Project/Area Number |
17K05636
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Solid earth and planetary physics
|
Research Institution | Kobe University |
Principal Investigator |
Usui Fumihiko 神戸大学, 理学研究科, 特命助教 (30720669)
|
Co-Investigator(Kenkyū-buntansha) |
長谷川 直 国立研究開発法人宇宙航空研究開発機構, 宇宙科学研究所, 主任研究開発員 (10399553)
|
Project Period (FY) |
2017-04-01 – 2020-03-31
|
Project Status |
Completed (Fiscal Year 2019)
|
Budget Amount *help |
¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000)
Fiscal Year 2019: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2018: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2017: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
|
Keywords | 小惑星 / 含水鉱物 / 近赤外線分光観測 / 水・含水鉱物 |
Outline of Final Research Achievements |
Using the Japanese infrared satellite AKARI, we have detected the existence of water in the form of hydrated minerals in a number of asteroids for the first time. AKARI had the capability to obtain spectra at near-infrared wavelengths from 2 to 5 micron. Using this unique function, the spectroscopic observations of 66 asteroids were carried out. This provides the first opportunity to study the features of hydrated minerals in asteroids at around the wavelength of 2.7 micron. The observations detected absorption for 17 C-type asteroids. C-type asteroids, which appear dark at visible wavelengths, were believed to be rich in water and organic material, but the present observations with AKARI are the first to directly confirm the presence of hydrated minerals in these asteroids. This discovery will contribute to our understanding of the distribution of water in our solar system, the evolution of asteroids, and the origin of water on Earth.
|
Academic Significance and Societal Importance of the Research Achievements |
小惑星には含水鉱物として水が存在しているが、これを検出できる近赤外線の波長帯は地球大気の影響により地上の天文台からは観測できなかった。赤外線天文衛星「あかり」による観測で、数多くの小惑星について含水鉱物の存在を世界で初めて検出した。 「はやぶさ2」などの小惑星探査機と望遠鏡による天文観測は相補的であり、望遠鏡による多数の天体の網羅的な観測によって、探査機が詳しく調べた天体が一般的なのか例外的なのかという太陽系の中での位置付けを示すことができる。これにより、小惑星の起源と進化だけでなく、地球の水や生命の起源への理解も進むと期待される。
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