#TeamRadar at the National Radio Astronomy Observatory is hiring someone to do the on-site work at the Green Bank Telescope: https://jobs.dayforcehcm.com/en-US/aui/CANDIDATEPORTAL/jobs/1313 .
This requires living in Green Bank, West Virginia, or lots of travel through the mountains.
Today on the #arXiv:
Nolan et al. 2026, "Planetary Radar at the Arecibo Observatory" - https://arxiv.org/abs/2604.00332
@mikeynolan , @lynncarter, and @PlanetTreky review everything that was done by #TeamRadar at Arecibo.
In the late 1990s, the Arecibo Observatory and its planetary radar system were upgraded to increase sensitivity by a factor of 20. This upgrade substantially improved the quality of the data and the ability to observe terrestrial planets, outer planet satellites, planetary rings, and near-Earth objects until the telescope's collapse in 2020. The higher sensitivity allowed radar observations of 889 near-Earth asteroids and comets from 1997 to 2020, compared to the 40 achieved in the previous 30 years, and showed that the population of near-Earth asteroids is heterogeneous, suggesting a wide variety of formation and evolution mechanisms. The planetary radar's ability to see through the atmospheres of Venus and Titan, into the shadows of Mercury and the Moon, and under the surface of the Moon and Mars provided a unique perspective on those bodies that has driven in-situ exploration. No other existing or planned facility matches the sensitivity that Arecibo had.
Today on the #arXiv:
Cannon et al. 2026, "The shape and spin state of (275677) 2000 RS11 from ground-based radar and optical observations" - https://arxiv.org/abs/2603.16703
Led by Richard Cannon, working with Agata Rożek and building on work Kaley Brauer did with me.
Near-Earth asteroid (275677) 2000 RS11 was observed over 5 days in March 2014 with both the Arecibo (2380 MHz, 12.6 cm) and Goldstone (8560 MHz, 3.5 cm) planetary radar systems. The continuous-wave spectra and delay-Doppler images collected revealed a sub-km-sized object with a strongly bifurcated shape. We used these radar observations, in combination with 7 optical lightcurves collected in 2014 and one lightcurve from 2023, to create a comprehensive shape and spin-state model for RS11. We find a rotation period of P = (4.445+-0.001) hours around a pole of lambda = (225+-80) and beta = (-80+-9) relative to the plane of the ecliptic. The shape of RS11 is unusual in that it does not resemble many of the other near-Earth asteroids modelled with ground-based radar. Whilst RS11 consists of a largely spherical, smaller lobe attached to an elongated, larger lobe via a narrow neck, the smaller lobe is not aligned with the long axis of the larger lobe, but is closer to the larger lobe's shortest principal axis. In combination with a large concavity observed on the outer face of the larger lobe, this may point to an unusual formation or event in the object's past. We estimate that RS11 has an geometric albedo of (0.16+-0.06) and a radar albedo between 0.08 and 0.16. Analysis of its gravitational environment reveals that for standard S-type asteroid densities, we would not expect rotational instability and it is possible for RS11 to be a low tensile strength rubble-pile asteroid.
These results for Nereus are consistent with those from #TeamRadar in 2009 (11º pole direction offset with uncertainties of ±10º).
https://echo.jpl.nasa.gov/asteroids/4660_Nereus/brozovic.etal.2009.nereus.pdf
As well as it being unavailable for spacecraft communications; #TeamRadar observations with DSS-14 have been canceled since September: https://echo.jpl.nasa.gov/asteroids/goldstone_asteroid_schedule.html
QT SpaceNews @spacenewsinc.bsky.social
2025 November 11
Key antenna in NASA’s Deep Space Network damaged
One of the largest antennas in NASA’s Deep Space Network was damaged in September and may be out of service for an extended period, further straining the system.
https://spacenews.com/key-antenna-in-nasas-deep-space-network-damaged/
https://bsky.app/profile/spacenewsinc.bsky.social/post/3m5e7ogiros2z
Lazio et al. 2025, "The Next-Generation Ground-Based Planetary Radar" - https://www.kiss.caltech.edu/final_reports/NextGeneration-PlanetaryRadar-final%202025-09-19.pdf
Emerson Wittaker: talking about near earth asteroid binary 1999 KW4: Moshup 1.5km and Squannit 0.5km, mutual orbit in 17 hours. Measured by #TeamRadar from Arecibo (😭)
Evolution of system depends on YORP effect, relative spins of bodies, and shapes.
Doing shape-model libration simulations now.
Today on the #arXiv :
White et al. 2025, "Ground-Based Radar Tracking of Near-Earth Objects With VLBI Radio Telescopes: 2024 MK Test Case" - https://arxiv.org/abs/2509.15684
Transmitting with DSS-43 and DSS-35 and receiving with antennas across Australia.
The Southern Hemisphere Asteroid Research Project is an active and informal entity comprising the University of New South Wales, the University of Tasmania, the University of Western Australia, and the Curtin University, which performs asteroid research in collaboration with federal agencies, including the Commonwealth Scientific and Industrial Research Organisation and the National Aeronautics and Space Administration (JPL). Since 2015, we have used the Australian infrastructure to characterize more than 50 near-Earth asteroids through bistatic radar observations. On 29 June 2024, we used four very long baseline interferometer (VLBI) radio telescopes to follow the close approach of 2024 MK to the Earth. In this paper, we describe the detections and the analysis of VLBI and howthese observations can help to improve the understanding of its composition and orbit characterization.
Michael Busch
Prof. Sam Lawler