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[Egan_BW]

In which case, (unless it decays SOO rapidly that containment is a very serious issue), casting it into a glass containment block, and using it as a radioactive heat source for space probes looks like a potentially beneficial way to get rid of it.   Not everything you would put an RTG into needs to have humans around it. (but yeah, electronics dont like high energy particle bombardment either.)

Using it in space kind of has problems. Presumably it would weigh more than whatever normally powers a nuclear plant, and in rocket launches that means that it's more expensive. I have no idea what the math actually looks like, but I'd guess that even if nuclear waste is way, way cheaper than actual fuel, using it would end up costing more in the end as you have to pay for the extra fuel to get it into orbit.
Of course there's the fact that rocket launches are hard enough as-is without also having to deal with literal deadly radioactive waste in the payload, and the fact that if your rocket happens to explode shortly after launch, as rockets sometimes do... congratulations, you just dirty bombed yourself!

[Bumber]

So, what's a little nuclear waste between friends?

What's up with those sensational article titles at the end?

Haley: U.S. Would Have ‘Totally’ Gone to War With N.K. if they launched a nuke at us first
Trump 2016 Election Win Linked to Voters Fearing Death rates and healthcare, because they're correlated to hopelessness

[Cthulhu]

This is a bit of a dumb question... and admittedly so.

I understand that things can be lethally radioactive without being thermally exciting. (say for instance, rapidly decaying gamma emitters, or highly bio-absorbed materials like radioactive iodines)  However, that does not sound like what is being discussed here. It sounds like they are discussing the crud left over from spent fuel rods, or the crud left over from centrifuging yellow cake uranium, and pals.  In those cases, the material emits radiation of kinds that ARE thermally exciting.

In which case, (unless it decays SOO rapidly that containment is a very serious issue), casting it into a glass containment block, and using it as a radioactive heat source for space probes looks like a potentially beneficial way to get rid of it.   Not everything you would put an RTG into needs to have humans around it. (but yeah, electronics dont like high energy particle bombardment either.)


As for the "I am TRUMP! I SMART! I save money by reclassifying glowing glass bricks the same way I classify dirty radioactive gloves, so I can just put it in a hole with some dirt on top!"  Yeah, that is pretty much what this appears to be.

did you hear about the electrical engineer who got kicked out of the speed dating session and arrested?

he experienced a singles event upset

In which case, (unless it decays SOO rapidly that containment is a very serious issue), casting it into a glass containment block, and using it as a radioactive heat source for space probes looks like a potentially beneficial way to get rid of it.   Not everything you would put an RTG into needs to have humans around it. (but yeah, electronics dont like high energy particle bombardment either.)

Using it in space kind of has problems. Presumably it would weigh more than whatever normally powers a nuclear plant, and in rocket launches that means that it's more expensive. I have no idea what the math actually looks like, but I'd guess that even if nuclear waste is way, way cheaper than actual fuel, using it would end up costing more in the end as you have to pay for the extra fuel to get it into orbit.
Of course there's the fact that rocket launches are hard enough as-is without also having to deal with literal deadly radioactive waste in the payload, and the fact that if your rocket happens to explode shortly after launch, as rockets sometimes do... congratulations, you just dirty bombed yourself!

It's been done before.  Cassini had a plutonium RTG and the launch vehicle was designed to eject the fuel before flight termination if it came to that.  It's been used on other spacecraft too, a lot of moon and mars probes.  I don't know if they also had modified flight termination.  Safety concerns add to cost but a long term power source without sunlight is very valuable too.

[Karnewarrior]

The thing is, sunlight is kind of plentiful in the solar system. The only new use I could see for a long-term low-power energy source beyond solar panels would be basically bootstrapping a camera to an ion engine and a load of Xenon and shooting it off into the depths of space forever more. Which the Voyager probes have already basically done.

[Trekkin]

It's been done before.  Cassini had a plutonium RTG and the launch vehicle was designed to eject the fuel before flight termination if it came to that.  It's been used on other spacecraft too, a lot of moon and mars probes.  I don't know if they also had modified flight termination.  Safety concerns add to cost but a long term power source without sunlight is very valuable too.

Key word there being plutonium, not whatever fuel stays in the raffinate; while Egan_BW is serendipitously correct in asserting that the power output per unit mass is much lower in waste, there's also a complex loss of fuel life, which compounds the mass problem by requiring large and ultimately unnecessary radiators to enable the requisite overload of fuel relative to mission requirements on launch.

In any event, the primary form of risk mitigation in RTG/RHU design has always been the fuel itself; ceramic plutonium doesn't easily shatter into dust, and the iridium coating the pellets serves to contain the fragments if they shatter. Those go into a graphite impact shell, as well. I've not seen any description of a separate eject system for the fuel. Do you have a source for that?

