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User:GiverOfThePeace/Standard Calculation for Meteors, Comets, etcetera

From The Codex

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. Though this is for only the comets KE, what would you get destroying it, taking it's surface area into account?

We already got the radius above being 5 km

Plugging it into this calculator, we get 314.159 km^2 or 3.14159e+12 cm^2.

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. Though this is for only the asteroids KE, what would you get destroying it, taking it's surface area into account?

Diameter of Itokawa is 0.5 x 0.3 x 0.2 km or 0.03 km^3, getting the cubed root gives us 0.3107232505953859 km diamter and a 0.15536162529769295 km radius

Plugging it into this calculator, we get 0.303317 km^2 or 3033170000 cm^2.

1.7704068535125e28 J/3033170000 cm^2 = 5.836820400810043618e18 J/cm^2 or Island level.