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(meteorobs) NAMN Notes: May 2001
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NAMN Notes: May 2001
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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.infoavedot net/~meteorobs
Contents:
1. Eta Aquarids - Debris from Halley's Comet...
2. Other Showers Visible in May...
3. Recent Observations...
4. Elmo Does Meteors - How to Interest Kids...
5. Upcoming Meetings...
6. For more info...
1. Eta Aquarids - Debris from Halley's Comet...
The eta Aquarid (ETA) meteor shower reaches a maximum on May 5th this year,
at about 23 hours Universal Time (UT). This is a particularly interesting
shower as it is debris from the famous Halley's Comet.
These are fast meteors, travelling at about 66 km/sec, and will seem to come
from an area in the sky located at 338 degrees ie. RA 22h 31.8m, Dec -01,
which is very near the star eta Aquarius on a star atlas. This is known as
the radiant for the shower. Check out the maps of the sky on the NAMN
website
at http://web.infoavedot net/~meteorobs/charts.html. Aquarius is on Map #3,
and can be printed off by setting your printer to landscape mode. Also
check out the map of the eta Aquarid radiant itself, on the International
Meteor Organization (IMO) website at the following address:
http://www.imodot net/calendar/cal00.html#eta-Aquarids. The radiant moves a
little bit from night to night.
The Zenithal Hourly Rate (ZHR) for this meteor shower is about 60 meteors
per hour with the unaided eye. This is the number of meteors, on average,
that an observer would see from a dark country sky if the radiant
was directly overhead. Your latitude and your time of night will affect
your meteor rates, as they affect how high the radiant is in your sky.
Unfortunately, we also have a bright moon for this year's eta Aquarids, so
the faintest meteors will not be seen. Eta Aquarid meteors can be seen in
lesser numbers until about May 28th.
However, it is still a treat to see this comet debris! Try to block the
moon from your field of view. This will help you see more meteors. The
nights around the date of maximum are also worth observing, besides just
the main night, as there may be some other small peaks of meteor activity,
perhaps even until about May 10th. You can help us out by trying to get
data for some of these other nights.
Each one of these meteors is a streak of light produced when a small
particle of debris from Halley's Comet strikes our Earth's upper
atmosphere and burns up due to friction. These particles have been shed by
the parent comet many years ago. In fact, each time the comet passes
through our solar system, a new path of debris is created. The path of
debris that we encounter in one year might not be the same filament of
debris that we encountered in a previous year. This is one reason why
meteor shower rates can vary from year to year.
For more information on what to record when you watch meteors, check out
our NAMN Observing Guide at: http://web.infoavedot net/~meteorobs/guide.html.
If you have any questions, drop a note to our NAMN Coordinator at
MeteorObs@charlestondot net
For information on Halley's Comet - the parent of these wonderful eta
Aquarid meteors - check out Gary Kronk's Comets and Meteor Showers website
at http://comets.amsmeteors.org.
2. Other Showers Visible in May...
The Sagittarids (SAG) continue to represent the ecliptic activity - the
meteor activity whose radiant moves along the path of the ecliptic in the
sky, or along the constellations of the zodiac as they are known to many of
the public.
These have a velocity of about 30 km per second, so they are much slower
that the eta Aquarids. The ZHR rate for this activity is about 5 meteors per
hour. On May 5th, the radiant will be at 236 degrees, ie. RA 15h 43.8m,
Dec -20, which is near the star kappa Libra, about 5 degrees to the right of
the top of the "J" in Scorpius. By May 30th, the radiant will have moved to
256
degrees, ie. RA 17h 4.2m, Dec -23, which is about 8 degrees up to the left
of the reddish star Antares.
Fireballs are possible with this shower, so the patient observer is often
rewarded with nice, bright meteors.
There are other meteor showers in May. However, according to the IMO "during
May and June, most of the activity is in the daytime sky, with six shower
peaks expected during this time." If you are interested in trying to observe
meteors by radio, check out the IMO website at http://www.imodot net for more
information.
Full moon this month is on May 7, last quarter on May 15th, new moon on May
23rd, and 1st quarter on May 29th. Jupiter is low in the western sky at
magnitude -2.0 and Venus is in the morning sky at about magnitude -4.5 for
most of the month.
