Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 4999: 1989c1; 1990a; RY Sgr

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 4998 SEARCH Read IAUC 5000
IAUC number 

                                                  Circular No. 4999
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 or GREEN@CFA.BITNET    MARSDEN or GREEN@CFAPS2.SPAN


COMET AUSTIN (1989c1)
     M. F. A'Hearn and J. J. Klavetter, University of Maryland,
report: "A series of short CCD exposures, with the Lowell Observatory
1.07-m telescope in bright twilight centered at Apr. 20.50 UT,
yield a very approximate CN production rate of 3 x 10E27 sE-1.
This is roughly the same production rate as that of P/Halley at the
time of the spacecraft encounters."
     Total visual magnitude estimates (cf. IAUC 4997):  Apr. 19.24
UT, 4.8 (M. Kidger, Canary Is., 10x50 binoculars; 4 deg tail); 21.21,
4.7 (A. Pereira, Cabo da Roca, Portugal, 9x34 binoculars); 22.10,
5.3 (A. Dalle Donne, Bologna, Italy, 8x30 binoculars; 2.5 deg tail);
23.43, 5.3 (G. Kronk, Troy, IL, 20x80 binoculars; tail about 1 deg
in p.a. about 315 deg); 24.36, 5.3 (J. E. Bortle, Stormville, NY,
10x50 binoculars; 3 deg tail in p.a. 319 deg).


PERIODIC COMET WILD 4 (1990a)
     Ephemeris from orbital elements on MPC 16205:

     1990 ET      R.A. (1950) Decl.     Delta      r       m1
     Apr. 19     9 09.36    +19 40.6    1.558    2.070    13.1
          29     9 19.58    +18 27.8
     May   9     9 32.04    +17 03.8    1.725    2.033    13.3
          19     9 46.29    +15 29.2
          29    10 01.99    +13 44.6    1.899    2.007    13.4
     June  8    10 18.84    +11 50.6
          18    10 36.57    + 9 48.4    2.074    1.992    13.6

     Total visual magnitude estimates (cf. IAUC 4994):  Apr. 15.85
UT, 12.9 (J. Jahn, Bodenteich, West Germany, 0.20-m reflector);
19.09, 12.9 (J. E. Bortle, Stormville, NY, 0.32-m reflector); 22.23,
11.8 (C. S. Morris, Pine Mountain Club, CA, 0.26-m reflector).


RY SAGITTARII
     This R CrB-type variable has begun to fade, as indicated by the
following visual magnitude estimates (cf. IAUC 4673):  Mar. 3.85 UT,
6.6 (H. Narumi, Ehime, Japan); Apr. 2.79, 6.3 (Narumi); 6.85, 6.4 (A.
Pearce, Scarborough, W. Australia); 17.81, 7.5 (Narumi); 18.75, 7.5
(M. Yamada, Ishikawa, Japan); 22.82, 8.0 (Pearce); 23.78, 8.0 (Pearce).


1990 April 24                  (4999)             Daniel W. E. Green

Read IAUC 4998 SEARCH Read IAUC 5000

Our Web policy. Index to the CBAT/MPC/ICQ pages.

Valid HTML 4.01!