An orbital water-ice cycle on comet 67P from colour changes

doi:10.1038/s41586-020-1960-2

GSTDTAP > 地球科学

DOI	10.1038/s41586-020-1960-2
	An orbital water-ice cycle on comet 67P from colour changes
	Oh, Myoung Hwan 1,2,3,4,5,6,7,8; Cho, Min Gee 1,2,3,7,8; Chung, Dong Young 1,2,3; Park, Inchul 1,9; Kwon, Youngwook Paul 10; Ophus, Colin 11; Kim, Dokyoon 1,2,3,12; Kim, Min Gyu 13; Jeong, Beomgyun 14; Gu, X. Wendy 15; Jo, Jinwoung 1,2,3; Yoo, Ji Mun 1,2,3; Hong, Jaeyoung 1,2,3; McMains, Sara 10; Kang, Kisuk 1,9; Sung, Yung-Eun 1,2,3; Alivisatos, A. Paul 4,5,6,7,8; Hyeon, Taeghwan 1,2,3
	2020
发表期刊	NATURE
ISSN	0028-0836
EISSN	1476-4687
出版年	2020
卷号	578 期号:7793 页码:49-+
文章类型	Article
语种	英语
国家	Italy; France; Germany
英文关键词	Solar heating of a cometary surface provides the energy necessary to sustain gaseous activity, through which dust is removed(1,2). In this dynamical environment, both the coma(3,4) and the nucleus(5,6) evolve during the orbit, changing their physical and compositional properties. The environment around an active nucleus is populated by dust grains with complex and variegated shapes(7), lifted and diffused by gases freed from the sublimation of surface ices(8,9). The visible colour of dust particles is highly variable: carbonaceous organic material-rich grains(10) appear red while magnesium silicate-rich(11,12) and water-ice-rich(13,14) grains appear blue, with some dependence on grain size distribution, viewing geometry, activity level and comet family type. We know that local colour changes are associated with grain size variations, such as in the bluer jets made of submicrometre grains on comet Hale-Bopp(15) or in the fragmented grains in the coma(16) of C/1999 S4 (LINEAR). Apart from grain size, composition also influences the coma' s colour response, because transparent volatiles can introduce a substantial blueing in scattered light, as observed in the dust particles ejected after the collision of the Deep Impact probe with comet 9P/Tempel 1(17). Here we report observations of two opposite seasonal colour cycles in the coma and on the surface of comet 67P/Churyumov-Gerasimenko through its perihelion passage(18). Spectral analysis indicates an enrichment of submicrometre grains made of organic material and amorphous carbon in the coma, causing reddening during the passage. At the same time, the progressive removal of dust from the nucleus causes the exposure of more pristine and bluish icy layers on the surface. Far from the Sun, we find that the abundance of water ice on the nucleus is reduced owing to redeposition of dust and dehydration of the surface layer while the coma becomes less red.
领域	地球科学 ; 气候变化 ; 资源环境
收录类别	SCI-E
WOS记录号	WOS:000529097800001
WOS关键词	IMAGING POLARIMETRY ; EVOLUTION MODEL ; 67P/CHURYUMOV-GERASIMENKO ; DUST ; GRAINS ; NUCLEUS ; SPECTROPHOTOMETRY ; SCATTERING ; OUTBURSTS
WOS类目	Multidisciplinary Sciences
WOS研究方向	Science & Technology - Other Topics
引用统计	被引频次：18[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/281205
专题	地球科学资源环境科学气候变化
作者单位	1.Inst for Basic Sci Korea, Ctr Nanoparticle Res, Seoul, South Korea; 2.Seoul Natl Univ, Sch Chem & Biol Engn, Seoul, South Korea; 3.Seoul Natl Univ, Inst Chem Proc, Seoul, South Korea; 4.Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA; 5.Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA; 6.Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA; 7.Univ Calif Berkeley, Kavli Energy NanoSci Inst, Berkeley, CA 94720 USA; 8.Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA; 9.Seoul Natl Univ, Res Inst Adv Mat, Dept Mat Sci & Engn, Seoul, South Korea; 10.Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA; 11.Lawrence Berkeley Natl Lab, Natl Ctr Electron Microscopy, Mol Foundry, Berkeley, CA USA; 12.Hanyang Univ, Dept Bionano Engn & Bionanotechnol, Ansan, South Korea; 13.Pohang Univ Sci & Technol, Beamline Res Div, Pohang Accelerator Lab, Pohang, South Korea; 14.Korea Basic Sci Inst, Adv Nano Surface Res Grp, Daejeon, South Korea; 15.Stanford Univ, Dept Mech Engn, Stanford, CA 94305 USA
推荐引用方式 GB/T 7714	Oh, Myoung Hwan,Cho, Min Gee,Chung, Dong Young,et al. An orbital water-ice cycle on comet 67P from colour changes[J]. NATURE,2020,578(7793):49-+.
APA	Oh, Myoung Hwan.,Cho, Min Gee.,Chung, Dong Young.,Park, Inchul.,Kwon, Youngwook Paul.,...&Hyeon, Taeghwan.(2020).An orbital water-ice cycle on comet 67P from colour changes.NATURE,578(7793),49-+.
MLA	Oh, Myoung Hwan,et al."An orbital water-ice cycle on comet 67P from colour changes".NATURE 578.7793(2020):49-+.