Some useful star charts can be printed off from our NAMN website. These
show the constellations, the RA and Dec star coordinates, and the
brightness of certain standard stars to help you judge the magnitudes of the
meteors you see. This set of 4 charts is available at:
http://web.infoavedot net/~meteorobs/charts.html.
Don't forget that - regardless of what meteor showers are visible - there
is always sporadic meteor activity, meteors that are random or belong to
long ago, untraceable meteor showers. Every hour and from anywhere in the
sky, you will see an average of about 7 of these meteors.
You will also see satellites, and lots of them. You can make a note of
where you see them, and check out their identity after your observing
session is over. Or you can check out a satellite website ahead of time,
and take a list with you of which ones to watch for! The best satellite
website is http://www.heavens-above.com. Pick your country, then your
nearest town, and it will give you a list of all the brightest satellites
you can see. Don't forget - the smaller the number, the brighter the
satellite. If something is about magnitude 2.0, then it is about the
brightness of the stars in the Big Dipper. If it is magnitude 5, it is
faint. If it is magnitude 0 or a negative magnitude, it is bright!
May observing is a great time of year - warm enough to be comfortable, and
yet pleasant before the mosquitoes of summer appear. Take out a lawnchair
and sleeping bag, and enjoy the meteors of spring!
3. Recent Observations...
Only two NAMN members braved the cold weather of February to search out
meteor activity. Harry Waldron of Virginia sent in a negative report
indicating he was clouded out during his planned sessions, and saw no
meteors at all. Lew Gramer, veteran of many cold observing sessions in
Massachusetts, decided to play it smart and take off for the warmth and fun
of a star party in Florida. While there, he observed on February 19/20,
20/21, 21/22 and 23/24 for a total of 11.54 hours Teff (total effective
observing time). His tally during this period included 2 alpha Centaurids,
10 delta Leonids, 14 Virginids and 149 sporadics.
Not much meteor activity was expected for the month of March, and the number
of observers submitting reports reflected this. The four observers active
this month included John Drummond, New Zealand (March 2/3; Teff=1.00; 3
gamma Normids, 7 sporadics); Robert Lunsford, USA (March 20/21 and 26/27;
Teff=5.62; 2 gamma Normids, 8 Virginids, 42 sporadics); Francisco Ocana,
Spain (March 30/31; Teff=1.00; 1 sporadic). Harry Waldron, in a continuation
of his poor weather conditions in Virginia, sent a negative report. Toward
the end of March, NAMN member and comet chaser Mike Boschat of Canada
discovered his 28th SOHO comet. This placed both him and Canada in second
place in a ranking of former and present members of the SOHO LASCO Team.
With the arrival of April, NAMN issued an observing call for the Lyrids as
the conditions for this shower were optimal for observing. Twenty-eight
observers responded by sending in reports directly to the coordinator and/or
to the NAMN mailing list. These reports included:
April 9/10: Francisco Ocana, Spain (Teff=1.00; 1 sporadic)
April 17/18: Mark Davis, USA (Teff=2.00; 1 Lyrid, 8 sporadics)
April 18/19: Mark Davis, USA (Teff=1.00; 2 Lyrids, 4 sporadics); Pierre
Martin, Canada (Teff=2.46; 2 Lyrids, 1 mu Virginid, 4 Sagittarids, 12
sporadics)
April 19/20: Mark Davis, USA (Teff=1.00; 2 Lyrids, 5 sporadics); Pierre
Martin, Canada (Teff=1.45; 2 Lyrids, 7 Sagittarids, 2 sporadics)
April 20/21: Alejandra Leon Castella, Costa Rica (Teff=0.50; 4 Lyrids, 3
sporadics); Songqing Gao, China (Teff=4.50; 23 Lyrids, 10 sporadics); Nick
Martin, Scotland (Teff=1.45; 2 Lyrids, 2 sporadics)
April 21/22: Rainer Arlt, Germany (Teff=6.46; 61 Lyrids, 1 Sagittarid, 33
sporadics); Mark Davis, USA (Teff=4.25; 16 Lyrids, 13 sporadics); Yuwei Fan,
