Radar detection of centimeter‐sized orbital debris: Preliminary Arecibo observations at 12.5‐CM wavelength

Orbital debris objects with sizes of 6 mm and larger were detected when they passed through the main beam of the high‐power, 12.6‐cm wavelength radar at the Arecibo Observatory. The number of objects detected at altitudes below 1000 km in the size range of 6 mm to 2 cm agreed with orbital debris model predictions to better than a factor of two. Radar detections of larger orbital debris (10‐cm diameter and above) were also compared with the objects in the U.S. Space Command catalog (the cataloged objects have UHF radar cross‐sections larger than 0.01 m2). This experiment demonstrated that the large, Earth‐based radar telescopes normally used for planetary studies can provide useful data about the near‐Earth orbital debris populations.