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. Eta Aquarids - Debris from Halley's Comet...
2. Other May Showers...
3. International Astronomy Day...
4. Comet Flyby of Schwassmann-Wachmann 3...
5. Upcoming Meetings...
6. For more info...
The highlight of the month of May is the eta Aquarid meteor shower. This meteor shower is of particular note as it originates with the rather well known comet of... Edmond Halley.
It is wonderful to think as we observe these meteors that we are seeing pieces of debris from the famous Halley's Comet. But wait - did Halley really discover this comet? Surprisingly, no. Halley became famous for realizing that the comets of 1531, 1607 and 1682 were all one and the same comet. He found this out by comparing the information about their orbits. It was this significant discovery that resulted in these comets being renamed... Comet Halley.
Halley contributed a great deal to science - and in many ways that most people are not aware of. In the field of astronomy, he compiled the first systematic catalogue of stars in the southern hemisphere. He was the first to recognize that stars move in relation to one another. He noted that observing transits of Venus passing in front of the sun would make it possible to calculate the distance from the sun to the earth. He became Astronomer Royal in Great Britain in 1720, and held the post for 21 years, until shortly before his death at Greenwich in his late 80's.
In fields other than astronomy, Halley was also well known. He designed an underwater diving bell. He published the very first meteorological map, showing prevailing winds over the oceans. He produced one of the earliest studies of human mortality, which was quite influential in the actuarial industry. He was a naval captain of a ship called the Paramore Pink, and sailed all over the Atlantic Ocean charting the variation of the earth's magnetic field. He persuaded Newton to publish the Principia Mathematica, and paid for the publishing costs out of his own pocket.
The eta Aquarid (ETA) meteor shower reaches a maximum on May 6th this year at about 6h UT, although the meteors can be observed from about April 19th until May 28th. These are fast meteors, with a velocity of about 66 km per second.
The radiant at maximum is at 338 degrees, ie RA 22h 31.8m, Dec -01, which is very near the star eta Aquarius on a star atlas. The radiant is the area in the sky that the meteors seem to come from. The radiant does move over time though - check out the map on the website of the International Meteor Organization (IMO) at http://www.imo.net/calendar/2005/spring
Aquarius, the 'water-bearer' is an interesting constellation in the sky - and a constellation that you should learn well now, before all the other Aquarid meteor showers become active later in the summer. It is a constellation that is best seen under fairly dark skies, as many of its stars are not that bright. The darker your sky is, the more easily recognizable the constellation outline will become.
In ancient Greek myth, Aquarius was the cup bearer of Zeus - and a male. The story goes that the original cup bearer was a woman - Hebe, goddess of youth, and a daughter of Zeus and Hera. On Olympus, she served the gods nectar and attended to Hera's chariot. One version says that Hebe slipped and sprained her ankle, and couldn't serve as cup bearer that day. Another version of the story is that Hercules came to live at Olympus and Hebe was given to him in marriage, and relieved of her cup bearing duties.
At any rate, Zeus went looking for another cup bearer, and spotted a handsome shepherd boy in the mountains near Troy. Some versions say a Trojan prince. Whatever his stature, his name was Ganymede. Zeus decided to make Ganymede his cup bearer instead. Zeus changed himself into an eagle and carried Ganymede off to Olympus. Hence, we have Ganymede as the cup bearer Aquarius in the sky and the eagle as the nearby constellation Aquila. The constellation Aquarius traditionally represents the bringer of water, not wine - and spring floods - in many cultures.
For the eta Aquarid meteors radiating from this interesting constellation, ZHR rates at the peak will be about 50-60 meteors per hour, although are periodically variable. ZHR refers to Zenithal Hourly Rate, the number of meteors, on average, that an observer would expect to see per hour if they are out under a dark country sky, and if the radiant, the area in the sky where the meteors seem to come from, is directly overhead at the 'zenith'.
