A Holistic Approach to Understanding Asteroids

Image of laboratory setup at York University used for Dr. Hickson’s experimental study of the electromagnetic properties of mineral powders..

Planetary

Asteroids, though often simply considered “rocks in space,” are actually composed of an array of different materials. It is important to know what asteroids are made of in order to determine the structure and formation of asteroids, and to assess any risk that an individual asteroid would pose if on a collision course with Earth.

A recent study led by AO postdoctoral researcher Dr. Dylan Hickson, published in the Journal of Geophysical Research: Planets, takes a holistic approach at interpreting planetary radar data to better understand asteroid composition.

“We conducted laboratory experiments on various mineral powders at different densities to measure the corresponding change in their electrical properties,” Dr. Hickson explained. “We compared these laboratory measurements with known theoretical models and combined them with radar scattering models to infer the density of asteroid surfaces observed using radar.” This work was conducted at York University.

These theoretical models are the ones that are used to decipher planetary radar observations, like those obtained at the Arecibo Observatory, so it was important to see how accurately the models reflected the laboratory studies. Without in-depth knowledge of how the electrical properties, like permittivity, scatter the radar signals, interpreting planetary radar observations can be challenging.

“That’s why this research was exciting to me,” Dr. Hickson related. “We used both laboratory experimentation and theoretical modeling to address a specific problem in planetary radar.” “These two sides to the story are necessary to get the full picture,” he continued. “Having the opportunity to carry out both in the same project provided a broad perspective of a research area that has been active since the pre-Apollo era.”

“Having the opportunity to carry out both in the same project provided a broad perspective of a research area that has been active since the pre-Apollo era.” - Dr. Dylan Hickson, Postdoctoral Researcher at Arecibo Observatory

Through their laboratory measurements, Dr. Hickson and his team showed that the dielectric models they tested could be effective at determining the permittivity of geologic powders; however, they found that some models are more accurate than others.

“Ultimately, my goal is to learn more about the complex surfaces of near-Earth asteroids,” Dr. Hickson shared. “Much more laboratory experimentation is needed to better understand the electromagnetic properties of these geologic materials.”

About Arecibo
The Arecibo Planetary Radar Program is funded by NASA’s Near-Earth Object Observations Program. The Arecibo Observatory is operated by the University of Central Florida (UCF) in partnership with Universidad Ana G. Mendez - Universidad Metropolitana and Yang Enterprises Inc., under a cooperative agreement with the National Science Foundation (NSF).

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Article written by Dr. Tracy Becker - AO Collaborator / SwRI Research Scientist Contact: tbecker@swri.edu Arecibo Media Contact Ricardo Correa Universidad Ana G. Mendez (UAGM) 787-878-2612 ext. 615 rcorrea@naic.edu

Head of Planetary Radar team Dr. Anne Virkki Arecibo Observatory avirkki@naic.edu

Keywords: arecibo, observatory, planetary, hickson, radar, scattering, rocks, space, models, Geophysical, Research, Planets, electromagnetic, properties, mineral, powders