liquid (salty) water on Mars

Ohja et al have just published a paper reporting spectral evidence for
flowing (salty) water on Mars.

Pretty good news story:
http://www.nytimes.com/2015/09/29/sc...uid-water.html

Scientific paper (paywalled, but abstract & figures are open-access)
(I have not found an open-access preprint):
Ojha et al,
Nature Geoscience (2015) doi:10.1038/ngeo2546
"Spectral evidence for hydrated salts in recurring slope lineae on Mars"

Abstract:
Determining whether liquid water exists on the Martian surface is
central to understanding the hydrologic cycle and potential for
extant life on Mars. Recurring slope lineae, narrow streaks of low
reflectance compared to the surrounding terrain, appear and grow
incrementally in the downslope direction during warm seasons when
temperatures reach about 250--300 K, a pattern consistent with the
transient flow of a volatile species^1,2,3. Brine flows (or seeps)
have been proposed to explain the formation of recurring slope
lineae^1,2,3, yet no direct evidence for either liquid water or
hydrated salts has been found^4. Here we analyse spectral data from
the Compact Reconnaissance Imaging Spectrometer for Mars instrument
onboard the Mars Reconnaissance Orbiter from four different locations
where recurring slope lineae are present. We find evidence for
hydrated salts at all four locations in the seasons when recurring
slope lineae are most extensive, which suggests that the source of
hydration is recurring slope lineae activity. The hydrated salts
most consistent with the spectral absorption features we detect are
magnesium perchlorate, magnesium chlorate and sodium perchlorate.
Our findings strongly support the hypothesis that recurring slope
lineae form as a result of contemporary water activity on Mars.

--
-- "Jonathan Thornburg [remove -animal to reply]"
Dept of Astronomy & IUCSS, Indiana University, Bloomington, Indiana, USA
"There was of course no way of knowing whether you were being watched
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that they watched everybody all the time." -- George Orwell, "1984"