According to the IMO, in their 2006 Meteor Shower Calendar:
"A fine, rich stream associated with Comet 1P/Halley, like the Orionids of October, but one visible for only a few hours before dawn... The fast and often bright meteors make the wait for radiant-rise worthwhile, and many events leave glowing persistent trains after them. While the radiant is still low, eta-Aquarids tend to have very long paths... "
"A relatively broad maximum, sometimes with a variable number of submaxima, usually occurs in early May... IMO analyses in recent years... have shown that ZHRs are generally above 30 between about May 3-10, and that the peak rates appear to be variable on a roughly 12-year timescale. The next highest rates should fall towards 2008-2010, if this Jupiter-influenced cycle is borne-out. Thus visual ZHRs should be around 50-60 in 2006, according to this idea... "
If you want to record visual data for the meteor researchers, check out our NAMN Observing Guide for information on what to record. Our Guide can be found at http://www.namnmeteors.org/guide.html. We record such info as the time a meteor occurred, its magnitude (brightness), the shower it belongs to, its speed, and other comments such as train left behind, or color. General information to record includes such things as how dark your perceived sky is (limiting magnitude), and comments on weather and cloud cover. If you have any questions, drop a note to our NAMN Coordinator at meteors@comcast.net
NAMN has some good star charts to mark your radiants on before you go out observing. These charts also show constellations for the whole sky, and give the brightness of a number of stars to use in judging the magnitude of the meteors you see. Our 4 printable charts can be found at http://www.namnmeteors.org/charts.html. Set your printer to 'landscape' mode.
Forms to record your observations can be found at http://www.namnmeteors.org/namn_form.html and http://www.namnmeteors.org/appendixC.html
The opportunity to see debris from Halley's Comet is something very special! Make the effort to head outside in the wee morning hours to enjoy this wonderful meteor shower!
The Sagittarids (SAG) started to become active about April 15th and will last through until about July 15th. These are almost slow meteors at about 30 km per second. ZHR rates are about 5 meteors per hour. Coordinates for the radiant in May are as follows:
May 05 236 -20 ie. RA 15h 43.8m Dec -20 May 10 240 -21 ie. RA 16h 00.0m Dec -21 May 20 247 -22 ie. RA 16h 28.2m Dec -22 May 30 256 -23 ie. RA 17h 04.2m Dec -23
For observers interested in radio meteor showers, we have the following peak dates:
epsilon-Arietids May 9 13h UT May Arietids May 16 14h UT o-Cetids May 20 13h UT
For full details on these showers and details on other radio showers that start in May but do not peak until June, check out the IMO website at http://www.imo.net
For other minor showers not on the International Meteor Organization's, 'Working List of Visual Meteor Showers', and for a wealth of historical information on all showers, check out Gary Kronk's 'Comets and Meteor Showers' website at http://comets.amsmeteors.org
Besides May's main activity and other minor showers, there is also sporadic meteor activity. This sporadic meteor activity is about 7 meteors per hour, visible to the unaided eye. Some of these are random and some belong to old untraceable meteor showers.
Planets at midmonth, and their magnitudes, for northern observers, are:
Venus -3.9 very low in east in morning twilight Jupiter -2.5 in Libra Saturn 0.3 in Cancer, low in west in evening twilight Mars 1.6 in Gemini
For a sky chart showing the positions of all the planets visible this month, go to http://www.heavens-above.com, select your country, then your city, and go to 'Whole Sky Chart'.
The phases of the moon for May are as follows:
Fri. May 5 first quarter Sat. May 13 full moon Sat. May 20 last quarter Sat. May 27 new moon
For a great printout of moon phases for the month, check out http://stardate.org/nightsky/moon
This year International Astronomy Day is being celebrated on Saturday, May 6th, with Astronomy Week running from May 1st to 7th.
What is Astronomy Day? Quoting from the Sky and Telescope website at http://skyandtelescope.com:
"Doug Berger, former president of the Astronomical Association of Northern California, founded this annual event in 1973 as a high-profile way of drawing public attention to the science and the hobby through exhibits and activities at urban centers... Hundreds of astronomy clubs, observatories, museums, colleges, and planetariums worldwide now host special family-oriented Astronomy Day events and festivities."
