Letters of Intent received in 2019

LoI 2021-2086
GA Focus Meeting:Planetary Astronomy from Macroscopic to Microscopic

Topics

• Surfaces on primordial solar system bodies
• Dust in the Solar System (e.g., comets, asteroids, interplanetary dust)
• Observation techniques (lander, microscope, polarimetry, optical, infrared, radio)
• Analyses of returned samples (Hayabusa, Hayabusa2, OSIRIS-REx)

Rationale

Celestial bodies which have not been reachable are now visited by spacecrafts and rovers, returned samples even touched by hands, and closely investigated with the aid of microscopes thanks to the advance of technologies. Accordingly, our research targets have downsized significantly over decades from kilometer to submicron, or even smaller. To cite just a few examples of the recent progress in astronomy and related fields, comprehensive ground-based surveys (e.g., Catalina Sky Survey) have discovered near-Earth asteroids down to ~1 meter during their closest approaches to Earth, cameras onboard spacecraft and lander (e.g., Hayabusa series ONC and MASCOT) took images of asteroid surface with ~1mm spatial resolution, and the Rosetta microscope revealed hierarchical aggregate structures of cometary dust particles down to ~0.1 um. Definitively, the wide coverage of size distributions and macroscopic information give hints for better understanding of planetary formation and evolution. In near future, it is scheduled that the Hayabusa2 spacecraft to bring the surface samples from the primordial asteroid Ryugu back to Earth. An effort to investigate the microstructure via remote-sensing observations is ongoing. Korean scientists are planning to conduct polarimetric mapping using the Wide-Angle Polarimetric Camera (Polcam) onboard Korea Pathfinder Lunar Orbiter (KPLO), which will be launched just one year after GA 2021. The main scope of this observation is to investigate ~10 um-scaled dust regolith on the lunar surface.

In this context, we propose to organize a meeting, where planetary astronomers who study targets with a wide range of sizes using various techniques gather together to exchange their information and recent findings, and to provide an opportunity to set future goals to be achieved in the coming decades.

This LoI for the GA Focus Meeting is supported by Prof. Gonzalo Tancredi, the President of Division F Planetary Systems and Astrobiology. In addition, Prof. Hyesung Kang, the Chair of the Organizing Committee of the IAU GA 2021, also willing to support this LoI.