# s-astro: the thinning of an atmosphere to flash on track of sand

<< We think Mars had a thicker atmosphere in the past that might have formed smaller wind-drag ripples or even have prevented their formation altogether. Thus, the size of preserved wind-drag ripples, where found in Martian sandstones, may have recorded the thinning of the atmosphere >>

Guy  Webster, Robert  Perkins. NASA Rover's  Sand-Dune  Studies  Yield  Surprise. June 30,  2016.

http://www.jpl.nasa.gov/news/news.php?feature=6551

M. G. A. Lapotre, R. C. Ewing, et al. Large wind ripples on Mars: A record of atmospheric evolution. Science. 01 Jul 2016:Vol. 353, Issue 6294, pp. 55-58DOI: 10.1126/science.aaf3206

http://dx.doi.org/10.1126/science.aaf3206