Groups and individuals all around the world will be using this opportunity to help spread the word about astronomy. The official Astronomy Day webpage is hosted by the Astronomical League at http://www.astroleague.org/al/astroday/astroday.html
Meteor observers can also help out. Here are some suggestions:
- offer to help out with your local astronomy club's activities, and take along some copies of our NAMN handout sheets for the public
- offer to give a short talk on meteors or meteorites to a local school class or scout group
- contact a local library or bookstore, and offer to help them set up a special display of astronomical books for Astronomy Day
- if you are not available in person for Astronomy Day, offer some of our NAMN handout material to a group that is putting on a display for the public
NAMN has the following handout material that we can email you to print off:
1. "How to Observe Shooting Stars" - our tri-fold, 2-sided NAMN brochure 2. "What are Meteors?" - a 1 page info sheet on showers throughout the year 3. "What is a Meteor?" - a French info sheet, with thanks to Pierre Martin 4. "Surf the Astro Web!" - a list of recommended astronomy websites 5. "What's Up Tonight?" - how to find out what's visible in tonight's sky
These resource sheets are available in electronic form at no charge - just email Lew Gramer, our Public Outreach Coordinator at dedalus@alum.mit.edu, or any of the rest of us, addresses at the end of the newsletter. The handout material is all in Word format, and you can print off as many copies as you need.
Heavens-Above, the website that brings you information on satellites and the times you can see the International Space Station (ISS) go over your home, has some great printable star maps. These can be found at http://www.heavens-above.com. Ignore the 'Register' bit. Go to 'Select' your location, then pick your country, and city. Then go down the page to 'Whole Sky Chart'. Pick a night and time, change to 'black on white', and print yourself off a batch of star charts to hand out to the public.
The International Dark Sky Association has great handout sheets on how to use better lighting for your home - and preserve the Milky Way for your kids. A good printout for Astronomy Day is "Light Pollution: The Problem, The Solutions" by D.L. Crawford at http://www.darksky.org/infoshts/is134.html
International Astronomy Day is a great opportunity to help spread the word about astronomy, and about meteor observing... and about just getting outside at night to appreciate our wonderful night sky!
Back on March 24th, NASA posted a news release to its website at http://science.nasa.gov/headlines/y2006/24mar_73p.htm regarding the breakup of Comet Schwassmann-Wachmann 3.
More news has been coming in as it happens. Stay tuned to the NASA headlines at http://science.nasa.gov and news on the Sky and Telescope website at http://skyandtelescope.com
Comet 73P/Schwassmann-Wachmann 3 was discovered on April 27, 1930 by A. Schwassmann and A.A. Wachmann of the Hamburg Observatory in Germany - and broke apart in 1995. The pieces have been undergoing further fragmentation, and are due to fly past the earth from about May 12th to 14th.
What we will see by then is not exactly known. The comet continues to break up day by day. As of mid-April, there were about 40 fragments, according to an article in Sky and Telescope. However, many of the fragments are very faint, and not easily seen by amateur telescopes. Stayed tuned to the web news to hear what is happening - and what we will be able to see as the time for the flyby approaches.
The best detailed finder charts for the comet can be found at:
Kometarium by Burkhard Leitner:
http://www.kometarium.com
Astrosite Groningen by Reinder Bouma and Edwin van Dijk:
http://www.shopplaza.nl/astro/
Skyhound by Greg Crinklaw (includes a special page just for this comet):
http://www.skyhound.com/sh/skyhound.html
There is also speculation on a possible associated meteor shower. Its timing and strength will be dependent on what caused the breakup. For ongoing details on this possibility, we suggest you subscribe (if you haven't already) to our MeteorObs email list. Contact Lew Gramer at dedalus@alum.mit.edu for details. You can subscribe - and unsubscribe - from the list at any time.
