S-band Spotlight

(226514) 2003 UX34

Arecibo and Goldston planetary radar observations of potentially hazardous asteroid (226514) 2003 UX34 reveal it is a binary system! (left) Summed delay-Doppler image over 2 hours. The wider echo is the larger (~250 m), more rapidly rotating primary asteroid and the narrower smudge in front is the smaller, more slowly rotating secondary asteroid. The smudging of the secondary is due to its motion in its orbit about the primary over the 2 hours of data combined to make this radar image. The void in the smudge occured when data was not taken. (right) Gif demonstrating the orbit of the secondary about the primary; each frame is a sum of 3 minutes of data.
NEA 2003 UX34 was discovered in October 2003 by Spacewatch at Kitt Peak. At its closest approach this year, it will be within a distance 19 times the Earth-Moon distance. For more information, please visit the JPL Planning page: 2003 UX34

About Us


The Planetary Radar Science group is a department of the Arecibo Observatory, which is an NSF facility operated under cooperative agreement by SRI International, Universities Space Research Association (USRA), and la Universidad Metropolitana (UMET). The Arecibo Observatory Planetary Radar program is fully funded through a grant to USRA from NASA's Near-Earth Object Observations program (Grant #NNX12AF24G and NNX13AQ46G).

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Recently Observed Asteroids:


For media inquiries, please contact our USRA communications lead, Dr. Edgard G. Rivera-Valentin

All detections in 2017 - most recent first

163693 Atira - BINARY! Observations at other wavelengths encouraged!
(265482) 2005 EE
(438955) 2010 LN14
2016 YC8
(85990) 1999 JV6
2016 YB8
4179 Toutatis - initially detected in late December 2016
1991 VK - initially detected in late December 2016
(226514) 2003 UX34 - BINARY! Observations at other wavelengths encouraged!
2102 Tantalus

Past Asteroid Detections

Detections in 2016

Detections in 2015

Detections in 2014

Detections in 2013

Observing statistics since 1998

Upcoming Radar Targets:

Asteroid Dates Expected
H mag Request Optical
Request Optical
Request Optical
2102 Tantalus Jan 01-07 Imaging Y 16.0 Y Binary?, PHA, 2.4-h period, Yarkovsky?
226514 (2003 UX34) Jan 04-06 High-res Imaging 20.0 Y Y BINARY!, PHA, period unknown
85990 (1999 JV6) Jan 14-15 Imaging 20.2 Y Peanut, 6.5-h period, Xk type
163693 Atira Jan 20 Astrometry 16.3 Y Y BINARY!, 2.97-h period
2015 BN509 Feb 01-13 High-res Imaging 20.6 Y Y PHA, period unknown
443103 (2013 WT67) Feb 03-24 High-res Imaging 18.0 Y Y PHA, 135-h period
Comet 45P/HMP Feb 07-16 Imaging Y Comet!
2014 QC3 Feb 16-17 Imaging 20.7 Y Y PHA, period unknown
16 Psyche Feb 24-05 Spectra MBA, 4.2-h period
Comet 41P/TGK Feb 28-08 Spectra Y Comet!
Venus Mar 21-27 Imaging Venus!
215588 (2003 HF2) Mar 22-03 High-res Imaging 19.4 Y Y PHA, period unknown
143404 (2003 BD44) Mar 31-May 07 High-res Imaging Y 16.8 Y Y PHA, period unknown
2014 JO25 Apr 12-20 High-res Imaging Y 18.1 Y Y Y PHA, period unknown
2016 JP Apr 18-20 Imaging 21.3 Y Y PHA, period unknown
Moon Apr 26-28 Imaging Moon!
Comet 41P/TGK May 09-17 Spectra Y Comet!
2007 LE May 23-28 Imaging 19.0 Y Y BINARY, PHA, 2.6-h period
Moon May 24-26 Imaging Moon!
418094 (2007 WV4) May 31 High-res Imaging 19.3 Y Y PHA, period unknown
90075 (2002 VU94) May 20-05 Imaging Y 15.2 Y PHA, 7.88-h period
6063 Jason Jun 02-10 High-res Imaging Y 15.9 Y Y 51.7-h period
441987 (2010 NY65) Jun 13-05 High-res Imaging 21.5 Y Y PHA, 4.98-h period, Yarkovsky?
2010 VB1 Jun 16-22 High-res Imaging 23.4 Y Y NHATS, period unknown
190166 (2005 UP156) Jun 06-Aug 11 High-res Imaging Y 17.1 Y Y 40.5-h period

Requests for Optical Observations:

Astrometry: optical astrometry is specifically requested for objects with plane-of-sky pointing uncertainties of tens of arcseconds or more. Optical observers are asked to submit astrometry to the Minor Planet Center as soon as possible after observations.

Lightcurves: optical lightcurves and period estimates are specifically requested for objects that will produce high-resolution images (i.e., possible shape models), for targets of IRTF thermal-infrared observations, for candidate binary asteroids, and for potential human-exploration targets. Lightcurve observers are asked to relay period estimates to the radar team to help with the planning of radar observations. During the analysis and modeling process, the radar team may request to use available lightcurve data.

Characterization: optical characterization refers to spectra and colors, which are most important for targets of IRTF thermal observations, for completeness of the strongest radar targets, for candidate binary asteroids, and for potential human-exploration targets. Optical observers are asked to relay probable spectral-class information to the radar team to compare with characteristics suggested by radar.

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