posted on Dec, 19 2009 @ 06:02 PM
A daring proposal to try to put a "boat" down on a sea of Saturn's moon Titan is about to be submitted to Nasa.
The scientific team behind the idea is targeting Ligeia Mare, a vast body of liquid methane sited in the high north of Saturn's largest moon.
The concept will be suggested to the US space agency for one of its future mission opportunities that will test a novel power system.
It would be the first exploration of a planetary sea beyond Earth.
"It is something that would really capture the imagination," said Dr Ellen Stofan, from Proxemy Research, who leads the study team.
"The story of human exploration on Earth has been one of navigation and seafaring, and the idea that we could explore for the first time an
extraterrestrial sea I think would be mind-blowing for most people," she told BBC News.
Dr Stofan, who is also an honorary professor at University College London, has been describing her group's idea here at the American Geophysical
Union's (AGU) Fall Meeting, the world's largest annual gathering of Earth scientists.
The Cassini mission currently in orbit around Saturn has confirmed the haze-shrouded moon Titan to be an extraordinary place.
Great lakes exist on its surface, fed by rivers that wash down valleys whenever it rains.
In many respects, it resembles Earth and the way it cycles water between the surface and the atmosphere, except in the frigid temperatures of Titan it
is not water but liquid hydrocarbons that are in constant circulation.
Scientists got a few brief hours worth of data back from Titan's land surface in 2005 when the Huygens probe touched down in an equatorial region of
Now a number of those same researchers are desperate to go back for a longer-lived stay, but to investigate this time the huge pools that contain
methane, ethane, propane and probably many other types of hydrocarbon (carbon-rich) compounds.
The Titan Mare Explorer (TiME) has already been under study for about two years. It is envisaged as a relatively low-cost endeavour - in the low $400m
It could launch in January 2016, and make some flybys of Earth and Jupiter to pick up the gravitational energy it would need to head straight at the
Saturnian moon for a splash down in June 2023.
The scientists have a couple of seas in mind for their off-world maritime research vessel. Ligeia Mare and Kraken Mare are both about 500km across.
The primary objective of the mission would be to determine the precise chemistry of one of these lakes; but also to do meteorology, to help scientists
better understand how the "methane-ologic cycle" on Titan actually works.
"The key instrument is a mass spectrometer because you want to know what the lake is made of, but we also want to do things like depth-sounding,"
said Dr Stofan.
"We suspect from Cassini radar data that the lakes are many metres deep, but we'd love to know the overall shape of the lake basins.
"Other instruments would test different properties of the lake which would give you a handle on how the density of the liquid varied as the craft
According to team-member Dr Ralph Lorenz, what we learn from Titan's lakes could be relevant here on Earth.
It would give scientists the opportunity to study shared climate processes at work under very different conditions.
"If we have models that will work on Earth and on Titan then we can be much more confident that those models understand the fundamentals of what's
going on," explained the researcher from the Johns Hopkins University Applied Physics Laboratory.
"The photogenic appeal and the mystique of exploring a sea on another world speak for themselves, but there is a genuine practical application to do
with the science that will help us address problems here on Earth."