Pu-244, Iridium and the K-T boundery

i was watching a documentary on the Iridium line around the world and one of the people that said that if it were from a super nove there would be Pu-244


i thought long lasting isotopes of plutonium were man made

so my question being is, is there somehwere out in space some large conglomerate of polonium, plutonium etc?

I found a rock and it seemed to have the properties of irridium ore. I researched it long time ago. I have no idea where it went now, but if you hit it with a hammer, the hammer seemed to bounce back very strongly like it tossed the energy back at you.

The only element that seems to have that strange property is irridium, the rock was not pure metal either, it was like a piece of shale but extremely hard. I thought of taking it to the mine and have them figure out what it had in it. But the people I knew there left. So, I never got to check out if my assumption was correct.

originally posted by: penroc3
i was watching a documentary on the Iridium line around the world and one of the people that said that if it were from a super nove there would be Pu-244


i thought long lasting isotopes of plutonium were man made

so my question being is, is there somehwere out in space some large conglomerate of polonium, plutonium etc?

You sort of answered your own question, since supernovae produce Pu-244.
Given the age of the Earth being billions of years, the 80 million year half-life of Pu-244 is not long enough for a significant amount of it to have survived billions of years. So if we find any significant Pu-244 in rock strata, it probably came from a more recent supernova than the one which formed the Earth. However there have been some claims of Pu-244 measurements in trace amounts which were not confirmed in later, more precise attempts to duplicate the measurements.

The Pillars of creation in my avatar are about 7000 light years from Earth and have probably already been destroyed by a supernova in the neighborhood (we can't see the destruction yet due to the 7000 year lag in observation). So, that supernova remnant likely still has plenty of Pu-244, as do other supernova remnants which aren't that old compared to the 80 million year half-life of Pu-244.

a reply to: Arbitrageur

i wonder if there were enough nova close enough in distance and time that emitted enough Pu-39 for critical masses to come together.

i wonder if we could detect such explosions in space, or if anyone is looking for them.

heck just on the off chance that some civilizations chose to build the Orion spacecraft it might be good to look for them.

or places that in the future(a few 100 to 1000 year) we could farm for fuels or other very rare elements.

there have to be HUGE stores of stable elements in space.

a reply to: penroc3

i wonder if there were enough nova close enough in distance and time that emitted enough Pu-39 for critical masses to come together.

And greater amounts of other elements to mitigate chain reactions?
Not to mention that space itself is a pretty good mitigator. And there is no shortage of space, in space.

originally posted by: Phage
And there is no shortage of space, in space.

There's literally everything in space..

originally posted by: penroc3
a reply to: Arbitrageur

i wonder if there were enough nova close enough in distance and time that emitted enough Pu-39 for critical masses to come together.

You only really need one supernova's shock wave to trigger a gravitational collapse of a dust cloud which is a hypothesis for how our solar system may have formed. Once the remnant of the supernova and dust cloud collapses, then you can get a planet like Earth to form where some heavy elements can get close enough together to form a nuclear reactor like earth's Oklo natural nuclear reactor. A scientist hypothesized the moon might have formed from a natural nuclear reactor like Oklo that exploded though it's a "fringe" hypothesis since the Theia impact idea seems to be more popular, but he claimed it solved some problems with the Theia impact hypothesis, and could be tested by looking for traces on the moon, which might confirm or reject the hypothesis.

Did the Moon Form from a Nuclear Explosion?

i wonder if we could detect such explosions in space, or if anyone is looking for them.

Phage is right, space is vast and if you look at how the Little Boy nuke worked you can get some idea why that's a problem. It had a cylinder of U235 and a separate hollow cylinder of U235. They were both pretty dense, but it was the space between them and their low mass that kept them from going critical, until a firing mechanism brought them together. The dust in space is far less dense, so criticality is unlikely unless you get the conditions hypothesized in "Did the Moon Form from a Nuclear Explosion?" which required a dense rocky planet to form from the supernova remnant.

Could such an explosion be seen? With our current technology for detecting exoplanets, I'm not sure how we'd see it since what we actually detect is usually either the wobble in the star from the tug of the orbiting planet, or a dimming of the star when a planet eclipses it and I'm not sure either of those methods would reveal an explosion like the one hypothesized to form the moon.

there have to be HUGE stores of stable elements in space.

Did you mean to say unstable? You were talking about explosions, related to unstable elements, I thought?

The vast majority of the universe (~95%) is dark matter and dark energy and we don't know what those are. Of the remaining ~5% baryonic matter we understand, composition is about

73.9% Hydrogen
24.0% Helium
1.0% Oxygen
0.5% Carbon
0.5% Neon, Iron, Nitrogen, Silicon, Magnesium, and Sulfur

So, those 10 elements make up about 99.95% of the known baryonic composition of the universe, and all the other elements combined are only 0.05%. The fissionable elements are unstable, so whatever small portion they made up of the 0.05% has been decaying since the supernova that formed them, turning them largely into stable non-fissionable elements. So on a percentage basis at least, there's not that much fissionable material. Out of every billion atoms in the Earth's crust, only about 2 of them are Uranium according to current estimates, and I suspect that proportion would be lower in space where hydrogen and helium dominate the composition.

a reply to: Arbitrageur

im just playing devils advocate here obviously


out in the deep reaches of the universe there may have been a few BIG early stars that threw out some of the heavy radioactive elements in dust form.

now lets assume that for whatever reason the plutonium-244 'dust' started to coalesce like how the earths core was made but instead of iron and nickle it PU-244 and maybe some polonium to help with neutrons but as the now hot (in more then one way) is getting bigger and bigger compressing and heating our PU core mixed with other isotopes like polonium and whatever dusts that would contain lithium and hydrogen with all the normal planet building stuff acting as a moderator


but as the gravity squishes our planets core more and more neutrons hitting more atoms it would really start heating up.

