A mission to Europa has long been on many people’s must-do wish list, and now NASA is taking another step closer to making that a reality. NASA has formally issued a Request for Information (RFI) to various science and engineering communities for ideas on how to design a mission to this exciting moon of Jupiter, which harbours an underground ocean that could possibly support life of some kind.
As John Grunsfeld, associate administrator for the NASA Science Mission Directorate in Washington explained, “This is an opportunity to hear from those creative teams that have ideas on how we can achieve the most science at minimum cost. Europa is one of the most interesting sites in our solar system in the search for life beyond Earth. The drive to explore Europa has stimulated not only scientific interest but also the ingenuity of engineers and scientists with innovative concepts.”
These concepts have been recommended by the National Research Council’s 2011 Planetary Science Decadal Survey for the study of Europa, with a deadline of May 30, 2014. It has become clear to both scientists and non-scientists alike that Europa should be a high-priority target for a dedicated mission.
Such a mission will not be cheap of course, but in these days of tight budgets, NASA is focusing on concepts that cost less than $1 billion (excluding the launch vehicle), yet still meet primary science priorities. The Europa Clipper is one concept which has received a lot of attention lately, using a probe to make repeated passes of Europa to study its internal structure instead of orbiting or landing. An orbiter or lander would be more exciting, but very expensive. But with the demand for a Europa mission growing, NASA is now attempting to achieve it, but for lesser cost, a not-so-easy balancing act. Congress has already appropriated $80 million for Fiscal Year 2014, with an additional $15 million for Fiscal Year 2015 budget proposal requests.
There are some key areas that need to be included in the proposals according to the Decadal Survey:
• Characterize the extent of the ocean and its relation to the deeper interior
• Characterize the ice shell and any subsurface water, including their heterogeneity, and the nature of surface-ice-ocean exchange
• Determine global surface, compositions and chemistry, especially as related to habitability
• Understand the formation of surface features, including sites of recent or current activity, identify and characterize candidate sites for future detailed exploration
• Understand Europa’s space environment and interaction with the magnetosphere.
Other more ambitious concepts have included drilling through the surface ice layer or even a robot submersible to explore the ocean, but those are still farther in the future. In December 2013 it was announced that the first evidence had been found for water vapour plumes on Europa, similar to those on Saturn’s moon Enceladus. It is possible that a probe like Europa Clipper could sample those plumes directly, like Cassini has done at Enceladus, which would be a much easier way to analyze the water coming from Europa’s interior.
This article was first published on SpaceFlight Insider.