CBET 4981 : 20210620 : (4337) ARECIBO
Electronic Telegram No. 4981
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network

Report submitted to CBAT: (4337) ARECIBO

David Gault and Peter Nosworthy report the discovery of a satellite of the minor
planet (4337) Arecibo, from the occultation of the star UCAC4 323-126197 on 2021
May 19.74861. The observers were separated by 0.7 km across the occultation path,
and 18 km along the path. Both observations were made using GPS time-stamped video.

Both observers recorded two occultation events with the following characteristics.

Observer         Location                 Chord Lengths
                 (Australia)            Main body    Satellite
D Gault          Hawkesbury Heights      18.7 km      5.6 km
P Nosworthy      Hazelbrook              19.7 km      2.6 km






    




Richard Nolthenius and Kirk Bender report the confirmation of the satellite from
the occultation of the star UCAC4 322-116848 on 2021 June 9.45736. The observers
were separated by 8.2 km across the occultation path, and 8 km along the path.
Both observations were made using GPS time-stamped video.

Both observers recorded two occultation events with the following characteristics.

Observer         Location                  Chord Lengths
                 (California)            Main body    Satellite
R Nolthenius     San Ardo                 23.9 km      11.7 km
K Bender         Bradley                  20.8 km      13.0 km






    




The sizes of both the main body and the satellite were poorly determined by the
first occultation, because of the close across-path separation of the observers.
The sizes of both bodies were well determined from the second occultation, because
the across-path separation was larger, and the chords were favourably positioned
against both bodies. On the assumption that the bodies presented a circular
profile, the diameters determined from the second occultation are:

   Main body  24.3 ± 0.6 km
   Satellite  13.0 ± 1.5 km

These diameters were used to derive the position of the satellite relative to the
main body, for both occultations. Those positions are:

   2021 May 19.74861 25.5 ±1.0 mas in PA 105.2° ±1.0°
   2021 June 9.45736 32.8 ±0.7 mas in PA  94.3° ±2.7°