And if it's Europa, why?

Correct me if I'm wrong here:

The big difficulty with a manned mission to Mars is either bringing enough reaction mass with you to blast back off of Mars and return to Earth (probably not feasible) or making more propellant once you reach Mars. (Probably feasible. Not holding my breath.)

Europa is covered with ice. We can make engines capable of using a substance like ice as reaction mass. (Nerva for example.)

Might a mission to Europa actually be easier to accomplish with existing technology?

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Anyone who believes in the warning of the bible (prophecies concerning the end time which is now) shall be benefited from my invention. Because they won't be stupid enough to pass this! -Alex Chiu

It would take about eight months to reach Mars, but a trip to Jupiter would take almost three years. Even if the problem of fuel for the return trip could be solved more easily on Europa, you're still looking at a mission lasting about five and a half years!

Hohmann Transfer in the Solar System

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- Learn a lot teaching others.

*wanders off muttering about Orion and stupid anti-nuke pressure groups* :wink:

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"Bessie Braddock to Churchill "Winston, your drunk!"
Churchill: "Bessie, you're ugly, and tomorrow morning I shall be sober""
the solar system

...and if we are talking about a manned mission to Europa...there's also the radiation question to consider. How are you going to protect the Astronauts??

Metaphasic shields.

Seriously though an Europa mission would be much harder than a Mars mission. Europa is located in the Jovian system which is very far away from Earth. Getting there and the return trip would be very long. Also there is intense radiation around Jupiter. Technology has to be developed to protect against it. Plus Jupiter's gravity well is very powerful. A strong propulsion system will be required to leave Jupiter's orbit.

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NCC 2000 - USS Excelsior. Commanded by captain Hikaru Sulu.