Electronic Telegram No. 1382 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions) CBAT@CFA.HARVARD.EDU (science) URL http://www.cfa.harvard.edu/iau/cbat.html 2008 HJ R. Miles, Stourton Caundle, Dorset, UK, reports that photometric observations of minor planet 2008 HJ (cf. MPEC 2008-H26, MPO 139312), obtained using the 2.0-m Faulkes Telescope South during Apr. 28-29, reveal that this Apollo-type object has the shortest known rotation period of any natural body in the solar system at 42.67 +/- 0.04 s. It exhibits a light curve comprised of two similar maxima and minima with an amplitude of 0.8 mag. Assuming an absolute magnitude of H = 25.8 and a geometric albedo of 0.2, 2008 HJ has presumed approximate dimensions 12 x 24 m. The fastest previously known rotator was 2000 DO8, which has a rotation period of 78 s (Whiteley et al. 2002, Icarus 157, 139). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2008 CBAT 2008 May 22 (CBET 1382) Daniel W. E. Green