Porous Alien Quicksand Could Doom Missions to Jupiter's Moon Europa
A new study explaining the negative polarization behavior on Jupiter's moon Europa suggests that its surface may be fine-grained particles with a void space greater than 95 percent. In other words—alien quicksand.
The grains would be about the wavelength of light, or a fractron of a micron, and less dense than fresh powder during a snowstorm. It also means that a potential lander on Europa could very well be swallowed up by the moon's surface.
"Of course, before the landing of the Luna 2 robotic spacecraft in 1959, there was concern that the Moon might be covered in low-density dust into which any future astronauts might sink," said lead study author and Planetary Science Institute Senior Scientist Robert Nelson. "However, we must keep in mind that remote visible-wavelength observations of objects like Europa are only probing the outermost microns of the surface."
Nelson's team used agoniometric photopolarimeter to study thirteen sorted particle size fractions of aluminum oxide. "The sample suite included particle sizes larger than, approximately equal to, and smaller than the wavelength of the incident monochromatic radiation," says the study's abstract. "The incident radiation has a very high probability of being multiply scattered before being backscattered toward the incident direction or ultimately absorbed."
The researchers believe that this is the optical arrangement that led to these findings is the first experimental demonstration of the Helmholtz Reciprocity Principle for polarized light. First proposed by Helmholtz in 1856, the principle explains how a ray of light and its reverse ray match reflections, refractions, and absorptions.
This research on the alien quicksand surface of Europa is especially fascinating when coupled with two studies from last year.
The first study suggests Europa's surface, like Earth's, undergoes a process of subduction, wherein one tectonic plate moves under the surface of another and sinks due to gravity. All told, the process suggests that Europa may have, or once have had, conditions suitable for sustaining life.
The second study details evidence that ice is swirling and forming on the surface of the moon. If ice is moving on Europa, this also means that water is flowing, at least near its equator. And we all know that water is a key building block of life.
NASA also plans to send a solar-power robot to Europa in a search for alien life. The robot will take pictures to build a detailed, comprehensive map of the moon, as current maps are undetailed and incomplete.
Of course, if all else fails, we could always just blow Europa up in order to uncover alien life--that's one hell of a way to make an introduction.