In 2017, we sent Cassini crashing into Saturn to avoid contamination
"The spacecraft will burn up and disintegrate like a meteor in the upper atmosphere of Saturn," Preston Dyches, of NASA's Jet Propulsion Laboratory (JPL), told Space.com via email. "This was determined to be the best way to ensure the safe disposal of the spacecraft, so that there would be no chance of future contamination of Enceladus by any hardy microbes that might have stowed away on board all these years."
Why was is not considered the same to that on a mission to the moon?
Tardigrades - often called water bears - are creatures under a millimetre long that can survive being heated to 150C and frozen to almost absolute zero.
They were travelling on an Israeli spacecraft that crash-landed on the moon in April.
And the co-founder of the organisation that put them there thinks they're almost definitely still alive.
and adds later
Even though the little moss piglets are likely to have survived the moon crash, it might not be great that they're there.
"What it means is the so-called 'pristine environment' of the moon has been broken," says Open University professor of planetary and space sciences Monica Grady.
When spacecraft leave Earth they are bound by the Outer Space Treaty not to contaminate their environment.
"I don't think anybody would have got permission to distribute dehydrated tardigrades over the surface of the moon. So it's not a good thing."
Is there some reason the Israelis decided to ignore the precedent? Or is it just not that important to protect the Moon from contamination anymore?