Planetary Sciences

The Arecibo Planetary Radar is used to study celestial bodies in our solar system such as planets, moons, asteroids and comets. Directed by the 1000-foot reflector, a powerful beam of radio energy is transmitted in the direction of the target object. A small portion of this energy is reflected by the target, back in the direction of earth. This radio echo is processed then analyzed to yield information about the size, shape, spin, density, composition, surface properties, and geology (e.g., ridges, craters, and boulders) of the target object. The Arecibo Planetary Radar System can measure the distance to an asteroid, typically millions of km away, with a precision of meters; it can measure the speed of an asteroid, typically tens of kilometers per second, with a precision of millimeters per second. Arecibo’s precision can greatly refine asteroid orbits, aiding NASA in its congressionally mandated mission to study near-Earth objects and helping assess the impact hazard of potentially hazardous objects.

Science Group

The Planetary Radar Science group is a department of the Arecibo Observatory, which is an NSF facility operated under cooperative agreement by SRI International, USRA, and la Universidad Metropolitana (UMET). The Arecibo Observatory Planetary Radar program is fully funded through grants to USRA from NASA's Near-Earth Object Observations program (Grants NNX12AF24G and NNX13AQ46G). The Planetary Radar Science group is also partnered with the Center for Lunar Science and Exploration node (USRA-Lunar and Planetary Institute/NASA-Johnson Space Center) of the NASA Solar System Exploration Research Virtual Institute program.

Recent News
April 17, 2017

Delay-Doppler image (left) captured by the AO Planetary Radar System. In this image, the peanut-shaped nature of this asteroid is readily visible as well as potential geologic features, such as a peak on the fro nt half of the asteroid and a rounded double-lobed nature to the back half of 2014 JO25. (right) Movie of the rotation of 2014 JO25 produced by combining several delay-Doppler images. Read More

February 12, 2017

Only the seventh comet imaged using radar! E. Howell, C. Lejoly, E. G. Rivera-Valentin, L. F. Zambrano-Marin, A. Virkki report that Arecibo (2380 MHz, 12.6 cm) delay-Doppler images obtained on 12 February 2017 reveal Comet 45P/HMP is somewhat larger than previously estimated, at a size of 1.3 km and a rotation period of 7.6 hrs. Read More

January 20, 2017

Discovery Announcement of Binary System (163693) Atira. E. G. Rivera-Valentin, P. A. Taylor, A. Virkki, and B. Aponte-Hernandez report that Arecibo (2380 MHz, 12.6 cm) delay-Doppler radar images obtained on 2017 January 20 and 23 reveal near-Earth asteroid (163693) Atira is a binary system. Visible range extents of the components in images with 150 m/pixel resolution suggest a primary up to 4.8 ± 0.5 km in diameter and a secondary 1.0 ± 0.3 km in diameter. Read More

S-band Spotligh

Near-Earth Asteroid 2014 JO25

2014 JO25 (Animation)

2014 JO25 (Animation) - Apr 17, 2017

2014 JO25 (Snapshot)

2014 JO25 (Animation) - Apr 19, 2017


[ Publications section is currently under construction]

Press Releases

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[Schedule section is currently under construction]


[Instruments section is currently under construction]

Planetary Radar Group


Dr. Patrick Taylor

Planetary Radar Group Lead

Dr. Edgard G. Rivera-Valentin

Staff Planetary Scientist jointly with the LPI

Dr. Anne Virkki

Postdoctoral Research Scientist

Dr. Sriram Bhiravarasu

Postdoctoral Research Scientist
Dr. Flaviane Venditti

Dr. Flaviane Venditti

Postdoctoral Research Scientist
Dr. Sean  Marshall

Dr. Sean Marshall

Postdoctoral Research Scientist

Luisa Fernanda Zambrano-Marín

Research Asst./ Graduate Student

Betzaida Aponte

Project Specialist / Observing Support

Linda Ford

Project Specialist / Data Manager

Anthony Ford


Graduate Students
  1. Jenna Crowell, University of Central Florida, Advisor: Yan Fernandez
  2. Agata Rozek, University of Kent, Advisor: Stephen Lowry
  3. Adam Greenberg, University of California, Los Angeles, Advisor: Jean-Luc Margot
  4. (Undergraduate) Benjamin Sharkey, University of Minnesota, Twin Cities, Advisor: Charles Woodward

  1. Michael C. Nolan, Staff Scientist, Head of Planetary Radar, and Site Director
  2. Ellen S. Howell, Staff Scientist
  3. Alessondra Springmann, Data Analyst
  4. John K. Harmon, Staff Scientist
  5. Alice A. Hine, Staff Scientist
  6. Jean-Luc Margot, Postdoc
  7. Donald B. Campbell, Staff Scientist and Site Director
  8. Carolina Rodriguez Sanchez-Vahamonde, Research Assistant / Observing Support