Sterling K. Webb wrote:
Yes, the beta Taurid stream is broad and diffuse; they
cover the entire Earth. Do we notice more hits in the
northern hemisphere because we live there, because it
has more people, etc.? I empirically count more big
ones in the northern hemisphere
What empirical data? What we know of beta Taurids is through radar and radio MS
data from both hemispheres.
And whether or not a stream covers one hemisphere only or both, has nothing to
do with how diffuse the stream is. It is purely a function of the radiant's
declination. You don't see it (visually or by radar) in areas where the radiant
does not rise over the horizon because its declination is either too high north
or too high south. With a declination of (roughly) +25 degrees the beta Taurids
are visible from both hemispheres (by radar only as the radiant is too close to
the position of the sun, hence rises in daylight). Only an extreme southern
latitude like Antarctica is a wrong place to be. The optimal place
(theoretically highest influx per hour) is at 25 degrees northern latitude.
The beta Taurid stream is so broad and diffuse that
the radiant is very imprecise. They last for 30 days. The
"stream" has many varied components, is not well
understood nor mapped, and again, disputed.
Basically its the same stream (it are the same particles, in similar orbits,
with a similar origin) as the November Taurids, a nighttime stream which is
better studied. The beta Taurids is where we see this stream when earth
encounters the other node of the stream orbit. Both streams last long, indeed,
as the stream sensu lato is dispersed along the ecliptic. The radiant area is
more or less "on" the ecliptic, with two substreams just a few degrees south and
just a few degrees north of it (and I assume this is what you mean with a
"retrograde" component).
Known meteor streams account for only a portion
of the objects that enter the atmosphere. We call the
rest "erratics,"
More properly: "sporadics"
- Marco
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Dr Marco Langbroek
Dutch Meteor Society (DMS)
e-mail: [EMAIL PROTECTED]
private website http://home.wanadoo.nl/marco.langbroek
DMS website http://www.dmsweb.org
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