Goodbye Cassini, now part of the planet Saturn that it was studying

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I was hoping it would refuse the order to commit suicide.


Love to see similar focused missions to Uranus, Neptune, and Pluto.


I guess something about the zen of knowing you’re plunging to your death after a fulfilling life of outer-planet exploration just makes you want to paint a Rothko.


I have to say, I was a bit bugged by the idea that they slammed about 70 pounds of plutonium into the surface of a planet that hypothetically could have life.

I get that it almost certainly doesn’t, at least according to what we know about life. And also that the plutonium was in a form that was relatively inert.

Still. Just bugs me a bit.


Leave it be and run the risk of it hitting moons where a better chance at life would be, or crash it into a gas giant where it will get ripped apart in the atmosphere and not cause any issue (with a high chance of probability)

I would say they took the right approach. Plutonium or not.

Also: “surface of a planet”
This maybe a semantic thing, but can a gas giant have a surface?
I mean sure, go deep enough and the pressure of the gas is gonna be some kind of liquid but I doubt we should worry about anything we put there surviving upper levels to get that far.


I spent last night drunk on dinitrogen tetroxide and monomethylhydrazine trying to cope.


At more than 76,000 miles and hour, there won’t be much left to muss things up. Vaporized is the correct term for this kind of thing.


Hopefully it had a plaque that said it came from Mars…


Fast forward 30 or so years, the summer release of Star Trek Discovery: The Motion Picture. An alien entity calling itself C’Sni threatens earth and only one crew can save us all…


Those aren’t the only two options of course. They could have just let it wander into space. Or if it had to be disposed of, sent on an arc back towards the sun or towards a large meteor.

But again, I get that this isn’t a big problem. It just bugs me.

Wander into space? How does that happen when you’re in Saturn’s gravity well?


Vaporized would actually be the worst outcome if there was life. That means it could spread freely, and plutonium vapor would be incredibly poisonous to any life we understand.

Slingshot out again. Or don’t plan for it to get that close.

Again, I’m not saying this is a problem. I can understand wanting to get that close for scientific purposes, which is after all the point of the whole mission.

I’m just saying that slamming that much plutonium into a planet we don’t know that much about bugs me on a minor level, and I’m also pointing out that there are other options beyond smashing into Saturn or its moons.

Nope, it was only ever capable of crashing into Saturn, and had just the right amount of fuel to do that.

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Via the same mechanism that causes Saturnine biology to be affected by Plutonium vapors.


This. Mission planned to get the most data possible they would only have enough fuel to do a crash and burn. Leaving Saturn’s pull was never an option.

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People who launch space probes should be forced to take out insurance coverage against that sort of thing.

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I ᴅᴏɴ’ᴛ ᴏғᴛᴇɴ ɢᴇᴛ ᴛᴏ ᴄᴏᴍᴍᴜᴛᴇ ᴛʜɪs ғᴀʀ.


Saturn is a huge planet which already has a bunch of heavy elements inside it, left over from the formation of the solar system, no doubt including huge amounts of plutonium. The plutonium from Cassini will make no difference to Saturn at all.

What is important is that Cassini will not contaminate potential life forms on Titan and Enceladus. This mission has shown that there could well be living things orbiting Saturn, and protecting them from us is going to be a major focus for the remainder of this century.

There is no way to get Cassini away from Saturn. If you don’t get close to the planet you won’t learn about it. There is a huge salty, silty ocean inside a tiny little moon, spewing carbon compounds into space through geysers. That’s incredibly interesting and potentially a good look for us at both our past and our future.