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(meteorobs) Call for Observations, 2001 January 20-26: The January Coma Berenicids
Call for Observations, 2001 January 20-26: The January Coma Berenicids
By Roberto Gorelli and Alastair McBeath
We have recently identified a possible new minor shower, with a radiant
perhaps only periodically active between January 20-26 or so, in Coma
Berenices or a neighbouring constellation. This shower may be associated
with the poorly-observed Comet Lowe 1913 I, seen definitely and briefly
at only a single return, but which may also have been observed, again
rather badly, in 1750. The computed shower parameters suggest a radiant
near alpha = 188 degrees, delta = +22 degrees, producing its maximum
activity around January 24 (solar longitude = 304.2-305.0 degrees, eq.
J2000.0). The meteors would be swift-moving, with an atmospheric
velocity of 59 km/s, similar to the Perseids of July-August. Determining
more about this possible shower is important, since Comet Lowe may have
the potential to impact the Earth in the second half of the 21st
century.
We have provisionally called this source the January Coma Berenicids to
differentiate it from the "other" Coma Berenicids active from about
December 12-January 23, peaking towards December 20, as we suspect the
two are actually separate showers, though this is uncertain as yet. Some
visual and radio January Coma Berenicid activity seems present in the
reports we have checked, but not necessarily in every year. A radio peak
coinciding in time with several visual fireballs (the source of these is
unknown however) occurred on 1998 January 24-25, for instance, while two
Slovenian observers reported a small visual outburst perhaps from near
Corona Borealis on 1999 January 21-22. A further possible outburst may
have occurred on 2000 January 20-21, noted by a single UK witness (this
possible radiant may have been north-west of Ursa Major though, not
south-east of it). The 1999 and 2000 events may both have been weakly
present in the radio results too.
As new Moon falls on January 24, conditions are perfect for checking in
2001, and we would urge all observers who can to watch for whatever
happens. Although January 23-24 and 24-25 are probably the most
important dates to cover, other dates between January 20-26 should not
be ignored if the sky is clear. Standard IMO visual plotting watches
should be carried out as normal at this time of year, and any possible
January Coma Berenicids identified as such after the observation,
assuming an unusual level of activity is not apparent in the field.
Ideally, video or photographic techniques should be employed too, since
we need to establish the presence of any radiant(s) and the orbital
parameters for any meteors connected to this source. From northern
hemisphere sites, the proposed radiant is well on-view from about
22h30m-23h local time, culminating shortly before dawn. Circumstances
are less favourable well south of the equator, where the radiant can be
clearly observed only after 01h30m-02h local time. All data, even
negative results (that is, where observations were made with clear
skies, but no possible January Coma Berenicids were seen), would be
useful, remembering we know almost nothing about this possible shower.
We would also like anyone with data on meteor activity from this part of
January from before Comet Lowe's discovery onwards to let us know if any
possible radiant is indicated around the Coma to Corona region,
especially where any orbital characteristics for the meteors could be
established. In addition we would urge anyone with access to the
appropriate information to check for prediscovery images of Comet Lowe
taken in the Virgo region in December 1912.
All reports should be submitted to the appropriate IMO Commissions as
normal, but the present authors would be pleased to receive copies of
any data from the January 20-26 period separately too, for rapid
analysis. This applies both to 2001 results and any from previous years.
Further information on the possible January Coma Berenicids can be found
in our article in the December 2000 issue of the IMO's journal "WGN".
Further to our acknowledgements there, we are grateful to David Asher
and Mark Bailey of Armagh Observatory for forwarding the 2000 January
20-21 report to us, noted above. This, with the Slovenian observations,
decided us to extend the investigated period beyond the dates originally
suggested in our "WGN" article.
Good luck, and clear skies!
E-mail addresses:
Roberto Gorelli: <md6648@mclinkdot it>
Alastair McBeath: <vice_president@imodot net>
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