granted this would be a very fast accretion of star ashes but it could happen.


i dont think it would blow up like nukes as we know them but iv seen rods being put into the spent fuel pool right out of the reactor and even with the crappy cam and odd lighting this rod looked more like a light saber then just some metal tubes and they took weeks for them to even be cool enough TEMP/RAD wise to move around in glove boxes

That natural reactor was in Africa that was assembled and moderated and refueled by nature, so i dont think my nuclear core planet is super crazy.

imagine if it was one of the furthest small snowball left for stuff to glob onto. And seeing as said snowball wouldn't have a sun anymore, what if the heat from a natural "RTG" to heat the planet from the inside out

a reply to: Arbitrageur

also thank you for a new moon theory

originally posted by: DaRAGE

originally posted by: Phage
And there is no shortage of space, in space.

There's literally everything in space..

cant wait for the last episode.........watch out for space snakes and Mortys's

originally posted by: penroc3
a reply to: Arbitrageur

also thank you for a new moon theory

You're welcome, but actually it's a hypothesis, and even the giant impactor idea is a hypothesis. "Theory" is reserved for something with lots of evidence to back it up, and the evidence for moon formation so far hasn't been completely convincing.

originally posted by: penroc3
now lets assume that for whatever reason the plutonium-244 'dust' started to coalesce like how the earths core was made but instead of iron and nickle it PU-244 and maybe some polonium...

I would need a reason to assume that.
The abundances of elements in supernova remnants vary as expected, but I don't see a reason why the PU-244 would segregate by itself like that. This is an elemental analysis of a supernova remnant and you can see there's more silicon than iron, but they are both pretty spread out as are the other elements, and mixed.

We Finally Know What Elements Are Contained in an Exploded Supernova

a reply to: Arbitrageur

if there were plutonium in the remnants just the fact its so dense i would think the heaviest of elements would come together first and as it passes in and out of the dust cloud it would collect the lighter more normal stuff.


not every planet would be a nickle/iron core, thankfully we live in a quite and relatively stable area in the outer part of the galaxy

i just want a nuclear heated planet....imagine the volcanoes, talk about fall out

a reply to: penroc3

i just want a nuclear heated planet

All you have to do is ask.

For all this, however, Marone says, the vast majority of the heat in Earth's interior—up to 90 percent—is fueled by the decaying of radioactive isotopes like Potassium 40, Uranium 238, 235, and Thorium 232 contained within the mantle.

phys.org...

a reply to: Phage

that is actually kind of scary, i hope we have enough isotopes to burn to keep the lights on so to speak.

ill have to look at the half lives of those isotopes but i wounder if the sun will go before our nuclear blanket

and what would happen if the nuclear heat just stopped(i know it cant just be shut off) one day, we would lose our magnetic shield once the dynamo freezes, then we turn into Mars.

ill have to look at some of Mars's geology but i always assumed it just was to small and something happened that froze its core...maybe it burned all its nuclear fuel or got a smaller amount of said heat fuel



yikes that article said basically the same thing, earth going cold and lifeless

a reply to: penroc3

You might even go ahead and read the article.

a reply to: Phage

i was reading it and it paints a bleak picture for future earth.


UNLESS

we get all the nuclear waste together and inject it into the mantle (obviously joking)

a reply to: penroc3

Sometime billions of years in the future, he predicts, the core and mantle could cool and solidify enough to meet the crust. If that happens, Earth will become a cold, dead planet like the moon.

One must filter consumer grade science. Note that there is no direct quote. The loss of mantle heat would not make the Earth cold. The vast majority of what keeps the surface warm comes from the Sun.

The bottom line is that, of the total heat reaching the surface of the Earth of (1.8+0.0000058) = 1.8000058 watts/cm^2, only 0.0000058/1.8 = 0.0003% is contributed by the Earth's internal heat. This, of course, will dominate everything else if the Sun were to magically vanish!

image.gsfc.nasa.gov...

And, unlike Mars, Earth probably has enough mass to keep its atmosphere even without a magnetic field to protect it from the solar wind. Venus has no such benefit, after all.

a reply to: Phage

i was under the impression that our magnetic field kept the solar winds at bay ?

a reply to: penroc3

Venus has no magnetic field and yet, it has an atmosphere.

The Venusians can thank gravity for that. An amount only 10% less than our own.

originally posted by: penroc3
yikes that article said basically the same thing, earth going cold and lifeless

The article is more or less right about heating from radioactivity, but I don't know why they made this comment which goes against mainstream science:

Sometime billions of years in the future, he predicts, the core and mantle could cool and solidify enough to meet the crust. If that happens, Earth will become a cold, dead planet like the moon.

Earth is far more likely to die in heat than in cold. We aren't sure exactly when but perhaps as soon as 1 billion years from now, Earth will already be so hot that we expect all the oceans to boil away, because the sun will be hotter by then (regardless if the core is cooler). And it will only get hotter and hotter "billions of years in the future" (not the core, the surface). If the Earth's orbit didn't get larger then it might even get swallowed by the sun (which will get so large it will extend past the orbit of Mars and swallow Mars) but Earth will probably avoid that fate because the Earth's orbit will likely be larger. They got their doom porn completely backwards! We'll still have some ice ages coming, like we've had before, but the ultimate death of life on Earth is far more likely to be a hot one than a cold one.

Will Earth's Oceans Boil Away? Yes—a billion years from now, as the sun gets brighter.

So if we want to colonize somewhere else, we better do it before all the oceans boil away, I don't see how we could survive that on Earth.