NASA has announced that it has selected nine science instruments for a mission to Europa, one of Jupiter’s 67 moons, to see if it could harbor conditions suitable for life. The space agency’s Galileo mission provided evidence that Europa has an ocean beneath a frozen crust of unknown thickness. If true, this global ocean could have more than twice as much water as Earth. Europa — a little smaller than Earth’s moon — might be the best place in the solar system to look for present-day life, thanks to its salt water, rocky sea floor, and the energy and chemistry provided by tidal heating.
NASA’s has requested $30 million in its fiscal year 2016 budget request for a mission to Europa. According to the NASA website, “the mission would send a solar-powered spacecraft into a long, looping orbit around the gas giant Jupiter to perform repeated close flybys of Europa over a three-year period. In total, the mission would perform 45 flybys at altitudes ranging from 16 miles to 1,700 miles.”
The nine selected science instruments include cameras and spectrometers to produce high-resolution images of Europa’s surface, in order to determine its composition. An ice-penetrating radar will verify the thickness of Europa’s icy shell and search for subsurface lakes (similar to those beneath Antarctica). A magnetometer will measure the strength and direction of the moon’s magnetic field, allowing scientists to determine the depth and salinity of the ocean. A thermal instrument will search the surface for recent eruptions of warmer water. Other instruments will seek evidence of water and tiny particles in the atmosphere.
NASA has selected nine proposals for instruments to study Europa, which includes several experts from the Jet Propulsion Laboratory in Pasadena, Calif. The JPL is home to the Spacecraft Assembly Facility, a Class 10,000 ISO 7 cleanroom with horizontal airflow and return. Also, the SPace Environmental and Composition Investigation near the Europan Surface (SPECIES) instrument will be utilized. The NASA website states, “Led by principal investigator Dr. Mehdi Benna at NASA’s Goddard Space Flight Center in Greenbelt, Md., this combined neutral mass spectrometer and gas chromatograph will be developed for other mission opportunities.” The Goddard Space Flight Center is home to a Class 10,000 cleanroom.
Read more — Cleanroom Snapshot: Cleaning Space Mirrors with CO2 Snow: http://www.cemag.us/blogs/2015/05/cleanroom-snapshot-cleaning-space-mirrors-co2-snow
In other NASA news, NASA’s Mars Curiosity rover detected an unexplained methane spike on Mars in 2014. The Curiosity rover was built and tested in the cleanroom at the JPL.
“This temporary increase in methane — sharply up and then back down — tells us there must be some relatively localized source,” said Sushil Atreya of the University of Michigan, Ann Arbor, and Curiosity rover science team, in a December 2014 news release from NASA. “There are many possible sources, biological or non-biological, such as interaction of water and rock.”
Science World Report notes that the cause of this sudden “burp” is currently being debated. The article quotes Kevin Zahnle from the Ames Research Center as saying, “I am convinced that they really are seeing methane. But I’m thinking that it has to be coming from the rover” during a seminar hosted by the NASA Astrobiology Institute’s Virtual Planetary Lab.
However, the article also quotes Chris Webster, a senior research scientist at NASA’s Jet Propulsion Laboratory and lead author of a study published in Science. “We are continuously monitoring that methane amount and there hasn’t been evidence of any leakage during the entire mission,” said Webster “And while it’s true that the concentration of methane in that chamber is 1,000 times higher than in Mars’s atmosphere, the comparison is actually misleading. You have to look at the amount of methane, not the concentration. The concentration of methane on the rover may seem high, but the actual amount is very small because the chamber is very small. To produce the amount we detected in Mars’s atmosphere, you’d need a gas bottle of pure methane leaking from the rover. And we simply don’t have it.”
NASA has acknowledged that the Curiosity rover could indeed be the cause of the methane spike. Other theories presented by scientists include a seasonal phenomenon on Mars, or a meteorite falling within the rover’s vicinity. The European Space Agency, in conjunction with space agency Roscosmos, plans to send its ExoMars Trace Gas Orbiter to the red planet to gain a better understanding of methane and other atmospheric gases that are present in small concentrations. It will be launched in January 2016 and should reach Mars in October.