May 12-14, 2006, Vienna, Austria...
MACE 2006, the Meeting on Asteroids and Comets in Europe, will be held in
Vienna, Austria at the historic Kuffner Observatory. The scientific program
will be divided into 4 sessions - astrometry and celestial mechanics, the
physical study of asteroids and comets, instrumentation and techniques, and
workshops and hands-on practice. Excursions include visits to the Vienna
University Observatory, where Johann Palisa used the (then) largest
refractor in the world to discover asteroids, and to the famous meteorite
collection of the Natural History Museum, the largest of its kind in the
world. And - this is Mozart Year in Austria! For details, check out the
conference website at http://www.astrometrica.at/MACE
June 8-14, 2006, Ostersund, Sweden...
The Workshop on Impact Craters as Indicators for Planetary Environmental
Evolution and Astrobiology will be held in Ostersund, Sweden. Sessions
include terrestrial craters, craters on other planetary bodies, the
influences of the impact on the target area, the target area on the fate of
the projectile, and the properties of the impactor on the cratering process,
other consequences (eg. tsunamis), environments created by the impact and
their importance for life, and astrobiological aspects of impact cratering.
There will be two study field trips to the Lockne Crater, and an excursion
to the GeoCenter-Lockne Impact Crater Museum. For information, check out
the website at
http://www.geo.su.se/Lockne2006 and contact Dr. Jens Ormo of
the Planetary Geology Laboratory, CSIC/INTA, Madrid, Spain at ormo@inta.es
July 10-14, 2006, Singapore...
The AOGS, Asia Oceania Geosciences Society, will hold its 3rd Annual Meeting
in Singapore. Jeremie Vaubaillon has advised us that there will be a
special session on the field of meteor science. Topics covered at the
conference are quite varied - invited speakers include G. Consolmagno of the
Vatican Observatory on 'Evidence from Meteorites', Cheng Fang of Nanjing
University on 'Spectroscopic Approaches to Solar Flares: A Review', Paul
Jones of the Australia Telescope National Facility on 'Radio Observations
from Australia of Comet 9P/Tempel 1 for Deep Impact', and Dave Anderson of
NOAA on 'Solar Activity and Indian Monsoons'. The deadline for abstract
submission is February 15th. The deadline for reduced fees for registration
is May 15th. For information, check out the website at
http://www.asiaoceania-conference.org and contact
info@asiaoceania-conference.org
September 14-17, 2006, Roden, The Netherlands...
The IMC, the International Meteor Conference of the International
Meteor Organization, will be held near Roden in the Netherlands. This is
the annual get-together for both amateur meteor observers and professional
researchers alike. Talks will cover all types of meteor observing - visual,
telescopic, photographic, video, and radio. The registration fee is 120
Euros, and includes the conference, all meals, all accommodation, an
excursion, and a conference t-shirt. Special workshops will be held on
meteor orbit determination and radio meteors from September 11th to 13th,
with a separate fee. Mark Holland on your calendar for September! For more
info, check out http://www.imo.net/imc2006
For information on upcoming astronomy meetings, see: "International Astronomy Meetings List" at http://cadcwww.hia.nrc.ca/meetings
NAMN email: namn@namnmeteors.org
NAMN website: http://www.namnmeteors.org
Mark Davis, meteors@comcast.net
Goose Creek, South Carolina, USA
Coordinator, North American Meteor Network
Cathy Hall, chall@cyberus.ca
Ottawa, Ontario, Canada
Writer, NAMN Notes
Lew Gramer, dedalus@alum.mit.edu
Homestead, Florida, USA
Coordinator, Public Outreach
Owner/Moderator, 'MeteorObs'
Kevin Kilkenny,
namnfireball@earthlink.net
Staten Island, New York, USA
Coordinator, Fireballs and Meteorites
Back issues of NAMN Notes can be found on-line at the NAMN website
and in the MeteorObs archives at:
http://www.meteorobs.org
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.mit.edu