In the search for life beyond Earth, few places beckon as strongly as Europa, an ocean-bearing, ice-covered moon circling Jupiter.
But how to pull off the mission, given today's tight science budgets and competing missions, such as a sample return from Mars?
A team of scientists may have the answer: Send a pair of landers directly to Europa and design the mission to last just seven days.
"When you're trying to design a mission to deal with the radiation environment (around Jupiter) one way to get around it is to have a lot of shielding and the other way is to not live very long," said Kevin Hand, an astrobiologist and planetary scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
Radiation shielding adds to a spacecraft's size and cost. The National Research Council's recently released study to prioritize planetary science for the next decade estimated a mission to Europa at $4.7 billion.
An alternative mission, unveiled at the American Geophysical Union (AGU) conference in San Francisco this month, would cut mission costs down to less than $1 billion.
It features a pair of landers that would launch in 2020 and fly directly to Europa to assess the moon's suitability for life. They would be designed to complete their missions within seven days -- enough time to measure the ocean, look for organics and photograph the surface features.
Europa is believed to have a global liquid ocean beneath its icy shell. New research shows Europa's ice and water might regularly mix, raising the prospect that traces of any ocean life could be found on the moon's surface.
"The best think you could probably do from the surface in a short time is to really nail down the composition of the non-ice material, particularly the organics," planetary scientist Paul Schenk, with the Lunar and Planetary Institute in Houston, told Discovery News.
"Selecting the right landing site is critical because you want material that's been recently exposed or been brought up from as far down as possible," Schenk said.
"I think you can go just about anywhere on the surface of Europa and do revolutionary science," Hand told Discovery News.
"Europa really does give us the opportunity to look for living life in the ocean that is there today and has been for much of the history of the solar system," he said.
The "Low-Radiation Europa Lander Mission Concept" is under review at NASA Headquarters.