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We report results of Canberra-ATCA Doppler-only continuous wave (CW) radar observations of near-Earth asteroid (163899) 2003 SD220 at a receiving frequency of 7159 MHz (4.19 cm) on 2018 December 20, 21, and 22 during its close approach within 0.019 au (7.4 lunar distances). Echo power spectra provide evidence that the shape is significantly elongated, asymmetric, and has at least one relatively large concavity. An average spectrum per track yields an OC (opposite sense of circular polarisation) radar cross section of 0.39, 0.27, and 0.25 km$^{2}$, respectively, with an uncertainty of 35 %. Variations by roughly a factor of two in the limb-to-limb bandwidth over the three days indicate rotation of an elongated object. We obtain a circular polarization ratio of 0.21 $pm$ 0.07 that is consistent with, but somewhat lower than, the average among other S-class near-Earth asteroids observed by radar.
We observed the near-Earth asteroid 2008 EV5 with the Arecibo and Goldstone planetary radars and the Very Long Baseline Array during December 2008. EV5 rotates retrograde and its overall shape is a 400 /pm 50 m oblate spheroid. The most prominent sur
Planetary radar observations offer the potential for probing the properties of characteristics of solid bodies throughout the inner solar system and at least as far as the orbit of Saturn. In addition to the direct scientific value, precise orbital d
We present a fireball detected in the night sky over Kyoto, Japan on UT 2017 April 28 at ${rm 15^{h},58^{m},19^{s}}$ by the SonotaCo Network. The absolute visual magnitude is $M_{rm v}$=$-$4.10$pm$0.42mag. Luminous light curves obtain a meteoroid mas
We report on observations of near-Earth asteroid 2011 MD with the Spitzer Space Telescope. We have spent 19.9 h of observing time with channel 2 (4.5 {mu}m) of the Infrared Array Camera and detected the target within the 2{sigma} positional uncertain
We conducted a polarimetric observation of the fast-rotating near-Earth asteroid (1566) Icarus at large phase (Sun-asteroid-observers) angles $alpha$= 57 deg--141deg around the 2015 summer solstice. We found that the maximum values of the linear pola