S-band Spotlight

Observatories team up to reveal rare double asteroid!

New observations from multiple observatories, including Planetary Radar observations from the Arecibo observatory, have revealed the near-Earth asteroid 2017 YE5 to be an equal mass binary system. Find out more here!

About Us


The Planetary Radar Science group is a department of the Arecibo Observatory, which is an NSF facility operated under cooperative agreement by the University of Central Florida (UCF), Yang Enterprises, Inc. (YEI), and la Universidad Metropolitana (UMET). The Arecibo Observatory Planetary Radar program is fully funded by NASA's Near-Earth Object Observations program.

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Recently Observed Objects


For media inquiries, please contact our communications lead, Ricardo Correa

All observations in 2018 - most recent first

2018 TG6
2012 MM11
2018 TR4 - taken from confirmation page as ZT187A2!
2018 EB
2018 RC4
2018 RQ2
2004 DV24
2018 RB6 - taken from confirmation page as ZR8F0C0!
2018 QU1
1998 SD9
2015 QM3
(163899) 2003 SD220 - extremely strong radar target in December!
2015 FP118
2018 LQ2
(2061) Anza
2018 PL10
(420591) 2012 HF31
2018 MD7 (weak detection)
2018 NB
(398188) Agni
(439313) 2012 VE82
2018 NE1
2018 NM
2018 NV
(1627) Ivar
(13553) Masaakikoyama
2018 MB7
2017 YE5
(469737) 2005 NW44
(441987) 2010 NY65
(467309) 1996 AW1
2018 LK
2015 DP155
2018 EJ4
1999 FN19
2014 WG365
(68347) 2001 KB67
(66391) 1999 KW4
(96590) 1998 XB
2018 DH1
(1981) Midas
2018 FB
2018 FH1
2013 RZ73 - detected, but data corrupted
2017 VR12
2018 DT
(311554) 2006 BQ147
(3752) Camillo
2018 BH3
(505657) 2014 SR339
2018 BM5
(306383) 1993 VD
2018 AJ
2018 BT1 - taken from NEO Confirmation Page as ZBA33FE!
2018 AV2
2006 WE4
(438017) 2003 YO3
2017 XT61

Past Observations

Upcoming Radar Targets

The following table includes targets with submitted observing proposals. It is not comprehensive for targets of opportunity, especially newly discovered asteroids. For possible targets of opportunity and long-term future radar targets, updated daily, see: All asteroids visible today (SNR > 2/day), this month (SNR > 2/day), and in the next five years (SNR > 100/day). Note that these tables inevitably include objects that are currently "lost," often suggested by "1d" in the Type column, which stands for "one apparition with a days-long arc," so observer beware!

Object Dates Expected
H mag Request Optical
Request Optical
Request Optical
2012 MM11 Dec 05 Astrometry 19.0 PHA, period unknown
SURVEY NIGHT Dec 10-11 Astrometry All the things!
Comet Wirtanen Dec 10-18 Imaging Y Y COMET!
2003 NW1 Dec 12-13 Imaging Y 18.6 Y Y PHA, period unknown
2014 JU54 Dec 18 Astrometry 19.8 Period unknown
(163899) 2003 SD220 Dec 18-22 High-res Imaging 17.3 P = 285 h! Y PHA, NHATS, 285-h period
2012 MS4 Dec 20-21 Imaging 18.7 Period unknown
(418849) 2008 WM64 Dec 23, 25 High-res Imaging 20.7 PHA, 2.4-h period
2007 YQ56 Dec 29 Astrometry 19.9 PHA, period unknown
2016 AZ8 Jan 02-04 High-res Imaging 21.1 Y Y PHA, NHATS, period unknown
2004 XP14 Jan 02-03 High-res Imaging 19.7 PHA, 100-h(?) period
SURVEY NIGHT Jan 09-10 Astrometry All the things!

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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