Elton
[EMAIL PROTECTED] wrote:
Ron, �� Boo !! as in as in Bootes (formerly somewhat known as Quadrans Muralis), not to pronounce like the "oo" of booties. The latest news on the Quadrantids' meteor shower radiating from Bootes. Sounds like there may have been some major booty shaking and perhaps disintegration of the parent body 2003 EH 1. I can't resist asking if anyone can correlate any Jan 3 or (Jan 4?) falls, or there about. This should be a fresh research question. Anne from Impactika.com has listed the following falls for that date:
*
Jan 2 (none)
Jan 3 1877* Warrenton *1903* St. Mark's *1970* Lost City
*Jan 4, 5 (none)
*Saludos Doug Dawn Mexico
http://leonid.arc.nasa.gov/IAUCircular2003Dec8.txt
2003 EH_1 AND THE QUADRANTIDS P. Jenniskens, NASA Ames Research Center, has pointed out that 2003 EH_1 (cf. MPEC 2003-E27) would seem to be a very strong candidate for the parent of the Quadrantid meteor stream. The later orbits, from arcs of up to 48 days (MPO 48330), indicate that frequent approaches within 0.2-0.3 AU of Jupiter occur, those during the past century or two evidently increasing q from just under 1 AU (with other orbital elements also very similar to those of the Quadrantids) to the present 1.19 AU. The current theoretical radiant for 2003 EH_1 (R.A. = 229.9 deg, Decl. = +49.6 deg; V_inf = 41.7 km/s at solar longitude 282.94 deg, equinox 2000.0) is at the center of the Quadrantid radiants measured by photographic means, the narrow dispersion implying a young (about 500 years) shower age. From that dispersion, Jenniskens et al. (1997, Astron. Astrophys. 327, 1242) suspected that the parent was still among the meteoroids, hiding as a minor planet. On computing a parabolic orbit for C/1490 Y1, Hasegawa (1979, Publ. Astron. Soc. Japan 31, 257) introduced that comet as the likely Quadrantid parent. In attempting to link the 2003 observations to those of 1490-1491, Jenniskens, and also B. G. Marsden (Center for Astrophysics), have found that most of the potential solutions with the required Jan. 1491 perihelion date yield 0.5 < q < 0.6 AU in 1491, and this is probably too small to fit the data used by Hasegawa. Values in the more acceptable range of 0.7 < q < 0.8 AU (and 0.80 > e > 0.75) certainly arise for 1488 < T < 1494, however, the desired date being clearly attainable with the help also of a close approach to the earth or -- more likely -- the presence of nongravitational forces. Further light could be shed on the problem by the recognition of precovery and/or recovery observations of 2003 EH_1, which is presumably a comet and that should in any case be considered a high-priority object for further study.
(C) Copyright 2003 CBAT 2003 December 8 (8252) Daniel W. E. Green
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