The last two sentences are not in the book, mind. They were added to the film version.

You could argue that the last two sentences were removed in the book version, since the book and film were written simultaneously and the book came out later.

No, the message is from 2010; the book was published in 1982 and the film, adapted from the book, in 1984.

You're thinking of _2001: A Space Odyssey_, which even though it was written simultaneously with the movie, had quite some deviations from it.

Now that you mention that...The mission will conclude with a crash on Ganymede. I guess from then on a bunch of Tardigrades will be the new population. Surprised they went with this decision.

> Surprised they went with this decision.

ESA explains it like this [1]:

> Category II missions are flyby or orbiter missions that venture to worlds where there may be some possibility of life, but the chances of contamination are slim. Then there's category III, where the chances of contamination are deemed greater.

> The planetary protection classification for Ganymede is driven by the likelihood that living organisms from Earth, brought to Ganymede by the spacecraft, can make their way down to the ice-ocean interface [...] In turn, this likelihood is deemed so low for Ganymede that it justifies a category II protection level, allowing for the spacecraft to be disposed on Ganymede's surface.

[1] https://www.space.com/europe-juice-jupiter-mission-planetary...

If tardigrades can survive launch, deep space, Jovian orbital conditions for years, and a crash on Ganymede, and then be able to reproduce, maybe they deserve to be there.

That is no problem for tardigrades.

"Tiny animals survive exposure to space" - https://www.esa.int/Science_Exploration/Human_and_Robotic_Ex...

Why would there be a bunch of tardigrades sitting on the probe? Unless they walk out to their nearest moss pile and smear it all over I think the chances are remarkably, incredibly slim.

You know they go to every length to sterilize the probe before launch?

Remarkably slim is not impossible.

Let me remind you of when we sent a probe to Earth, thinking it was sterile, and a few billions of years later our RNA-based lifeforms had spread everywhere.

Why do they sterilise it? Seems counter-intuitive.

Why is it counter-intuitive? If you send microbes to another planet, it's not possible to figure out if there were any before you arrived.

What, are you saying that it is expected that the probe will actually be inadvertently carrying Tardigrades that might actually survive to the surface? Hidden in little corners of the probe? Why didn't we sterilize it?

That is a bizarre decision. Have we learned nothing from the hundreds or thousands of examples of humans inadvertently messing with ecosystems by introducing new organisms?