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Re: (meteorobs) January Coma Berenicids and the Xi Bootids

Lew in response to Bob:
> By the way, my understanding is that these meteors are expected to be both
> sparse (very few per hour) and also predominantly fainter. Considering that
> and the fact that a radiant point is NOT well determined, I wonder if this
> would be a good target for Telescopic Meteor observers?

Indeed it would.  Thanks for the prod.  Work permitting I intend to get
a few hours in after midnight at at least one night.

> Malcolm, for those interested in helping explore a possible radiant in this
> region, what TM Chart Numbers and observing times would you recommend?

If we knew the radiant location reliably, fields relatively close to
radiant (<20deg) are preferred because of the meteors swiftness.
Since we don't, it's better to enlarge the detection area.  Therefore
I'd choose fields 64 (13h12m, +40d); 65 (13h24m, +3d); 159 (11h08m,
-1d); 82 (10h42m, +33d).  These form an approximate rectangle centred
on the suggested radiant.  They should pinpoint the radiant given
sufficient meteors.  With this geometry there is a danger of the
diagonals passing through the radiant (field occlusion), but given the
likely low-at-best rate, an `X marks the spot' is just what we want.

I can supply pdf files of charts for those intending to observe
telescopically.  Serious requests only please.  Please give details of
your instrument (field of view, and aperture).  Those with small
binoculars can use Uranometria charts too, perhaps centred on a
brighter star in a pattern enclosing the possible radiant.

Being near the galactic pole the stars are relatively sparse.  Thus
locating the fields is harder.  If you find that, reserve fields are
61 (10h18m, +42.5d) near mu-lambda Uma for #82; 124 (11h15m, +12d)
near iota Leonis for #159.  Plotting is less reliable too, as there
are fewer field stars that closely bracket a meteor's path.

The low activity and the importance of seeing meteors from at least
two non-diagonal fields e.g. 82 and 159, 82 and 64, longer sessions
are strongly preferred, but we'll take whatever people can manage
in the cold.  I'd stick to the normal 20-30 minutes Teff per field
before switching to another region.  Start with the western pair.

As to the time of night, well that does depend on latitude to some
extent.  Given a choice I'd go for the radiant being at least 30
degrees altitude, i.e. in the small hours, to eek out as many meteors
as possible.  There are more sporadics then too.  On the other hand the
favoured nights are midweek, so it is expecting a lot.  Any
observations are better than none.

Clear skies,

Malcolm

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