There seems to be a bunch of misunderstandings regarding the findings of the paper, and there is also is an issue with unit terminology when translating rem to Aurora-radiation. Both of those are pretty seriously impairing the validity of the idea I fear. Sorry to be the bearer of bad news, but I have to state this nonetheless.
-> Let's start with the terminology of
Aurora radiation, since clearing this up will be foundational for thinking about the rest:
At that point I require a conversion from real world radiation into Aurora radiation. Line 10 shows this as Aurora Radiation = Rems x 100. In general, 500 rems will kill 50% of the affected population within a month and 1000 rems will kills 90% in a week. If Aurora Radiation (AR) = 100x Rem, then 500 rems = 50,000 AR, which is -500% production and -125% growth. If AR was lower, say 10x Rem, that would be -50% production and -12.5% growth, which doesn't seem to reflect the severity of that amount of radiation.
The paper states that the energy of 10^47 ergs is delivered over the span of a couple weeks, so it doesn't come all at once, and subsides completely after. From the presented idea frame, I could not read out how this was supposed be handled. It could be that, -let's assume 5 weeks-, the radiation could be delivered in 7 separate accumulating doses for example, but that could be a very wrong interpretation of how Aurora radiation works. Essentially you'd be trying to represent the dna-damage that all the inhabitants received by some other properties equivalence.
To clarify, Aurora radiation obviously has some sort of lingering effect to it, which seems to summon more the image of poisonous still irradiated material lying or flying around everywhere. One could attempt to argue that the continued decimation after the event might simply be the incredible cancer incidence that follows after, and though this sounds good at the start, one still would have to explain how you could ship fresh colonists from somewhere else, which will then immediately begin suffering the planet's same radiation effects. ..The irradiating event that caused all of this harm has already vanished, so why would new colonists be afflicted by anything.(the afterquake ionization effect should be nowhere on the scale of decimation that would befall everyone if the radiation wasn't removed)
The big problem is that Aurora radiation really leaves no way to accommodate the supernova 'one-time-radiation-dose' type effect. ..Because you could for example try, let's say to have the intense radiation for 7 construction cycles at about 1/7th of the calculated total local intensity each, and then return to 0 radiation. ..But now it is the lingering cancer effects and such that aren't accommodated for.
So translating rem into Aurora radiation is essentially like trying to equate something like "how many 'stubbing your toes on furniture' until = 1x'news of the dog getting hurt'". It should be clear that the 1rem=100Arad is not an exact formula, but an attempt to equate the two by projection of their similar properties.
One way or the other, there are corners to be cut and aspects to be dropped, because Aurora radiation does not operate on the physical basis of SI-units, but is an abstracted value that essentially means "radiation consequences", not dosage, or energy directly, so there are shortcomings in what it can simulate.
Btw. the doses are also insane in the calculation. Nearly 1 million rem at 100Lys even with atmosphere? I looked up the health effects of such dosage, and apparently the cancer risk scales lineraly by 0.055% per rem, so that would be 55,000% more cancer risk. Yet in Aurora that is only -25% growth per year too, while any human experiencing something like this would be toast a hundred times over wayyy before cancer even becomes relevant.
..Yeah, given that the paper also cites there are 1-2 supernovae in the milky way per century, and it is barely 100,000lys across, it is safe to say that for life to still be here, there must be some error in the math, and there is, which brings me to the second critical point.
-> The findings of
the paper:
The above paper discusses the protection afforded by Earth's atmosphere and (for marine life) the oceans. In short, that protection is significant. For gameplay purposes, I am planning to divide the radiation impact by 1 for evert 0.01 atm - or by 100 for 1 atm (shown on line 11 - line 12 was an alternative view). This is considerably underselling the protection in reality, but it makes things a little more interesting.
The word "significant" here can not be understated, for the effect is the difference between a camera flash or looking into the sun without any protection. As the paper describes tangentially in Table 1, but mostly in Table 2, even the most apocalyptic assumption, -which is all supernova energy being 'somehow' discharged as natures most penetrating photonic 50meV radiation-, still is reduced by a factor of nearly 10^8 after passing through our atmosphere.
..Maybe describing the Attentuation Coefficient from Table 2 is in order. The calculation to (somewhat) get the numbers you see there out of the coefficients cited in the header is:
^d)
..where d is the distance the radiation has to travel through the medium in centimeters.
(in regards to water. air turns out to be more complex [see below] and is cited here as "1000cm water equivalent", which is sometimes done)You can quickly check this by using the attentuation coefficient of water for 50meV of 0.0167 like this:
^{10}&space;=&space;1.5379E^{-32})
or
^{100}&space;=&space;3.378E^{-33})
..to find this as the result of 10 cm and 1m water radiation reduction respectively.
(The paper link again for convenience: https://www.irpa.net/irpa10/cdrom/00063.pdf)Now, it is important to note that the result diverges more the deeper you go (the 100cm number is already a few percent of to what was quoted for example), which happens because it is not actually important how much distance the radiation travels through the material, but how much
matter of the material it really travels through. Since there is of course a density gradient throughout, the real calculation is more involved, and it is why the units in the header are actually given in a shape that cites mass instead of just distance.
So while you can also do the calculation with the air density like this:
^{1000}&space;=&space;0.089Gray)
..the result is obviously overstated by a factor of 8 from the quotes 0.0102 here already. The real result would instead be by about ^1133 or so, which is taking into account the shifts of density.
Now, the next point. Also cited in the paper is that most supernovae deposit their photonic energy in forms of a few hundred keV, which even at the peak range are absorbed much more quickly as also stated in Table 2. If you started with a 'top-of-atmoshere' incredibly high 1,000,000 Gray dose, the amount of radiation of such a more realistically emitting supernova that would even reach the ground drops to 1.8x10^-32, which is not even enough to reheat the thoughts of one's first lost love. Note that for the initial dose to even be that high, the supernova would need to be nearer than 1 parsec (see Table 1), which is closer than the closest star to Earth.
Ahem, so again, it really pains me to be the bearer of bad news, since this was a good idea for a new catastrophy event, and I
do like more stuff like this or other space curiosities be added to Aurora. So I didn't want to dim their shine, but it is as it is, and deadly glaring supernovae simply don't exist as long as you are on ground. Their lights are literally just Christmas decoration.
///Gamma-ray bursts though. Yes, a whole other league and the few more mysterious extinction events are actually hypothesized to come from those, not supernovae as the paper claims.
Also, I find it interesting that the paper observes that ideas of Panspermia are much reduced in likelihood due to supernovae acting as an astral sanitizing agent.(because the radiation still hits hard without good shields) I had never thought of that.///Edit: Here a picture that shows which parts of the spectrum make it through the atmosphere. It would take extremely brute force to be able to overpower this near 100% shade effect we luckily have going for us.