China (Teff=1.83; 17 Lyrids, 6 sporadics); Robert Gardner, USA (Teff=1.00; 1
Lyrid, 2 sporadics); George Gliba, USA (Teff=2.00; 18 Lyrids, 2 Sagittarids,
8 sporadics); David Hostetter, USA (Teff=1.76; 5 Lyrids, 3 sporadics); Terry
Johnson, USA (Teff=1.50; 1 Lyrid, 3 sporadics); Marco Langbroek, Netherlands
(Teff=2.47; 27 Lyrids, 5 mu Virginids, 25 sporadics); Mike Linnolt, USA
(Teff=1.00; 3 Lyrids, 2 Sagittarids, 8 sporadics); Robert Lunsford, USA
(Teff=1.00; 4 Lyrids, 3 sporadics); Norman McLeod, USA (Teff=1.67; 1 eta
Aquarid, 7 Lyrids, 7 sporadics); Huan Meng, China (Teff=1.50; 17 Lyrids, 3
sporadics); Koen Miskotte, Netherlands (Teff=5.97; 1 alpha Bootid, 61
Lyrids, 3 mu Virginids, 2 Virginids, 47 sporadics); Wanfang Song, China
(Teff=1.42; 10 Lyrids, 3 sporadics); Huiming Sun, China (Teff=3.27; 11
Lyrids, 9 sporadics); Richard Taibi, USA (Teff=2.75; 4 Lyrids, 3 sporadics);
Arnold Tukkers, Netherlands (Teff=4.83; 21 Lyrids, 2 Virginids, 56
sporadics); Shuo Wang, China (Teff=1.00; 5 Lyrids, 1 sporadic); Jin Zhu,
China (Teff=1.25; 7 Lyrids, 7 sporadics)
April 22/23: Cathy Hall, Canada (Teff=2.05; 4 Lyrids, 1 Sagittarid, 3
sporadics)
April 23/24: Jin Zhu, China (Teff=1.15; 2 Lyrids, 13 sporadics)
April 24/25: Robert Lunsford, USA (Teff=5.80; 2 eta Aquarids, 1 Lyrid, 7
Sagittarids, 18 sporadics)
April 26/27: Jure Atanackov, Slovenia (Teff=2.20; 16 sporadics)
April 29/30: Javor Kac, Slovenia (Teff=2.80; 1 eta Aquarid, 2 Sagittarids,
33 sporadics); Jure Zakrajsek, Slovenia (Teff=2.08; 18 sporadics)
Negative reports were received from Amir Hasanzadeh, Iran; Soheil
Khoshbinfar, Iran; Ed Majden, Canada; Hamid Rahkoi; Iran; Fred Weber, USA;
Kim Youmans, USA.
Our thanks go to all of these observers whose reports are mentioned above!!
4. Elmo Does Meteors - How to Interest Kids...
In late April, the Ottawa Valley Astronomy and Observers Group put on a 16
hour International Astronomy Day celebration in a parking lot outside a
large bookstore in Ottawa, Canada. It was a great opportunity to reach out
to the public and tell them about meteor observing! Co-author Cathy Hall was
able to attend and help out with this great outreach effort.
During the 16 hours of the event, over 1,000 people of all ages stopped by
to chat and ask questions about our astronomical displays. We had about a
dozen
telescopes, ranging in size from a 16-inch Newtonian reflector on a
Dobsonian mount down to a beginner size refractor. We had a high tech
computer controlled 12-inch Meade LX200 with a television monitor display
showing the spots on the sun by day and moon craters by night. We had
binoculars on special manipulative binocular mounts. We had a full size
wooden take-down portable observatory with Schmidt-Cassegrain telescope
inside. And - we had Pierre Martin's rather unique meteor coffin, complete
with meteor observing dummy - bright red Elmo of Sesame Street fame!
Elmo was all snug and comfortable in Pierre's mummy shaped sleeping bag, on
top of a reclining Coleman camp cot. Surrounding the camp cot was Pierre's
portable "coffin" a series of lightweight wooden panels hinged together to
form 4 walls, with the wall at the head end higher to block light trespass
near the observer. Under actual observing conditions, Elmo would have a
lightweight silver survival tarp fastened over the wooden walls to help
keep heat inside on cold nights, and perhaps have a portable heater. Behind
Elmo, we placed a blue umbrella with white stars and constellations, to
mimic the night sky. Pierre placed a small tape recorder inside the
sleeping bag, and set it to play an actual night of recorded meteors -
Leonids no less. This lady Canadian co-author, Pierre, and (yes) Elmo all
traveled to Europe for the Leonids in 1999. Elmo had a plotting map on his
little lap, and an inflatable space shuttle was just off to his side - you
can see the space shuttle go over when you are watching meteors too!
