D/H fractionation during sublimation of water ice at low temperatures into a vacuum. (1st September 2018)

• Record Type: Journal Article
• Authors: Mortimer, James; Lécuyer, Christophe; Fourel, François; Carpenter, James
• Is Part Of: Planetary and space science. Volume 158(2018)
• Page Start: 25
• Page End: 33
• Publication Date: 2018-09-01
• Subjects: Moon -- Sublimation -- Fractionation -- Water -- PROSPECT; Space sciences -- Periodicals; Atmosphere, Upper -- Periodicals; Sciences spatiales -- Périodiques; Haute atmosphère -- Périodiques; 523
• DOI: 10.1016/j.pss.2018.05.010
• Languages: English
• ISSNs: 0032-0633

Abstract

Abstract: The study outlined in this article was carried out within the framework of ESA's PROSPECT programme, which will provide both a sample drill and miniaturised mass spectrometer system for flight on-board the planned Russian Luna-27 mission to the lunar south pole. There, it aims to collect samples of regolith, containing water ice and other volatiles, and to make isotopic and abundance measurements to fingerprint the source(s) of these volatile species. However, it is necessary to first consider how any localised temperature increases during sample acquisition activities may result in water ice loss via sublimation and thus isotopic modification of the remaining residual ice. To attempt to address these concerns, a suite of sublimation experiments was conducted at the Laboratoire de Géologie de Lyon, where a method for performing such experiments was already established (Lécuyer et al., 2017). The results of this work will help to inform modelling which will extrapolate the data down to lunar-relevant conditions. Highlights: Sublimation rate at low temperatures is very slow, independent of pressure. 50% of the water ice can sublime before residual ice is significantly fractionated. Samples kept < -150 °C will not experience significant water ice loss for many hours.