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02-16-2020, 07:30 AM   #21
DataPacRat

Join Date: Nov 2004
Re: Any GURPS stats for black holes, pulsars, etc?

Quote:
 Originally Posted by Agemegos Let's see. 120 parsecs per hour is 4.22 × 10^14 metres per second, and the interstellar medium is around 50 000 000 molecules per cubic metre. Divide by Avogadro's number. Molar mass of hydrogen is two grams. 0.000 07 kg/m²/s. ½mv² = 6.23 × 10^24 watts per square metre. Frontal area of a speedster would be a bit over six square metres. Call that, say, four by ten to the twenty-fifth power joules per second. Spaceships beam damage table. Treat as a neutral particle beam. Four by ten to the nineteenth MJ. Nineteen powers of ten from 3 MJ => nineteen doublings from 3 dice decadal damage. Three million d6 of damage going "dink!" every second.
Let's see; in the local interstellar medium, a speedster can actually hit 450 parsecs/hour instead of 120, so let's multiply that figure by (450/120)^2=14.0625; and multiply it by 10 to convert from decade-scale damage to regular damage; and divide by 100 because the ship is "free" with its Bergenholm active. That works out to an average damage of 14.7M per second... just a hair under half of what the wall-shield provides, meaning said wall-shield doesn't even gain an energy-level when cruising along.

... I think we just discovered how GURPS Lensmans' writers decided how much shielding to put on that speedster. :)

Quote:
 Originally Posted by whswhs Well, an HP. It doesn't have an ST, having no musculature or comparable structures, and its telekinetic ST could be anything. Though I suppose you could estimate it from the force needed to escape from it (if you weren't inside the event horizon).
A possible line of attack: a magnetic field of 16 Tesla is strong enough to levitate a frog (or, presumably, any other organic matter that's subjected to such a field). A 10-15 km radius neutron star's magnetic field, at its surface, is between 10^4 and 10^11 Tesla (with magnetars being 10^8 and 10^11). Making the somewhat unwarranted assumption that the inverse square law applies, then at 242,000 km out (as close as it's safe for the speedster to approach, considering only gravity), then the field would be somewhere around 1/((242,000/10)^2) to 1/((242,000/15)^2) = 1/585,640,000 to 1/260,284,444 as strong, let's say 1/500M. Which would make the magnetic field at that distance 0.00002 to 200 Tesla. Which, making a further unwarranted assumption about diamagnetism, is a force somewhere between 'unnoticeable' and 'exerts 12.5 gravities of acceleration'.

Which looks like I should multiply the minimum safe distance around magnetars by around a factor of, say, four or five.
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