The kids loved him! They saw the sun and moon through all the fancy
telescopes, with all the wires and power packs and fancy computer
controlled drives - and they saw that you don't need any of that to watch
meteors like Elmo. All you need is a lawnchair and a sleeping bag. We had
so many cries of glee from the kids - "look Daddy, it's Elmo!"
We had information for older viewers too. Our brochures on NAMN, the North
American Meteor Network, were popular. They provide information on the how,
why, when and where of meteor observing, a list of showers for 2001, and
who to contact for more information. They are available for public events,
star parties and astronomy clubs - send a note to our NAMN coordinator if
you would like to get one to run off some copies for your particular event!
We had photos of meteors and fireballs interspersed with shots of galaxies
and star clusters on our display panels. Oh, and comets too, of course,
being the usual parent bodies of our meteor streams. This Canadian
co-author made sure to wear a colorful astro shirt with shooting stars both
back and front. We had a helium filled metallic comet. We did have a helium
filled metallic sun too, but it flew out of orbit, and the last we saw, it
was headed south towards the U.S. border. We had assorted astronomical
rubber stamps that the kids could use to make inked impressions on paper -
and we also had astronomical pictures that they could take home to color.
Courtesy of Sky and Telescope magazine, we had hundreds of free handout
booklets on "Getting Started in Astronomy." These include star charts and a
moon map, and are available free of charge to astronomical groups doing
displays for the public. Thank you, Sky Publishing!
The OAOG, the Ottawa Valley Astronomy and Observers Group, was co-founded
by Rock Mallin of Ottawa back in 1994, and has become an enthusiastic
addition to the Canadian amateur astronomical community. Their website can
be found at http://members.homedot net/observers-group.
Thanks to the OAOG for a great day, and a wonderful opportunity to help
spread the word about meteor observing to the public!
5. Upcoming Meetings...
June 30 - July 5, 2001 - Russia:
The Tunguska 2001 International Conference will be held in Moscow from June
30 to July 1st, followed by a special trip from July 2nd to 5th to visit
the epicenter of the famous Tunguska event of 1908. For information,
contact Andrei Ol'khovatov at olkhov@mail.ru and check out the website info
at http://www.geocities.com/olkhov/conf01.htm.
August 6-10, 2001 - Sweden:
The Meteoroids 2001 conference will be held at the Swedish Institute of
Space Physics in Kiruna, Sweden. Topics covered will include historical
observations and perspectives on meteoroids; dynamics, sources and
spatial distribution; detection and characteristics of meteoroids from
interstellar space; the meteoroid interaction process in the atmosphere;
hypervelocity impact effects on spacecraft; Leonid meteor storms;
optical observations of meteors; and meteor radar work. For
information, contact Asta Pellinen-Wannberg at
asta.pellinen-wannberg@irf.se and check out the website at
http://www.irf.se/Meteoroids2001.
September 20-23, 2001 - Slovenia:
IMC 2001, the worldwide meeting for meteor observers of the
International Meteor Organization, will be held this year in the town of
Cerkno, in Slovenia. This is a convention for both amateurs and
professionals. For North Americans not familiar with the map, Slovenia
is on the Adriatic Sea, east of Venice and south of Austria. It is
within driving distance of major European cities. This is a great
opportunity to meet and chat with observers from all over the globe -
and a wonderful excuse to visit Europe as well! Come join us! The
early registration deadline, for reduced registration rates, is July
1st. Details can be found on the IMO website at http://www.imodot net.
6. For more info...
Contact:
Mark Davis, MeteorObs@charlestondot net
Goose Creek, South Carolina, USA
Coordinator, North American Meteor Network
And check out:
NAMN home page:
http://web.infoavedot net/~meteorobs
Back issues of NAMN Notes can be found on-line at the NAMN website, and
in the meteorobs archives at:
http://www.tiacdot net/users/lewkaren/meteorobs
by selecting 'Browse Archive by Month'
To subscribe to the meteor email list or
To find out information on our weekly chat sessions:
Contact Lew Gramer at:
dedalus@alum.mitdot edu
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Here's to 'Clear Skies' for May...
May 2001 NAMN Notes co-written
by Mark Davis and Cathy Hall
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