(meteorobs) asteroid 2001 YB5 and delta Cancrids

  • Subject: (meteorobs) asteroid 2001 YB5 and delta Cancrids
  • From: Marco Langbroek
  • Date: Mon, 7 Jan 2002 21:02:27 +0100
Dear Huang Meng and others,

I just compared the orbit of 2001 YB5 with those given for the delta
Cancrids in the IMO handbook (orbit originating from Lindblad), by means of
Drummond's D' criterion. This compares and weights the orbital elements of
two orbits (asteroid and stream in this case) and expresses the similarity
in a D' value. The smaller this value, the higher the two orbits compare to
each other. The treshold value for likely association of two sets of orbits
is usually set at 0.105. The result I got for 2001 YB5 and the delta
Cancrids, is 0.170. This means that the association between the current
orbits of 2001 YB5 and the stream is not quite close and some caution in
directly linking them to each other is in order, although the difference is
not particularly large either... When I change the node and perihelion angle
of the stream in order to match those of 2001 YB5, but maintain the values
for a, e and q, the similarity does not improve but stays near 0.17

What someone should actually do, is run the full IAU meteor orbital database
through a D' comparison with 2001 YB5. There might be a chance that another
associated mid January stream turns up.

- Marco Langbroek (DMS)

ref.: J. Drummond, Icarus 45 (1981), 545

Marco Langbroek                    private: marco.langbroek@wanadoo.nl
Leiden University                     work: m.langbroek@arch.leidenuniv.nl
Faculty of Archaeology
P.O. Box 9515
NL-2300 RA Leiden
The Netherlands

"What seest thou else
  In the dark backward and abysm of time?"

William Shakespeare: The Tempest act I scene 2

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