46
votes
What could make a planet more radioactive at night?
The ground worldwide might be rich in radioactive ores, but you have to dig at least half a mile down to find them.
However, many plants have roots that do go that far down. Those plants are ...
- 142k
41
votes
Accepted
Can a radioactive moon affect life on a planet?
How to generate radiation
Radiation by nuclear emission
A moon made of some non-fissile (definitely not fissile!) transuranic element would emit significant alpha, beta, and/or gamma radiation.
...
- 85.8k
40
votes
Accepted
Does it make sense to build a wall to protect a city from radioactive wasteland?
The wall is not for the radiation!
You can't keep out radiation with a wall. Plus the wasteland is only a little bit radioactive these days. Makes your hair curly. No, that wall is because you have ...
- 306k
36
votes
Using Polonium in a WMD
You do not. Unless...
This is not realistic.
However... see addendum for some hand-waving.
Ok, so Polonium-210 has a really high LD-50 value, that is all fine and well.
But where are you going to ...
- 44k
36
votes
Flashbang grenade that leaves a (radioactive) trace on people?
A similar trick was used by the KGB to track possible defectors: they would spread radioactive dust on their door mat, and would simply scan with a Geiger counter all the vehicles, looking for the one ...
- 301k
23
votes
What could make a planet more radioactive at night?
What if the planet doesn't become radioactive, but instead has a moon that is so radioactive that it will kill the colony as soon as it reaches a certain position in the (night) sky?
Assume it is ...
- 423
22
votes
Accepted
Why do every future relativistic spaceships have an atomic clock?
Atomic clocks do not use radioactive isotopes
Atomic clocks are not radioactive. They do not rely on atomic decay. Rather, they have an oscillating mass and a spring, just like ordinary clocks.
...
- 7,400
20
votes
Can a radioactive moon affect life on a planet?
I'm going to take this a slightly different direction and say that yes, radiation from a moon can indeed affect life on a planet, just not quite in the same way intended by the answer you linked.
As ...
- 8,249
19
votes
Accepted
What could make a planet more radioactive at night?
A highly radioactive gas that becomes much lighter when heated by the sun and rises to the top layers of the atmosphere or disperses into harmless levels.
I'm not sure if such a gas could exist and ...
- 314
19
votes
What evidence would there be if radioactive decay changed 7,000 years ago?
Tree ring sequences extend back further than 7000 years. A tree ring sequence for an area is derived from a series of pieces of wood whose growth periods overlapped.
C14 dating has to be calibrated ...
- 4,170
17
votes
What evidence would there be if radioactive decay changed 7,000 years ago?
Anthropologists and paleontologists are never happy with a single method of estimating the age of any item.
As has been mentioned there are tree rings. This leads to a large area of study called ...
- 9,601
16
votes
High energy density radioactive materials not commonly found on earth
Molot has the right answer, but I'd just like to chime in with numbers because that is what I do.
Chemical reactions
Chemical reactions don't release nuclear binding energy; instead they only ...
- 85.8k
16
votes
Flashbang grenade that leaves a (radioactive) trace on people?
How about something like SmartWater?
It's a well established technology that uses polymer chains or similar information encodable chemistry (a lot of the technology seems to be a trade secret) that ...
- 411
15
votes
What kind of hazardous alien waste would tear apart society trying to obtain it?
Metamaterials
The waste genuinely is just garbage.
The catch is that the civilisation that produced it does seriously cool things with material-science, and while most of their waste can be recycled, ...
- 11.8k
15
votes
Accepted
Effects of radioactivity several generations after exposure
It does not work that way, and it does work that way
The study of animals in the Chernobyl Exclusion Zone shows that being subjected to elevated levels of background radiation over time...
Fibroblasts ...
- 44k
14
votes
Flashbang grenade that leaves a (radioactive) trace on people?
I have two ideas. One is high-tech, and the other is low-tech.
1 Spray the protestors with a non-lethal substance that only shows up under blacklight.
Basically, the grenade would contain a certain ...
- 2,629
13
votes
Accepted
Radioactive weapon feasibility study
The problem is that with most weapons in the normal sense of the word the priority is to stop the enemy or render them ineffective rather than actually killing them. Indeed there is a school of ...
- 3,005
12
votes
What could make a planet more radioactive at night?
This solution is a bit extreme, but if your planet's solar system is doing something very exotic, you could get just that:
Have the entire solar system travel at relativistic speed through space
You ...
- 3,667
12
votes
Flashbang grenade that leaves a (radioactive) trace on people?
Taggants are already used or are proposed to be used in explosives. The idea is to leave behind traceable tags so the origin of the explosive can be traced. Some of these are are little microscopic ...
- 6,922
11
votes
Lead plate armor, a feasable defense against gamma radiation?
Not a lot. Yet a lot.
After quickly reading some articles I found that they use lead aprons to protect themselves during things like x-ray and such. They are about 7 to 14 kg (10-20 pounds), so not ...
- 40.2k
10
votes
Can a radioactive moon affect life on a planet?
Could it be radioactive enough to cause significant cancer increase, radiation sickness and mutations?
Not here, probably not elsewhere either
A radioactive moon could give out radiation in five ...
- 142k
10
votes
Accepted
Is there a good way to approximate alien biological age?
First, a note - radiocarbon is useful for determining age as it is meant in an archaeological sense, the time since a plant or animal died. (And often was made into some human artifact.) It is not ...
- 38.8k
10
votes
Accepted
What quantity of neutron radiation could a water-filled inflatable mattress functionally negate?
According to an article about "Neutron Shielding Materials", the half-thickness (thickness that absorbs half the radiation) of water against neutrons is 5.4 cm (page 8). 10 inches ~ 25 cm, ...
- 16.4k
10
votes
Lead plate armor, a feasable defense against gamma radiation?
Lets have a quick think about what sort of radioactive materials are likely to be long enough lived (given the 5000 year delay since the end of their production you mentioned in the older question) ...
- 78.5k
10
votes
Accepted
How would an invading force purposely put high levels of radiation on a planet?
The Earth-people took all of their things and detonated some sort of nuclear weapon (?), which devastated the population and changed the landscape.
In order to maintain a significant amount of ...
- 78.5k
9
votes
What could make a planet more radioactive at night?
Have a magnetic anomaly by which the planet's magnetic field almost completely disappears on the night side. During the day, the solar wind of high-energy protons is deflected by the planet and ...
9
votes
What evidence would there be if radioactive decay changed 7,000 years ago?
There are dozens of different radiometric dating methods available using a range of different isotopes
If the half-life of C-14 changed 7000 years ago Carbon would give dating results which were at ...
- 38.4k
9
votes
Accepted
Transporting radioactive fuels
Length contraction, like time dilation, is only seen by outside observers. To the crew, their spaceship & cargo, and their perception of time, will appear unchanged. It's only the outside ...
- 20.5k
9
votes
Why do every future relativistic spaceships have an atomic clock?
a doctrine which would have eliminated every traces of nuclear materials on the surface of Earth
The doctrine is plainly dumb and ill conceived.
There are no materials which are radiation free, and ...
- 301k
9
votes
Is it possible for a planet to have a noticeable portion of its atmosphere be radon gas?
What we know:
Planetary radius is 0.42 the Earth's:
Volume is 7.4% of Earth's;
Surface area is 17.6% of Earth's.
Mass is 0.17 Earth masses:
Average density is 2.3 times Earth's average density, or ...
- 98k
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