資料載入中.....
|
請使用永久網址來引用或連結此文件:
https://ir.lib.ncu.edu.tw/handle/987654321/101999
|
| 題名: | The southern hemisphere of 67P/Churyumov-Gerasimenko: Analysis of the preperihelion size-frequency distribution of boulders ≥7 m |
| 作者: | 葉永烜;Pajola, Maurizio;Lucchetti, Alice;Vincent, Jean-Baptiste;Oklay, Nilda;El-Maarry, Mohamed R.;Bertini, Ivano;Naletto, Giampiero;Lazzarin, Monica;Massironi, Matteo;Sierks, Holger;Barbieri, Cesare;Lamy, Philippe;Rodrigo, Rafael;Koschny, Detlef;Rickman, Hans;Keller, Horst U.;Agarwal, Jessica;A’Hearn, Michael F.;Barucci, Maria A.;Bertaux, Jean-Loup;Boudreault, Steve;Cremonese, Gabriele;Deppo, Vania Da;Davidsson, Björn;Debei, Stefano;De Cecco, Mariolino;Deller, Jakob;Fornasier, Sonia;Fulle, Marco;Gicquel, Adeline;Groussin, Olivier;Gutierrez, Pedro J.;Güttler, Carsten;Hofmann, Marc;Höfner, Sebastian;Hviid, Stubbe F.;Ip, Wing-Huen;Jorda, Laurent;Knollenberg, Jörg;Kramm, J.-Rainer;Kührt, Ekkehard;Küppers, Michael;La Forgia, Fiorangela;Lara, Luisa M.;Lee, Jui-Chi;Lin, Zhong-Yi;Lopez Moreno, Jose J.;Marzari, Francesco;Michalik, Harald;Mottola, Stefano;Preusker, Frank;Scholten, Frank;Thomas, Nicholas;Toth, Imre;Tubiana, Cecilia |
| 貢獻者: | 理學院天文研究所 |
| 關鍵詞: | Astrophysics;Boulders;comets: general;comets: individual: 67P/Churyumov-Gerasimenko;Earth and Planetary Astrophysics;Equatorial regions;Erosion mechanisms;Erosion rate;Fracturing;Gravitation;methods: data analysis;Northern Hemisphere;Sciences of the Universe;Southern Hemisphere |
| 日期: | 2016-08-01 |
| 上傳時間: | 2026-04-21 14:55:31 (UTC+8) |
| 出版者: | EDP Sciences |
| 摘要: | 摘要： Aims. We calculate the size-frequency distribution of the boulders on the southern hemisphere of comet 67P Churyumov-Gerasimenko (67P), which was in shadow before the end of April 2015. We compare the new results with those derived from the northern hemisphere and equatorial regions of 67P, highlighting the possible physical processes that lead to these boulder size distributions. Methods. We used images acquired by the OSIRIS Narrow Angle Camera (NAC) on 2 May 2015 at a distance of 125 km from the nucleus. The scale of this dataset is 2.3 m/px; the high resolution of the images, coupled with the favorable observation phase angle of 62°, provided the possibility to unambiguously identify boulders ≥7 m on the surface of 67P and to manually extract them with the software ArcGIS. We derived the size-frequency distribution of the illuminated southern hemisphere. Results. We found a power-law index of −3.6 ± 0.2 for the boulders on the southern hemisphere with a diameter range of 7−35 m. The power-law index is equal to the one previously found on northern and equatorial regions of 67P, suggesting that similar boulder formation processes occur in both hemispheres. The power-law index is related to gravitational events triggered by sublimation and/or thermal fracturing causing regressive erosion. In addition, the presence of a larger number of boulders per km2 in the southern hemisphere, which is a factor of 3 higher with respect to the northern hemisphere, suggests that the southernmost terrains of 67P are affected by a stronger thermal fracturing and sublimating activity, hence possibly causing larger regressive erosion and gravitational events.
出版者： EDP Sciences
出版日期： 2016-08-01
出處： Astronomy and astrophysics (Berlin), 2016-08, Vol.592, p.L2
資源來源： EDP Sciences
版權： CC0 1.0 - Universal
識別號： ISSN: 0004-6361
識別號： ISSN: 1432-0746
識別號： EISSN: 1432-0746
識別號： DOI: 10.1051/0004-6361/201628887 |
| 顯示於類別: | [天文研究所] 期刊論文
|
文件中的檔案:
| 檔案 |
描述 |
大小 | 格式 | 瀏覽次數 |
|---|
| index.html | | 0Kb | HTML | 16 | 檢視/開啟 |
|
在NCUIR中所有的資料項目都受到原著作權保護.
|
