A1 Refereed original research article in a scientific journal
Evidence of sub-surface energy storage in comet 67P from the outburst of 2016 July 03
Authors: Agarwal J., Della Corte V., Feldman P., Geiger B., Merouane S., Bertini I., Bodewits D., Fornasier S., Grün E., Hasselmann P., Hilchenbach M., Höfner S., Ivanovski S., Kolokolova L., Pajola M., Rotundi A., Sierks H., Steffl A., Thomas N., A'Hearn M., Barbieri C., Barucci M., Bertaux J., Boudreault S., Cremonese G., Da Deppo V., Davidsson B., Debei S., De Cecco M., Deller J., Feaga L., Fischer H., Fulle M., Gicquel A., Groussin O., Güttler C., Gutiérrez P., Hofmann M., Hornung K., Hviid S., Ip W., Jorda L., Keller H., Kissel J., Knollenberg J., Koch A., Koschny D., Kramm J., Kührt E., Küppers M., Lamy P., Langevin Y., Lara L., Lazzarin M., Lin Z., Lopez Moreno J., Lowry S., Marzari F., Mottola S., Naletto G., Oklay N., Wm. Parker J., Rodrigo R., Rynö J., Shi X., Stenzel O., Tubiana C., Vincent J., Weaver H., Zaprudin B.
Publisher: Oxford University Press
Publication year: 2017
Journal:: Monthly Notices of the Royal Astronomical Society
Journal name in source: Monthly Notices of the Royal Astronomical Society
Volume: 469
First page : S606
Last page: S625
Number of pages: 20
ISSN: 0035-8711
DOI: https://doi.org/10.1093/mnras/stx2386
On 2016 July 03, several instruments onboard ESA’s Rosetta spacecraft detected signs of an
outburst event on comet 67P, at a heliocentric distance of 3.32 au from the Sun, outbound
from perihelion. We here report on the inferred properties of the ejected dust and the surface
change at the site of the outburst. The activity coincided with the local sunrise and continued
over a time interval of 14–68 min. It left a 10-m-sized icy patch on the surface. The ejected
material comprised refractory grains of several hundred microns in size, and sub-micron-sized
water ice grains. The high dust mass production rate is incompatible with the free sublimation
of crystalline water ice under solar illumination as the only acceleration process. Additional
energy stored near the surface must have increased the gas density. We suggest a pressurized
sub-surface gas reservoir, or the crystallization of amorphous water ice as possible causes.
