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User:GiverOfThePeace/Standard Calculation for Meteors, Comets, etcetera
Introduction
Meteor, Comet, etcetera calculations.
Meteor
Meteors sizes are some of the hardest to find since they're very small ass rocks.
We'll use the smallest one found here: https://sites.wustl.edu/meteoritesite/items/how-big-are-meteorites/
Which is Morito. About 10.1 tons or 9162.566 kg
For warning it's noted these sizes exaggerate the size of a meteor so this is the safest low end to use.
https://www.amsmeteors.org/meteor-showers/meteor-faq/ Meteors are stated to move from 11000 m/s
Since the size itself is admitted to be exaggerated we'll be using the lowest end of the meteor's speed
KE = 0.5mv^2 = 0.5(9162.566)(11000)^2 = 5.079133250113500e15 J
Now we need to take inverse square law into account:
Meteorites are stupidly small being a diameter of 1 meter at their largest. Making the surface area 12.57 meters^2
The CA would be half of that which is 6.285 m^2
And the surface area of a fist is 0.43 m^2 according to google
6.285/0.43 = 14.6162790697674419
5.079133250113500e15 J / 14.6162790697674419 = 3.475e14 J or 83.054 Kilotons of Tnt, aka 7-C.
Comets
Comets travel at 2000 miles per hour when far away from the sun: https://www.mrsd.org/cms/lib/NH01912397/Centricity/Domain/245/comets.pdf
https://en.wikipedia.org/wiki/Comet Comets have an average density of 0.6 g/cm^3
A comet that’s 5 km in radius is assumed to have a volume of 5 * 10^17 cm^3: https://www.vanderbilt.edu/AnS/physics/astrocourses/ast201/comets.html#:~:text=But%20the%20typical%20comet%20is,the%20mass%20of%20a%20comet%3F&text=M%20%3D%20density%20x%20volume%20%3D%20(,the%20inner%20solar%20system%20…
Multiply volume and density together and you get 300,000,000,000,000 kg.
KE = 0.5mv^2 = 0.5(300,000,000,000,000)(894.08)^2 = 1.99845E+20 Joules or Island level, but we're not done yet.
Now we need to take inverse square law into account:
Using the 5000 meter radius and assuming the comet is a sphere, the surface area would be 3.14 * 10^8 m^2
Thus the CA would be half of that at 1.57 * 10^8 m^2
And the surface area of a fist is 0.43 m^2 according to google
So take (1.57 * 10^8) / 0.43 to get 365116279.07
1.99845E+20 J / 365116279.07 = 5.47346178 × 10^11 joules or 130.81 Tons of TNT. Which is 8-A
Asteroid
Asteroids kind of varies greatly in size: https://nssdc.gsfc.nasa.gov/planetary/factsheet/asteroidfact.html
So we'll be taking the lowest end for safety which is listed as Itokawa.
35,000,000,000 kg
This asteroid goes a distance of 0.9 to 1.7 AU in 18 months which means it moves at 5,376.3 m/s.
Same thing as before.
KE = 0.5mv^2 = 0.5(35000000000 kg)(5376.3)^2 = 1.7704068535125e28 J or 4.2313739328692641095 exatons, again we're not done here.
Itokawa's radius is 156.5 meters, assuming this as a sphere, the surface area would be 307,778.69 m^2
CA is half of that so 153889.345 m^2
And the surface area of a fist is 0.43 m^2 according to google
153889.345/ 0.43 to get 357882.198
1.7704068535125e28 J/357882.198 = 4.947e22 or 11.823370808930999232 teratons of TNT. Which is 6-B.