Spectral Evolution of Dark Asteroid Surfaces Induced by Space Weathering over a Decade
Name
Hasegawa_2022_ApJL_939_L9.pdf
Description
Published version
Size
1.69 MB
Format
Adobe PDF
Checksum (MD5)
fc7ccca75cd402f0f83ebf29c87bd962
Author(s)
Hasegawa, Sunao
DeMeo, Francesca E
Marsset, Michaël
Hanuš, Josef
Avdellidou, Chrysa
Delbo, Marco
Bus, Schelte J
Hanayama, Hidekazu
Horiuchi, Takashi
Takir, Driss
Date Issued
2022
Journal
The Astrophysical Journal Letters
Publisher
American Astronomical Society
Citation
Hasegawa, Sunao, DeMeo, Francesca E, Marsset, Michaël, Hanuš, Josef, Avdellidou, Chrysa et al. 2022. "Spectral Evolution of Dark Asteroid Surfaces Induced by Space Weathering over a Decade." The Astrophysical Journal Letters, 939 (1).
Version
Final published version
Abstract
Abstract
The surfaces of airless bodies like asteroids in the solar system are known to be affected by space weathering. Experiments simulating space weathering are essential for studying the effects of this process on meteorite samples, but the problem is that the time spent to reproduce space weathering in these experiments is billions of times shorter than the actual phenomenon. In 2010 December, the T-type asteroid 596 Scheila underwent a collision with an impactor a few tens of meters in size. A decade later, there is an opportunity to study how the surface layer of this asteroid is being altered by space weathering after the impact. To do so, we performed visible spectrophotometric and near-infrared spectroscopic observations of 596 Scheila. The acquired spectrum is consistent with those observed shortly after the 2010 impact event within the observational uncertainty range. This indicates that the surface color of dark asteroids is not noticeably changed by space weathering over a 10 yr period. This study is the first to investigate color changes due to space weathering on an actual asteroid surface in the solar system. Considering that fresh layers are regularly created on asteroid surfaces by collisions, we suggest a genetic link between D/T-type and dark (low albedo) X-complex asteroids and very red objects such as 269 Justitia, 732 Tjilaki, and 203 Pompeja. New observations show that 203 Pompeja has an X-type-like surface, with some local surface areas exhibiting a very red spectrum.
The surfaces of airless bodies like asteroids in the solar system are known to be affected by space weathering. Experiments simulating space weathering are essential for studying the effects of this process on meteorite samples, but the problem is that the time spent to reproduce space weathering in these experiments is billions of times shorter than the actual phenomenon. In 2010 December, the T-type asteroid 596 Scheila underwent a collision with an impactor a few tens of meters in size. A decade later, there is an opportunity to study how the surface layer of this asteroid is being altered by space weathering after the impact. To do so, we performed visible spectrophotometric and near-infrared spectroscopic observations of 596 Scheila. The acquired spectrum is consistent with those observed shortly after the 2010 impact event within the observational uncertainty range. This indicates that the surface color of dark asteroids is not noticeably changed by space weathering over a 10 yr period. This study is the first to investigate color changes due to space weathering on an actual asteroid surface in the solar system. Considering that fresh layers are regularly created on asteroid surfaces by collisions, we suggest a genetic link between D/T-type and dark (low albedo) X-complex asteroids and very red objects such as 269 Justitia, 732 Tjilaki, and 203 Pompeja. New observations show that 203 Pompeja has an X-type-like surface, with some local surface areas exhibiting a very red spectrum.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.3847/2041-8213/AC92E4
