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. February Meteor Activity...
2. Winter Comets to Check Out...
3. Upcoming Meetings...
4. For more info...
There are a number of interesting meteor showers in February to keep observers outside and alert, if they are willing to brave the winter weather and take in some of the delightful winter skies!
Although not on the official IMO, International Meteor Organization, 'Working List of Visual Meteor Showers', a watch should be kept for any possible xi Bootids. These were first seen by observer George Gliba from February 5/6 to 8/9 in 1997 from the Florida Keys. These were noted as medium velocity meteors, with an average magnitude of about 3.6 and a radiant near the star xi Bootes. Xi Bootis is about 8 degrees to the left of the star Arcturus on a star map.
The alpha Centaurids (ACE) reach a maximum on February 7th, with a radiant at 210 degrees, ie. RA 14h 00m, Dec -59, which is roughly 50 degrees south of the bright star Spica in the constellation of Virgo. These meteors can be seen from about January 28th until February 21st. These are average velocity meteors, at about 56 km per second. ZHR rates at maximum will be about 6 meteors per hour. A map showing the movement of the radiant can be found at http://www.imo.net/calendar/cal05.html#alpha-Centaurids. This is primarily a southern hemisphere shower - but one which can produce fireballs and outbursts. In 1974 and 1980, outbursts of 20-30 meteors per hour were seen for several hours. The predicted maximum on the 7th is at 22h 45m UT, Universal Time.
What is ZHR? ZHR refers to Zenithal Hourly Rate, and is the number of meteors that an observer would expect to see in an hour, on average, if they are observing under a dark country sky with no moon, and if the radiant, the area in the sky where the meteors seem to come from, is directly overhead at the 'zenith'.
The delta Leonids (DLE) peak on February 24th, and can be seen from about February 15th until March 10th. At maximum, the radiant will be at 168 degrees, ie. RA 11h 12m, Dec +16, which is very near the star theta Leonis, the lower right star in the triangle at the end of Leo. These are slow meteors, with a velocity of about 23 km per second. ZHR rates at maximum will be about 2 meteors per hour - but they will be quite distinctive. A map showing the movement of the radiant can be found at http://www.imo.net/calendar/cal04.html#delta-Leonids.
The gamma Normids (GNO) start to become active about February 25th, although won't reach a maximum until about March 13th. These are fast meteors, with a velocity of about 56 km per second. ZHR rates at maximum will be about 8 meteors per hour, but rates in February will be lower. With a radiant about 30 degrees south of the top of the 'J' of Scorpius, this is primarily a southern shower. A map showing the radiant can be found at http://www.imo.net/calendar/cal05.html#gamma-Normids
The Virginids (VIR) started to become active about January 25th, and last until about April 15th. These are almost slow meteors, at about 30 km per second. ZHR rates are about 5 meteors per hour. On January 30th, the radiant was at 157 degrees, ie. RA 10h 28.2m, Dec +16, which was about 6 degrees up to the left of Regulus in Leo on a star atlas. The radiant moves throughout the month of February - positions at intervals are as follows:
Feb. 10 165 +10 ie. RA 11h 00m Dec +10 Feb. 20 172 +6 ie. RA 11h 28.2m Dec +6 Feb. 28 178 +3 ie. RA 11h 52.2m Dec +3
These positions are from the IMO 2005 Meteor Shower Calendar. The calendar is very useful - print yourself off a copy from http://www.imo.net/calendar/cal05.html
If you want to record data on these showers 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. For estimating the brightness of the meteors you see, we have a handy set of 4 star charts (set printer to 'landscape mode') at http://www.namnmeteors.org/charts.html. If you have any questions, drop a note to our NAMN Coordinator at meteors@comcast.net
Forms to record your observations can be found at
http://www.namnmeteors.org/namn_form.html and
http://www.namnmeteors.org/appendixC.html.
Besides February's main activity, and other minor showers, there is also sporadic meteor activity - about 7 meteors per hour, visible to the unaided eye. Some of these are random, and some belong to old untraceable meteor showers.
For information on daytime meteor showers, mainly of interest to radio observers, check out the IMO website at http://www.imo.net. The Cap/Sagittarids peak on February 1st, and the chi-Capricornids on February 13th.
Planets at midmonth, and their magnitudes, for northern observers, are:
Jupiter -2.2 in Virgo Saturn -0.2 in Gemini Mars 1.3 in Sagittarius, low in southeast in morning sky
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'.
This month, the phases of the moon are as follows:
Wed. Feb. 2 last quarter Tues. Feb. 8 new moon Wed. Feb. 16 first quarter Thurs. Feb. 24 full moon
For a great printout of moon phases for the month, check out http://stardate.org/nightsky/moon
Comet Machholz, discovered by comet hunter Don Machholz of the United States on August 27th, is still a nice sight in our winter skies. Get out and enjoy it!
Coordinates and brightness estimates for February are as follows, courtesy of the Sky and Telescope website at http://skyandtelescope.com:
Feb. 4 RA 2h 52m Dec +65 41 Cassiopeia mag. 4.9 Feb. 9 RA 2h 51m Dec +70 05 Cassiopeia mag. 5.2 Feb. 19 RA 3h 05m Dec +77 10 Cassiopeia mag. 5.7 Mar. 1 RA 4h 07m Dec +82 29 Cepheus mag. 6.2
To check out other comets visible in our winter skies with amateur sized telescopes, the following websites are extremely useful:
Greg Crinklaw's 'Skyhound':
(good printable finder charts)
http://www.skyhound.com/sh/skyhound.html
Seiichi Yoshida's 'Weekly Information about Bright Comets':
(with excellent previews of future positions)
http://www.aerith.net/comet/weekly/current.html
Comet Section of the B.A.A., British Astronomical Association:
(excellent information and links)
http://www.ast.cam.ac.uk/~jds/
August 7-12, 2005, Brazil...
ACM 2005, the IAU Symposium 229: Asteroids, Comets, Meteors, will be held
in Rio de Janeiro, Brazil. The main topics of the conference will be space
missions, internal structure of asteroids and comets, connections between
asteroids, cometary nuclei and Trans-Neptunian Objects (TNO's), connections
between asteroids and meteorites, connections between comets, meteor showers
and interplanetary dust, minor body dynamics, collisions and impacts,
Near-Earth Objects (NEO's), origin and evolution of our Solar System and
extra-solar planetary systems. The website for the conference is at
http://www.on.br/acm2005. For more information, contact Daniela Lazzaro or Fernando Roig at acm2005@on.br
September 15-18, 2005, Belgium...
The 2005 IMC, International Meteor Conference of the IMO, the International
Meteor Organization, will be held in Oostmalle, Belgium. Oostmalle is about
70 km north of Brussels, and about 30 km northeast of Antwerp. The
conference is being organized by Urania, the public observatory of Antwerp.
Accommodation will be at the Provinciaal Vormingscentrum Malle, with an
excursion to the city of Lier. This is a great opportunity to meet and
chat with meteor observers from all around the globe - so mark it on your
calendar now, and plan to attend! The participation fee is 120 EUR, and
includes all accommodation, all meals, and the conference registration. For
information, check out the conference website at http://www.imo.net/imc2005.
For questions, contact Jan Verbert at imc2005@imo.net
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
Metcalfe, Ontario, Canada
Writer, NAMN Notes
Lew Gramer, dedalus@alum.mit.edu
Medford, Massachusetts, 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