[Prev][Next][Index][Thread]
(meteorobs) NAMN Notes: September 2003
**************************
NAMN Notes: September 2003
**************************
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
Contents:
1. The Alpha-Aurigids...
2. The Aries-Triangulid Meteors... by George Gliba
3. Other September Meteor Activity...
4. Pro-Am Cooperation for Comet Observers...
5. Upcoming Meetings...
6. For more info...
1. The Alpha-Aurigids...
Welcome to September! The blitz of summer meteors has now subsided, and
observers can now settle into a quieter month. This is a good time to
regroup and decide on some meteor projects for the coming fall season.
The alpha Aurigids (AUR) are a good project to start with! This shower
reaches maximum activity on September 1st at 12h UT, although activity can
be seen until about September 8th. These are fast meteors, with a velocity
of about 66 km per second. ZHR rates on the 1st will be about 7 meteors
per
hour. What is ZHR? It stands for Zenithal Hourly Rate, and is the number
of meteors that an observer could expect to see 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.
The alpha Aurigids are believed to be associated with Comet Kiess 1911 II.
This comet was discovered by C.C. Kiess of the Lick Observatory on a
photographic plate taken with the Crocker Photographic Telescope. It has
an
elliptical orbit with a period of about 2500 years.
The IMO, the International Meteor Organization, states that observers are
really needed for this shower! Outbursts occurred in 1935, 1986 and 1994.
According to the IMO Handbook: "The activity level of the alpha Aurigids
seems to vary from one year to the next, and can occasionally reach three
to
five times the... normal ZHR value". Please monitor this shower!
A map showing the radiant position can be found at
http://www.imodot net/calendar/cal03.html#alpha-Aurigids The radiant on the
1st will be at 084 degrees, ie. RA 5h 36m, Dec +42, which is about 5
degrees
to the left of the star eta Auriga, also known as Hoedus II, the
'Charioteer's 2nd kid goat'. Auriga is the Charioteer, and is depicted in
mythology as a herdsman holding a she-goat (the star Capella) and two kids.
For details on what to record, if you want to contribute useable data,
check
out our NAMN Observing Guide at http://www.namnmeteors.org/guide.html.
The information to record while observing is fairly basic... data for each
meteor, such as time it occurred, magnitude (brightness), shower it belongs
to, 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. Forms to
record your observations can be found at
http://www.namnmeteors.org/namn_form.html and
http://www.namnmeteors.org/appendixC.html. Any questions on what to
record,
or how, can be sent to our NAMN Coordinator at meteors@comcastdot net
For showers such as the alpha Aurigids, where we are really trying to study
them and learn more about them, plotting their paths on star maps is a very
good idea. We have special plotting maps we use, with a special projection
of the sky, such that meteors can be plotted as straight lines. Observers'
plotting maps are forwarded by NAMN to the IMO, the International Meteor
Organization, and the meteor plots are scanned into the IMO database, for
use by meteor researchers! You can get a set of these maps by dropping a
note to Robert Lunsford of the IMO at secretary@imodot net. There is a
nominal
cost for photocopying and mailing.
Good luck on the alpha Aurigids - and try to help us out by observing this
shower!
2. The Aries-Triangulid Meteors... by George Gliba
There might be some significant activity visible from the Aries-Triangulid
minor meteor shower (aka alpha Triangulids) expected this year, despite the
full moon on September 10th. The Aries-Triangulid maximum should be a
couple
nights later on September 12th or 13th, and the moon will greatly
interfere.
However, there is some historical evidence that this stream may be
periodic,
and that this year may be a more active one than usual. The primary radiant
appears to be near alpha Trianguli, with a secondary radiant located
further
south near the 2nd magnitude star Hamal (alpha Arietis).
Historically, this shower seems to have a period of 5 or 6 years, according
to NAMN member, and comet & meteor researcher Gary W. Kronk. The last
years
with good activity were recorded in 1998 and 1999. The other known years,
when two or more experienced meteor observers saw good activity visually,
were in 1934, 1940, 1951 and 1993. So, it is possible that enhanced
activity might be visible this year and/or in 2004. Some activity has been
reported every year since this meteor stream was first discovered to be
possibly annual, ten years ago this month, when it was found by three North
American meteor observers.
(More information on the background of this shower can be found at
http://comets.amsmeteors.org and questions on this activity can also be
directed to George Gliba at gliba@milkyway.gsfc.nasadot gov. Observation of
this shower is encouraged, and plotting is highly recommended so we can
learn more about this meteor activity - ed.)
