Central Bureau for Astronomical Telegrams
IAUC 3691: Apr. LYRID METEORS; (1009)
The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).
Read IAUC 3692
Circular No. 3691
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
TWX 710-320-6842 ASTROGRAM CAM Telephone 617-864-5758
APRIL LYRID METEORS
Visual observers in Florida and Colorado have reported a brief,
unusually intense, return of the April Lyrid meteor stream. At the
peak of the display, around Apr. 22d06h50m UT (corresponding to
solar longitude 31o.38; cf. for the associated comet 1861 I at epoch
1861.4 Node = 31o.17; equinox 1950.0), these observers recorded 3-5
Lyrids per minute. For the hour centered on the peak the observed
hourly rate was ~ 75 (corresponding to ZHR ~ 90-100). The observed
hourly rates were less than 20 during the preceding and the following
hours. The brightest meteors were of mag -2.0 to -3.0. Observers
were N. McLeod, III, Fort Myers, FL; P. Jones, St. Augustine,
FL; H. Povenmire, Indian Harbour Beach, FL; T. Schmidt, Colorado
Springs, CO; and M. Adams, Palm Bay, FL. Any other observers who
witnessed the event are encouraged to forward their observations to
M. Adams at P.O. Box 863, Palm Bay, FL 32905, U.S.A.
(1009) SIRENE
L. K. Kristensen, Institute of Physics, University of Aarhus;
writes that photoelectric observations by P. Gammelgaard, Ole Romer
Observatory, of the comparison stars originally used suggest that
this object, one of the seven remaining numbered minor planets lost
since their discovery oppositions, may be brighter than shown in
Efemeridy Malkyh Planet for 1982. The following alternative ephemeris
is from new computations by Kristensen. The object should be
1 mag brighter still at the opposition in 1984 Mar., but the Variation
will then be twice what it is this year.
For dT = +1d
1982 ET R. A. (1950) Decl. Delta r dR.A. dDecl. Mag.
May 11 19 11.74 - 8 39.9 2.584 3.214 -0m72 - 2'9 20.3
21 19 09.78 - 7 40.4
31 19 05.56 - 6 44.3 2.305 3.144 -0.81 - 3.3 19.9
June 10 18 59.20 - 5 54.3
20 18 50.97 - 5 12.8 2.109 3.069 -0.87 - 3.7 19.5
30 18 41.43 - 4 42.5
July 10 18 31.37 - 4 25.2 2.017 2.990 -0.88 - 4.0 19.3
20 18 21.65 - 4 21.5
30 18 13.14 - 4 31.0 2.033 2.908 -0.82 - 3.9 19.4
Aug. 9 18 06.55 - 4 51.6
19 18 02.32 - 5 20.8 2.135 2.821 -0.73 - 3.6 19.6
1982 April 28 (3691) Brian G. Marsden
Read IAUC 3692
Our Web policy. Index to the CBAT/MPC/ICQ pages.
