Circular No. 5695

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.

Telephone 617-495-7244/7440/7444 (for emergency use only) TWX 710-320-6842 ASTROGRAM CAM EASYLINK 62794505

MARSDEN@CFA or GREEN@CFA (.SPAN, .BITNET or .HARVARD.EDU)

1993 BC_{2}

E. Helin and P. Rose report their discovery of a fast-moving asteroidal object on films taken with the 0.46-m Schmidt telescope at Palomar by Helin, K. Lawrence, and Rose. The following positions were measured by Rose (clouds were present during the last two exposures on Jan. 21):

1993 UT  α_{2000}  δ_{2000}  Mag.
Jan. 21.25122  6^{h}15^{m}43.^{s}55  +23^{o}24′04′′.7  14.0
21.25538  6 15 45.50  +23 23 49.6
21.26910  6 15 52.38  +23 22 54.7
21.27326  6 15 54.35  +23 22 41.7
22.10399  6 23 19.96  +22 29 40.2
22.10955  6 23 22.55  +22 29 18.9
22.25503  6 24 33.78  +22 20 12.2
22.26059  6 24 36.25  +22 19 52.8
22.38785  6 25 38.16  +22 11 33.2
22.39271  6 25 40.22  +22 11 20.7

Preliminary orbital elements from eight of the above observations:

T = 1993 Jan. 10.172 TT  ω = 167.^{o}892
e = 0.43105  Ω = 299.275 }2000.0
q = 1.05036 AU  i = 4.098

a = 1.84613 AU n^{o} = 0.392925 P = 2.51 years

1993TT α_{2000}  δ_{2000}  Δ  r  ϵ  β  V
Jan. 23 6^{h}30.^{m}98 +21^{o}32.^{′}8 0.083 1.060 154.^{o}1 24.^{o}0 13.4
25 6 47.59 +19 24.3 0.085 1.063 155.9 22.3 13.4
27 7 03.19 +17 17.7 0.088 1.067 157.4 20.8 13.4
29 7 17.70 +15 15.8 0.091 1.071 158.6 19.6 13.4
31 7 31.12 +13 20.7 0.095 1.075 159.5 18.8 13.5
Feb. 2 7 43.45 +11 33.7 0.100 1.080 160.1 18.1 13.6
4 7 54.76 + 9 55.5 0.105 1.085 160.4 17.7 13.7
6 8 05.10 + 8 26.5 0.110 1.091 160.6 17.5 13.8
8 8 14.55 + 7 06.6 0.116 1.097 160.6 17.4 13.9
10 8 23.19 + 5 55.5 0.122 1.103 160.4 17.4 14.1
12 8 31.08 + 4 52.5 0.129 1.110 160.2 17.5 14.2

1993 January 22 Daniel W. E. Green