This sounds insane! I can't see these one-way trips ever catching on.

Honourable scientists in the past put their own lives on the line to prove their own convictions, but here we see the beginnings of a request for possible substitutes to indulge in scientific kamikaze. True honour exists outside of scientific circles. Life is risked in order to prove the scientists wrong.

They could send any kind of information from there and nobody on Earth could confirm or reject it for long time.

I'll go!!!

If they arrive at Jupiter and find a huge monolith floating in space, and it seems to be full of stars, they should get the hell out of there as fast as they can!
:-)

Sounds like a dead end job to me.

"Objective Europa appears to be purely self-sacrifice in the name of science."
Shouldn't this be 'self-sacrificial' as the phrase is being used as an adjective?

I can see the job advertisement: "Wanted intrepid, committed, individuals willing to risk it all to see the stars! Limited term employment good benefits! (In tiny print) Ridiculously poor retirement package."
Where they are going to find enough folks who are terminal cancer patients, geniuses, and suicidal all wrapped up in one is the more important question. Otherwise I fail to see how it could be ethical and practical.

Why Manned space craft? Why not robots like they do with the moon?

The most important thing about the first (or first several) mission(s) to Europa is to avoid contaminating it with Earth's microbes. This is very hard to do with sterilized hardware; it's beyond ridiculous with manned missions. How are you going to learn about (hypothetical) European microbes when you have already seeded the moon with thousands of species of human borne types?
Of course, that's only the start of the sundry objections to this silly idea.