[meteorite-list] Holy crap-- can anyone confirm this? Any, vikingson the list?
From: Marco Langbroek <marco.langbroek_at_meteoritecentral.com>
Date: Mon Jun 12 14:32:01 2006 Message-ID: <448D9DCA.4000003_at_wanadoo.nl> 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 ----- Dr Marco Langbroek Dutch Meteor Society (DMS) e-mail: meteorites_at_dmsweb.org private website http://home.wanadoo.nl/marco.langbroek DMS website http://www.dmsweb.org ----- Received on Mon 12 Jun 2006 01:00:58 PM PDT |
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