How to destroy the worldJacob Schwartz,
Society of Physics Students, Week 10, Fall 2011
Acknowledgements
http://qntm.org/destroy
Scope/Goals
To make The Earth no longer be a planet
DefinitionsIAU definition:
Planet: a celestial body that
1. is in orbit around the Sun
2. has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape,
3. has cleared the neighborhood around its orbit
Ways not to destroy earth
Hurling it into interstellar space,
Moving it into orbit around a gas giant
Moving it into a solar orbit whose neighborhood is not cleared
These don’t count!
Information on Earth
Radius: 6371 km
Mass: 5.9722 x 10^24 kg
= 5972200000000000000000000 kg ball of rock and ironSemi-major axis of orbit: 149,598,261 km
Average orbital speed: 29.78 km/s
CalculationsRotational Angular Momentum:
Assuming constant density, spherical earth
L = I w = 2/5 M R2 w = 7.05 x 1033
T_rotation = ½ I w^2 = 2.56 x 1029
Energy output of sun over 11 minutes
CalculationsOrbital angular momentum:
L = m r v = 2.66 x 1040 J s
Orbital Kinetic Energy:
T= ½ m v2 = 2.658 x 1033 J
For comparison: Mean solar output = 3.846×1026 W
80 days of sun’s entire output
Method 1: Annihilated by
Antimatter EarthYou will need: An entire planet Earth made from antimatter
E= (2m) c2 = 1.07 x 1042 Joules
89 million years of sun output
Method 1: Annihilated by
Antimatter EarthFeasability: 2/10
Earth’s final resting place: gamma rays
Method 2: Fissioned
You will need: a universal fission machine (e.g. a particle accelerator), an unimaginable amount of energy
Method: Take every single atom on planet Earth and individually split each one down to become hydrogen and helium.
Method 2: Fissioned
Solar wind carries H, He away
Planet essentially evaporates
Method 2: Fissioned
Feasability: 2/10
Earth’s final resting place: gas cloud
Method 3: Sucked into a microscopic
black holeYou will need: a microscopic black hole, mass > Mount Everest or so
Method: Drop black hole
into earth, wait
Method 3: Sucked into a microscopic
black holeFeasability: 3/10
Earth’s final resting place: A black hole orbiting the sun
Method 4: Cooked in a solar oven
Surface area of Earth: 5.112 * 1014 m2
Black-body temperature of Earth: ~287 K
Power radiated by Earth: ~1.966 * 1017 kg m2 s-3
Black-body temperature of Earth after being completely boiled: ~3134K
Power radiated by Earth at this temperature: ~2.796 * 1021 kg m2 s-3
Ratio of these two powers: 1 to ~14,000
Method 4: Cooked in a solar oven
Need to have 14000 * Earth’s surface area worth of mirrors : 1.80 * 1018 m2
Method 4: Cooked in a solar oven
Method 4: Cooked in a solar oven
Feasability: 3/10
Earth’s final resting place: gas cloud
Method 5: Overspun
Increase rotation speed until Earth flies apart : centrifugal force > gravity
r w2 > 9.8 m/s2
w > 0.00124 or Period of rotation < 84 minutes
Increase rotational kinetic energy by 7.4*1031 J
2 days of solar output
Method 5: Overspun
Method 5: Overspun
Feasability: 4/10
Earth’s final resting place: A new asteroid belt
Method 6: Destroyed by
Antimatter BombGravitational Binding Energy of Earth:
U = 3/5 G M2 / R = 2.24 * 1032
Need enough antimatter to overcome this
m c^2 = U
Only need half of that!
m = 1.25 * 1015 kg of antimatter! ~ 200 Mt Everest
Sun’s energy output over one week
Method 6: Destroyed by an Antimatter BombFeasability: 4/10
Earth’s final resting place: a new asteroid belt around the sun
Method 7: Sucked into a giant black
holeYou will need: a black hole, extremely powerful rocket engines.
Nearest black hole: ~1600 light years from earth
Method 7: Sucked into a giant black
holeFeasibility rating: 6/10.
Earth’s final resting place: Part of the black hole
Method 8: Deconstructed
You will need: a mass driver
Method: Dig up a chunk of earth, launch it at escape velocity or more
A million tonnes per second 189,000,000 years.
Note that Earth’s mass increases at ~~~ 1000 tons/day
Method 8: Deconstructed
Feasibility: 6/10
Earth’s final resting place: Scattered throughout the solar system
Method 9: Pulverized
You will need: Something large and heavy
Method: Smash it into earth
Example:
5,000,000,000,000-tonne asteroid at 90% of light speed
Note that a Mars-sized object once hit Earth … this led to the moon.
Method 9: Pulverized
Feasibility: 7/10
Earth's final resting place: a variety of roughly Moon-sized chunks of rock
Method 10: Hurled into the
SunYou will need: Earthmoving Equipment
Solar sails, giant rockets, large asteroid, gravity assist
Method 10: Hurled into the
SunFeasibility: 9/10
Earth's final resting place: a small globule of vaporized iron sinking slowly into the heart of the Sun.
Method 11: Tidal Forces
Move Earth close to the Sun / Jupiter
Tidal forces rip it apart.
Method 11: Tidal Forces
Feasibility: 9/10
Earth's final resting place: lumps of heavy elements, torn apart, sinking into the massive cloud layers of Jupiter, never to be seen again.
Thanks!
