would like to thank each of these observers for their efforts in August
and for sending their reports in for archiving. I encourage everyone to join
us in the remainder of our 1999 observing campaigns. If you are new to
observing and uncertain how to begin, now is the time to gear up for the
upcoming active meteor season of October, November and December. Send us an
email if you need assistance or forms.


4. Upcoming Meetings...

January 10-13, 2000:
The 38th annual Aerospace Sciences Meeting & Exhibit of the AIAA, American
Institute of Aeronautics and Astronautics, will be held in Reno, Nevada. A
special session on meteors has been proposed, called 'Aerothermochemistry
effects in meteoric plasmas' and will be chaired by meteor astronomer Dr.
Peter Jenniskens of The SETI Institute at NASA/Ames Research Center, and
co-hosted by plasma physicists Dr. Olga Popova of the Moscow Institute for
Dynamics of Geospheres RAS and Dr. Iain Boyd of the Department of
Aerospace Engineering of the University of Michigan. This is an opportunity
for the plasmadynamics, thermophysics, and fluid dynamics communities to
learn more about the physics, aerochemistry, and optical diagnostics of
meteoroids. Information on the conference can be found on the website at:
http://www.aiaa.org/calendar/asm00cfp.html.


5. Observing Partner Wanted...

We received this observer request:

"I would like to participate in any group observing the Leonids in November
from Egypt to the South of Cairo, I would like contact on "colo@zeta.org.au
John Burke Sydney Australia"

If anyone is lucky enough to be in Egypt during this time, you might
consider dropping John a note.


6. For more info...

Contact:
Mark Davis, MeteorObs@charleston.net
Mt. Pleasant, South Carolina, USA
Coordinator, North American Meteor Network

And check out:
NAMN home page:
http://web.infoave.net/~meteorobs
Back issues of NAMN Notes can be found on-line at the website.

To subscribe to the meteor email list or
To find out information on our weekly chat sessions:
Contact Lew Gramer at:
owner-meteorobs@jovian.com

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Here's to 'Clear Skies' for October!...

October 1999 NAMN Notes co-written
by Mark Davis and Cathy Hall
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