Electronic Telegram No. 5438
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
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Prepared using the Tamkin Foundation Computer Network


2024 RW_1
     P. Veres, Minor Planet Center, reports on MPEC 2024-R68 that Jacqueline
B. Fazekas (Lunar and Planetary Laboratory, University of Arizona) relayed to
the MPC observations of a fast-moving object discovered on CCD images obtained
with the Mt. Lemmon Survey's 1.5-m reflector on Sept. 4.24 UT; after
additional observations arrived via the object's posting on the NEOCP webpage,
the MPC realized that this object (designated 2024 RW_1) had a "non-zero
impact probability with the earth", with an apparent prediction of impact near
Luzon island (The Philippines).  Veres writes that the time and location of
the impact (Sept. 4.694) were "well-defined hours before the impact" by the
Scout system of the "Center for Near Earth Object Studies" (JPL) and by the
European Space Agency's Meerkat system, so that the public in Luzon were
made aware and numerous videos have already been posted online (e.g., at URL
https://www.imo.net/2024-rw1-atmospheric-entry-in-pictures-videos/).  This
is the ninth asteroidal object to be discovered from ground-based telescopes
prior to impacting the earth's atmosphere (cf. CBETs 5221, 5230, 5334).
     P. Jenniskens, SETI Institute and Ames Research Center (NASA), points out
that the early fragmentation seen in recorded videos from eastern Luzon, as
well as the early rise in the meteor's brightness, the long wake, and the
numerous flares, combined with the low inclination of the impact orbit and its
semi-major axis being in the 3:1 mean-motion resonance with Jupiter, suggest
that 2024 RW_1 may have been a CM2 carbonaceous-chondrite-type object (cf.
Jenniskens 2024, LPI Contribution No. 3036, id. 6098).


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2024 CBAT
2024 September 4                 (CBET 5438)              Daniel W. E. Green