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Jazlan
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« Reply #2 pada: December 27, 2009, 09:49:09 PM » |
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Draconids (Giacobinids) 2018
Earth will be passing the node of comet 21P/Giacobini-Zinner (parent comet of the Draconids) in 2018, only 22.7 days after the comet itself has passed by this same region of space. According to meteor expert Joe Rao, the separation between the respective orbits of Earth and the comet will be 0.017 AU, that is roughly midway between the situation that produced a storm over Europe in 1933 (ZHR = 5000) and a heavy shower over Japan in 1985 (ZHR ~ 800).
No accurate projections have yet been made for the 2018 Draconids shower, but applying the old "analog method" of matching Earth's orbit relative to that of the parent comet, Don Yeomans of NASA/JPL calculated the nodal crossing time should be near October 9.0 UT (the Moon will be new on this occasion).
Schwassmann-Wachmann3-ids 2022
Comet 73P/Schwassman-Wachmann 3 did fragment during its 1995 perihelium passage. Considerable amounts of dusts likely have been ejected during that passage, according to work by Hartwig Luethen, Rainer Arlt and Michael Jaeger. The comet and also its dust trails are very much subject to perturbations, which spreads the area of possible meteor radiants across a vast portion of the sky in the Boo/Cvn area. Although the meteors, originating from comet 73P, are sometimes called Tau Herculids, it is evident that one should avoid this expression, given the broad radiant size.
The dust trail of the famous 1995 passage of comet 73P will be encountered by Earth in 2022 on May 31.205 UT at a 'miss distance' of only 0.0004 AU. Peak levels could be very substantial. The moon will be new at that time, and best observing conditions are in the USA.
There are more encounters with dust trails, which have been released at other (probably more normal) returns of the comet, in 2011 and 2017.
Perseids 2028
In 2028, Earth will pass within about -0.0004 AU of the 4-revolution trail, produced by parent comet P/Swift-Tuttle in 1479. Lyytinen expects this encounter to produce a real storm activity of the Perseids, on August 12.229 UT. Most favorable viewing location will be the USA, although the moon will seriously interfere.
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