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View Full Version : Better chance for life on Europa



ToSeek
2002-Oct-18, 03:35 AM
Thin ice opens lead for life on Europa (http://www.newscientist.com/news/news.jsp?id=ns99992929)

xriso
2002-Oct-18, 04:53 AM
Hmm... I had heard of research a while back that indicated the ice had to be at least tens of kilometres thick. It was something like they were looking at impact craters and seeing how thick the ice would have to be to not be broken by such a cratering event.

tusenfem
2002-Oct-18, 07:26 AM
Just plugging my own research /phpBB/images/smiles/icon_smile.gif
In our investigation of the magnetic field around Europa we found that it could be described mainly by the superposition of Jupiter's background field and an inductive magnetic field. The description of the inductive field I will skip but I will give the references below.
From our modeling of the magnetic field we found that the thickness of the ice should be around 10-20 km. However lately other investigations, e.g. of the ice have shown that the thickness of the ice could be as much as 30 km (sorry don't have the reference for that paper, lost it somewhere, will look for it).
Okay for some literature:
Kivelson et al: Galileo magnetometer measurements: A stronger case for a subsurface ocean, Science 289. 1340-1343, 2000.
Zimmer, Khurana & Kivelson, Subsurface oceans on Europa and Callisto: Constraints from Galileo magnetometer bservations, Icarus 147, 329, 2000.
I have these papers as pfd files, which will be uplinked to my webpage when I find the time. But I can send them by email. My email: DrMartinV@yahoo.com.
Greetings from Graz.

The Shade
2002-Oct-18, 06:46 PM
So, exactly how does that affect the Europa sub that's currently in the planning stages?

Is the ice the same thickness throughout the entire moon, or is it thinner at the cracks? (No jokes please)

John Kierein
2002-Oct-18, 08:10 PM
I thought the cycloid cracks in the surface from tidal motion implied a thinner ice crust.
http://pirlwww.lpl.arizona.edu/HIIPS/Publications/hoppa_abstracts/cycloid.html

Superstring
2002-Oct-19, 01:47 PM
This is quite convincing information. I have always suspected the icy layer is a thin one, though I never thought it would be thin enough to allow for sunlight to have an enhancing affect on possible microorgranic life. It is really looking like we have nearly all the ingredients for life on Europa: 1)high amount of liquid water, 2)sufficient heat source, in Europa's case internal and external, 3)organic material.

Now the bigger question is how long have these favorable conditions lasted on the moon? If it has only been like this for less than 1 billion year the chances of finding complex life forms are small. I will be researching this later on.