3. Other September Meteor Activity...
The delta Aurigids (DAU) reach a maximum on September 9th this year, with
activity visible from about September 5th until October 10th. ZHR rates at
maximum will be about 6 meteors per hour. These are fast meteors, with a
velocity of about 64 km per second. See a map of the radiant at:
http://www.imodot net/calendar/cal03.html#alpha-Aurigids. The radiant on the
9th is at 060 degrees, ie. RA 4h 00m, Dec +47, which is about 3 degrees to
the left of the star delta Perseus. The parent body responsible for these
meteors is uncertain.
The Piscids (SPI) reach a maximum on September 20th, with activity visible
for the whole month of September. At maximum on the 20th, ZHR rates will
be
about 3 meteors per hour, with rates lower before and after. These are
nice, slow meteors at 26 km per second - so will be easy to pick out. A
map
showing where they will come from in the sky can be found at
http://www.imodot net/calendar/cal01.html#Piscids. The radiant on the 20th is
at 005 degrees, ie. RA 0h 19.8m, Dec -01, which is about 15 degrees south
of
gamma Pegasus, the bottom left star of the Great Square of Pegasus.
The Sextantids, a daytime meteor shower normally detected by radio
observers, could yield some visual meteors. According to the IMO,
the Sextantids are "a tricky visual shower... maximum expected
on September 27, 21h UT, but possibly occurring a day earlier. In 1999 a
strong return was detected at sol~186 degrees, equivalent to 2003 September
29. New Moon gives no extra problems for visual observers hoping to catch
some Sextantids in late September, though the radiant rises less than an
hour before dawn in either hemisphere." Radiant positions can be found in
the IMO 2003 Meteor Shower Calendar at
http://www.imodot net/calendar/cal03.html#Table7
For meteor observing, and especially for new observers, we recommend
printing yourself off a set of our 4 NAMN star charts at
http://www.namnmeteors.org/charts.html. You can use these charts to mark
your meteor shower radiants on - the areas in the sky where the meteors
seem
to come from. Set your printer to landscape mode. These charts also
provide a series of 'standard' stars with magnitudes marked, to use in
judging the brightness of the meteors you see. For new observers, this set
of 4 star charts is also a great tool for learning your constellations.
The
charts are simple, and easy to use!
Note that radiant positions for all showers can be found in the IMO's
2003 Meteor Shower Calendar, in Table 6, at
http://www.imodot net/calendar/cal03.html#Table6 Our NAMN charts are labelled
such that you can take the numbers in the table, and mark the positions
easily on our NAMN charts.
Are there any other meteor showers visible in September? Yes. The showers
listed here are the ones on the 2003 'Working List of Visual Meteor
Showers'
of the IMO, the International Meteor Organization. There are many other
minor showers that can be studied by more experienced observers, or
telescopic meteor observers, or radio meteor observers. Details on many of
these can be found on Gary Kronk's 'Comets and Meteor Showers' website at
http://comets.amsmeteors.org
Besides recognized main showers, and other minor showers, there is also
sporadic meteor activity in September. This sporadic activity is about 7
meteors per hour, visible to the unaided eye. This activity is comprised
partly of random meteors and partly of meteors that belong to long-ago, now
untraceable showers.
This month, the phases of the moon are as follows:
Wed. Sept. 03 first quarter
Wed. Sept. 10 full moon
Thurs. Sept. 18 last quarter
Fri. Sept. 26 new moon
Planets at midmonth, and their magnitudes, for northern observers, are:
Mars -2.7 in Aquarius
Saturn 0.2 in Gemini
Jupiter -1.7 in Leo, in morning twilight
The planets are very good 'standards' for estimating the magnitude of
bright
meteors. Mars is very close to the earth right now, and also an excellent
object in amateur telescopes. On August 27th, it was at its closest in
about 100,000 years. On September 1st, it will be at about magnitude -2.9.
By September 11th, it will have faded to about -2.7, and by September 21st
will be at -2.4. It is fading, and by the end of the year will only be
about magnitude 0. Get out now and take a look at it!
4. Pro-Am Cooperation for Comet Observers...
Interested in serious amateur observations of both comets and meteors?
Check out the following workshop: The ICQ and the Societe Astronomique de
France are organizing a special workshop for amateur comet observers,
sponsored by the Paris Observatory. The IWCA III, the Third International
Workshop on Cometary Astronomy, will be held at the Meudon and Paris
Observatories in Paris, France, from June 4th to 6th, 2004.
Although not directly related to meteor science, there are many observers
and researchers who study both meteors and comets - so this will be of
interest to you! The workshop announcement states that "its main objective
is to promote cometary observations among amateur astronomers and optimize
the benefit of these observations for the use by professional
astronomers...
it shall be an opportunity for amateurs to meet professionals and exchange
about their techniques".
