Subsurface properties and early activity of comet 67P/Churyumov-Gerasimenko

作者：Gulkis Samuel^*; Allen Mark; von Allmen Paul; Beaudin Gerard; Biver Nicolas; Bockelee Morvan Dominique; Choukroun Mathieu; Crovisier Jacques; Davidsson Bjoern J R; Encrenaz Pierre; Encrenaz Therese; Frerking Margaret; Hartogh Paul; Hofstadter Mark; Ip Wing Huen; Janssen Michael; Jarchow Christopher; Keihm Stephen; Lee Seungwon; Lellouch Emmanuel; Leyrat Cedric; Rezac Ladislav; Schloerb F Peter; Spilker Thomas

来源：Science, 2015, 347(6220): aaa0709.

DOI：10.1126/science.aaa0709

Heat transport and ice sublimation in comets are interrelated processes reflecting properties acquired at the time of formation and during subsequent evolution. The Microwave Instrument on the Rosetta Orbiter (MIRO) acquired maps of the subsurface temperature of comet 67P/Churyumov-Gerasimenko, at 1.6 mm and 0.5 mm wavelengths, and spectra of water vapor. The total H2O production rate varied from 0.3 kg s(-1) in early June 2014 to 1.2 kg s(-1) in late August and showed periodic variations related to nucleus rotation and shape. Water outgassing was localized to the "neck" region of the comet. Subsurface temperatures showed seasonal and diurnal variations, which indicated that the submillimeter radiation originated at depths comparable to the diurnal thermal skin depth. A low thermal inertia (similar to 10 to 50 J K-1 m(-2) s(-0.5)), consistent with a thermally insulating powdered surface, is inferred.

• 出版日期2015-1-23
• 单位中央民族大学