Headline o’ the day: “Brazil Nut Effect Measured in Lunar and Martian Gravity Conditions”

Today’s Headline of the Day appears in The Physics arXiv Blog:

Brazil Nut Effect Measured in Lunar and Martian Gravity Conditions

The headline concerns the also-intriguingly-headlined study

Granular convection and the Brazil nut effect in reduced gravity,” Carsten Güttler [pictured here], Ingo von Borstel, Rainer Schräpler, Jürgen Blum,” arXiv:1304.0569, Apr 2, 2013. The authors report:

guettler_155px“We present laboratory experiments of a vertically vibrated granular medium consisting of 1 mm diameter glass beads with embedded 8 mm diameter intruder glass beads. The experiments were performed in the laboratory as well as in a parabolic flight under reduced-gravity conditions (on Martian and Lunar gravity levels). We measured the mean rise velocity of the large glass beads and present its dependence on the fill height of the sample containers, the excitation acceleration, and the ambient gravity level. We find that the rise velocity scales in the same manner for all three gravity regimes and roughly linearly with gravity.”

(Thanks to investigator Peppe Liberti for bringing it to our attention.)