The thing is, sunlight is kind of plentiful in the solar system. The only new use I could see for a long-term low-power energy source beyond solar panels would be basically bootstrapping a camera to an ion engine and a load of Xenon and shooting it off into the depths of space forever more. Which the Voyager probes have already basically done.

Actually, it's not; as you go farther from the Sun, the power per unit area of solar panels decreases with the square of distance. It also requires that the panels face the Sun, which causes both guidance concerns (since you're essentially building a tiny solar sail and also need RCS to keep these big fragile things with a high moment of inertia oriented correctly) and worries about pitting and so forth reducing their effectiveness.

So yes, there's sunlight in space. That does not mean there's enough sunlight in space to power mission hardware that's accessible to a craft doing whatever it's doing, particularly in the outer solar system, let alone for long enough that the panels being blasted away isn't a big deal.

[bloop_bleep]

Plus ion drives are really not feasible for anything yet. The most powerful one we've built so far is able to produce a force of just 5 newtons. With Cassini's mass of 5712 kilograms at launch, that comes out to an acceleration of just around 0.0009 meters per second squared. That means from rest, in the absence of gravity, it would take 25 minutes for it to travel just one kilometer.

As we know, there is gravity within the solar system, and it's much stronger than 0.0009 meters per second squared. Maybe for interstellar voyages?

[Il Palazzo]

As we know, there is gravity within the solar system, and it's much stronger than 0.0009 meters per second squared. Maybe for interstellar voyages?

Luckily for all the ion thruster-equipped spaceships out there, that's not how orbital mechanics work.
Unluckily for this discussion, it has little to do with ameripol, eh?

[Trekkin]

As we know, there is gravity within the solar system, and it's much stronger than 0.0009 meters per second squared. Maybe for interstellar voyages?

Luckily for all the ion thruster-equipped spaceships out there, that's not how orbital mechanics work.
Unluckily for this discussion, it has little to do with ameripol, eh?

I was hoping he'd show us where we might find the rockets keeping the planets from falling into the Sun, but yes, until Trump actually creates his version of the Space Force it's only tangentially relevant except insofar as it continues to inform our policies on nuclear energy.

[smjjames]

Ok guys, let's take this one nice and slow and come to a conclusion ahead of time:

Should the USA be involved in Venezuela, and under what circumstances?

I know normally we just go in and bomb the shit out of everything, but I want to try something a little weird this time. We do NOT want a repeat of Somalia, where it was a bad idea to go, a bad idea to stay, AND a bad idea to leave.

I think you mean Iraq, not Somalia, though it’s more a combination of all our screw ups. Probably the only way we get militarily involved is when a South American nation decides to get involved (most likely Brazil, if past rumors were to go on) since South American countries would get pissed, though they’d probably still be pissed anyway.  At least that way, someone else gets left holding the metaphorical bag instead of us.

Anyways, Trump relented and said that he’ll do the State of the Union speech when the government reopens. https://thehill.com/homenews/administration/426717-trump-i-will-do-state-of-the-union-when-the-shutdown-is-over I guess he decided that he wasn’t willing to die on that particular metaphorical hill.

[Trekkin]

Anyways, Trump relented and said that he’ll do the State of the Union speech when the government reopens. https://thehill.com/homenews/administration/426717-trump-i-will-do-state-of-the-union-when-the-shutdown-is-over I guess he decided that he wasn’t willing to die on that particular metaphorical hill.

If he goes somewhere else, Pelosi wins forever. At least this way he can come back and congratulate himself to her face about how accommodating he's been. Calling what the other side is forcing you to do a mutual agreement is a transparent face-saving ploy, but by now he's probably more worried about losing MAGA hats than gaining anyone new, so why not?

Also, any other location would turn the State of the Union into a rally in all but name, and his addresses to the nation haven't moved the needle on the shutdown. He's losing ground, and every time he rides in to call it back and fails, that looks more and more permanent. What else can one do with an unpopular populist but remove him?

[wierd]

You know.. Some part of me wants to make and sell NAGA hats.

Not Again Godamit America!

[Trekkin]

You know.. Some part of me wants to make and sell NAGA hats.

Not Again Godamit America!

If you make tiny ones out of foam, filled in so people can adhere them to their pet snakes with peanut butter, you'll sell millions off the pun alone.

[wierd]

Vote for Team Reptile, autumn 2020!!

Why settle for anything less than real reptilian overlords?! Get your very own NAGA hat today!

[smjjames]

Trumps 1%er Cabinet strikes again.

https://www.cnn.com/2019/01/24/business/wilbur-ross-loans-food-assistance-government-shutdown/index.html

https://www.vox.com/2019/1/24/18195782/wilbur-ross-shutdown-workers-loans-food-banks

I can think of several reasons why they wouldn't want to take out loans...

[Kagus]

Oh man, that is... that is really something. It really, really is.