Topics to be discussed include comet photometry (CCD, visual, light
pollution effects, reference catalogs) and outgassing rates, comet imaging
(photographic, CCD, filters, spectroscopy), comet astrometry, observation
of
trans-neptunians by amateurs, comet discovery and automatic sky surveys,
space missions to comets, and internet tools. All topics covered will be
from the perspective of how amateur comet observations can be used by the
professionals, with feedback from the professionals regarding
standardization and best use of amateur resources.
Information can be found at http://www2.iap.fr/saf/IWCAIII. The
contact for information is Nicholas Biver at nicolas.biver@obspm.fr. There
is some financial support available for participants from eastern Europe or
other countries with limited financial resources. The workshop has been
timed to coincide with the transit of Venus on June 8th, visible from
France. Note that there is a guaranteed reduced rate for accommodation if
the first night is paid for before September 20, 2003. See the webpage for
more details!
By the way, what comets are coming up for amateur observers? Seiichi
Yoshida has a wonderful website for observers, showing what comets are
going
to be visible in the evening, midnight and morning skies for the coming
months - and years! For the northern hemisphere, check out
http://www.aerithdot net/comet/future-n.html. For the southern hemisphere,
check out http://www.aerithdot net/comet/future-s.html. Yoshida's 'Weekly
Information About Bright Comets' can be found at
http://www.aerithdot net/comet/weekly/current.html
5. Upcoming Meetings...
September 18-21, Bollmannsruh, Germany...
The IMC, International Meteor Conference, of the IMO, the International
Meteor Organization, will be held in Bollmannsruh, Germany. This is the
annual world meeting for amateur meteor observers and professionals alike!
The location of the conference is a hostel near the town of Brandenburg,
about 40 km west of Berlin. It is situated in a rural area by a lake, and
facilities include accommodation in bungalows, a cafe and bar, a lecture
hall, an open air stage, and a place for a campfire and barbecue. The
special excursion during the conference will be to Berlin to the Museum for
Natural History, for a lecture on meteorites and viewing of the meteorite
collection. For more information, check out
http://aipsoe.aipdot de/~rend/2003imc.html and
http://www.imodot net/news/imc.html
or contact Ina Rendtel at treasurer@imodot net. IMC 2003 marks the 15th
anniversary of the IMO - so meteor observers from around the globe are all
invited for this special event!
June 4-6, 2004, Paris, France...
IWCA III, the Third International Workshop on Cometary Astronomy, will be
held at the Meudon and Paris Observatories in Paris, France.
The workshop announcement states that "its main objective is to promote
cometary observations among amateur astronomers and optimize the benefit of
these observations for the use by professional astronomers... it shall be
an opportunity for amateurs to meet professionals and exchange about their
techniques". Topics to be discussed include comet photometry, outgassing
rates, imaging with filters and spectroscopy, astrometry, observation of
trans-neptunians by amateurs, discovery and automatic sky surveys, space
missions to comets, and internet tools. Information can be found
at http://www2.iap.fr/saf/IWCAIII. The contact for information is
Nicholas Biver, nicolas.biver@obspm.fr. There is some financial support
available for participants from eastern Europe or other countries with
limited financial resources. The workshop has been timed to coincide with
the transit of Venus on June 8th, visible from France. See the website for
details on cost - there is a room discount if replying by September 20th.
For more information on upcoming astronomy meetings, see: "International
Astronomy Meetings List" at http://cadcwww.hia.nrcdot ca/meetings
6. For more info...
NAMN email: namn@atmob.org
NAMN website: http://www.namnmeteors.org
Mark Davis, meteors@comcastdot net
Goose Creek, South Carolina, USA
Coordinator, North American Meteor Network
Cathy Hall, chall@cyberusdot ca
Metcalfe, Ontario, Canada
Writer, NAMN Notes
Lew Gramer, dedalus@alum.mitdot edu
Medford, Massachusetts, USA
Coordinator, Public Outreach
Owner/Moderator, 'MeteorObs'
Kevin Kilkenny, namnfireball@earthlinkdot net
Staten Island, New York, USA
Coordinator, Fireballs and Meteorites
Back issues of NAMN Notes can be found online 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:
Contact Lew Gramer at: dedalus@alum.mitdot edu
==============================================
Here's to 'Clear Skies' for September...
September 2003 NAMN Notes
written by Cathy Hall & edited by Mark Davis
==============================================
The archive and Web site for our list is at http://www.meteorobs.org
To stop getting all email from the 'meteorobs' lists, use our Webform:
http://www.meteorobs.org/subscribe.html