NASA considers which planets to visit

Ambitious plans to send probes to the outer planets are being considered by US and European space officials. One proposal envisages sending an orbiter to Saturn which would also drop a lander and a balloon on to the haze-shrouded moon Titan. The other sees two separate orbiters despatched to investigate Jupiter and its icy moons - Europa and Ganymede. Space agency officials will meet next week to decide which of the two plans should go forward for further study.

news.bbc.co.uk...

I cast my vote for Saturn and Titan, though Neptune and Uranus would be intrigueing...



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[edit on Wed Feb 18 2009 by Jbird]

reply to post by Grock


Considering recent discoveries such as Lake Vostok which is a pristine lake found buried under the bottom of the Antarctic ice sheet, this could prove that life can be sustained below the ice on Europa also. I think a mission to Europa to send a probe under the ice sheet would prove the most fruitful of all missions planned thus far.

[edit on 27/1/2009 by Kryties]

reply to post by Kryties


I agree that much could be gained by sending a probe to Europa but we must be carefull not to contaminate the place. NASA's track record has not exactly been stellar over the past 40 years and so I don't think that we can risk it until we can be 99% sure that we will not carry earthly microbes to Europa.

If you would like some examples of NASA mistakes here are a few.

Earthly microbes were carried to the Moon aboard the Surveyor 3 spacecraft. When the television camera from the lander was brought back by Apollo 12, the scientists discovered that the microbes were viable and were able to culture them. There was some debate for a short time that the microbes might have been native to the Moon. It was later determined that they were a common strain of streptococus that could not have evolved independently on the Moon.

Skylab and the Apollo/Soyuz projects accidently carried mosquitoes into space. In the case of the Apollo/Soyuz mission the mosquitoes survived a very intense sterilization process.

The Viking landers were possibly contaminated with microbes that resulted in false positive results for tests designed to detect Martian lifeforms. This is now being re-evaluated by NASA since methane and water have been detected on Mars. The truth is that NASA still does not know whether Viking was contaminated or not.

These are just a few examples of contamination of space vehicles. What would happen if one of these mistakes were made with a Europa probe? If we accidently contaminate Europa then that damage will be impossible to undo.

There was a BBC documentary made called "The Lost World of Lake Vostok". It talks about the exact contamination issues that you describe, and why they have yet to penetrate down into the lake until they figure out a way to do it without contamination from the Kerosine used in the drilling process, not to mention the microbial life most likely covering the drill. They reckon that if they can perfect a way to get a probe into the lake without contamination then they could do likewise for Europa.

But then again nothing is certain.

I had seen something online a few years ago about Lake Vostok as well. It's going to be very difficult to drill through the ice without contaminating the lake. Especially if they are going to use human labor to do the drilling. People are just covered in bacteria and they leave it everywhere.

If they are seriously considering the Lake Vostok project as an analog for exploration of Europa, then they need to ask themselves the question, "What happens if we fail and contaminate the lake?"

Who would trust them then, to successfully drill through the ice on Europa? What other site could they find on earth to practice?

In reality though, I think that the scientists who want to drill into Lake Vostok are just using the Europa story as a way to generate interest in their project. Without the sensational Europa analog, then it's just a bunch of guys who want to drill into a big lake under the ice in a very remote place. Not really the kind of story that makes the front page.

Still, I would hate to see the lake contaminated.

Maybe it's impossible to get into the oceans of Europa without contamination. Maybe it's all just a roll of the dice. If humanity was able to advance to the point of interplanetary space travel and had the capability of visiting, learning more and potentially colonizing planets or finding life on these other planets, BUT in doing so it would result in contamination of whichever places we visited, what would you do?

Not all contamination is bad, is it?

No, not all contamination is bad.

I have no problem with the microbes that we accidentally sent to the Moon. They really had no effect on the missions or on the Moon. No harm, no foul, in my opinion.

On the other hand, Earthly contamination could do huge damage to a planet with its own eco-system. It could also have a negative effect on our exploration attempts. A good case in point is Mars. If we find that Mars has microbial life, there will immediately be a debate among scientist about the possibility that the microbes originated on the Earth. This type of debate would last for years and in the end would damage the science, the space program, and the reputation of the scientists involved.

So, if we cannot drill through the ice of Europa, without contaminating the place, then we should hold off on doing it until we can do a better job.

reply to post by lunarminer


I see what you're saying and i've always been of that line of thought. But lately i'm considering the fact that I personally don't care if they discover microbes on Europa. What I care about is animals, you know? I want to see some LIFE, post haste my friend!

I mean, it's totally and completely ignorant on all counts to think that this is the only place life could begin. It seems like a big waste of time and effort to look for microbial life when all signs already point to yes. It's not going to change the world overnight if we find microbes on a distant planet, but it'll make a real splash if they find life, like you and me and my pet cat life.

Does that make sense?