RocketSTEM Issue #13 - September 2016 | Page 70

Jupiter’s moon Europa has a crust made up of blocks, which are thought to have broken apart and ‘rafted’ into new positions, as shown in the image on the left. These features are the best geologic evidence to date that Europa may have had a subsurface ocean at some time in its past. Credit: NASA/JPL/University of Arizona around Jupiter, offering it numerous chances to perform up-close flybys past Europa. Th e team has planned for this to happen 45 times, at distances ranging from 1700 miles (2700 kilometers) to 16 miles (25 kilometers) away from the surface, so that the spacecraft can collect high-resolution images. The responsibility of project management will fall on NASA’s Jet Propulsion Laboratory, where a team has been collaborating with the John Hopkins University Applied Physics Laboratory (APL) to study the mission concept of the spacecraft taking multiple passes of the moon. Nine instruments have been chosen to hitch a ride on the satellite sent to Europa. Scientists will learn about the composition of the surface when cameras and spectrometers snap high-resolution photos and send them back for analysis. A radar will be utilized to penetrate the icy shell to measure its thickness and determine if lakes, comparable to those that reside underneath Antarctica’s ice sheet, exist underneath it. The strength and direction of Europa’s magnetic field will be measured by a magnetometer to figure out the depth and 68 68 salinity of the subsurface ocean. The mission will also observe the surface with a thermal instrument to look for recently erupted areas of warmer water. As a matter of fact, when I asked Dr. Niebur what part of the mission he is most looking forward to and if there is anything specific he would personally would like to know, he told me, “The idea of water lakes embedded in the ice shell near the surface is really fascinating to me. And I think that this mission will be able to find those if they exist. I also think in the future, when we do land and we do drill, it’s going to be the lakes that we target, because they are going to be closest to the surface and easiest to get to.” Other instruments on board will look for confirmation of water and small particles in the atmosphere of the moon. In 2012, the Hubble Space Telescope made a notable discovery of water vapor above the southern polar region of Europa, which could possibly be evidence of the existence of water plumes. If this is proven true, studying their composition could provide clues to the possibly life-sheltering environment’s chemical makeup, making it less www.RocketSTEM .org