Asteroid Mining for Resources and Energy
This essay examines the mining of asteroids as a potential source of resources and energy for Earth.
It examines the number, locations, threat, separation, mass, best targets, potential resources, flight capability, distances, types of missions, investment and financial returns.
Conclusions are then drawn from the data.
Number
There are estimated to be 1,500,000 asteroids
Source: https://solarsystem.nasa.gov/planets/profile.cfm?Object=Asteroids&Display=OverviewLong
There are estimated to be 10,003 near-Earth asteroids.
Source: https://solarsystem.nasa.gov/planets/profile.cfm?Object=Asteroids&Display=OverviewLong
The number of near earth asteroids over 1 km in diameter is thought to be 861.
Source: https://solarsystem.nasa.gov/planets/profile.cfm?Object=Asteroids&Display=OverviewLong
The asteroid belt is estimated to contain 1.1 and 1.9 million asteroids larger than 1 km (0.6 mile) in diameter, and millions of smaller ones.
Source: https://solarsystem.nasa.gov/planets/profile.cfm?Object=Asteroids&Display=OverviewLong
Threat
1,409 near earth asteroids are classified as potentially hazardous asteroids - those that could pose a threat to Earth.
Source: https://solarsystem.nasa.gov/planets/profile.cfm?Object=Asteroids&Display=OverviewLong
Separation
The asteroids are separated on average by 1,000,000 to 3,000,000 km
Source: https://solarsystem.nasa.gov/planets/profile.cfm?Object=Asteroids&Display=OverviewLong
Total Mass
The total mass of all the asteroids is less than half that of Earth's Moon.
Source: https://solarsystem.nasa.gov/planets/profile.cfm?Object=Asteroids&Display=OverviewLong
Moon Mass = 7.34767309 × 1022 kg
50 % x 7.34767309 × 1022 kg
= 3.6738365 x 1022 kg
Source: https://www.google.co.uk/?gws_rd=ssl#safe=strict&q=moon+mass
Half the mass of the asteroid belt is contained in the four largest asteroids Ceres, Vesta, Pallas and Hygiea.
50 % x 3.6738365 x 1022 kg
= 1.83691825 × 1022 kg
Ceres has a diameter of 950 km, and Vesta, Pallas, and Hygiea. have mean diameters greater than 400 km.
The remaining bodies in the asteroid belt range down to the size of a dust particle.
Source: http://en.wikipedia.org/wiki/Asteroid_belt and associated refs.
Mass of Ceres = 9.47 × 1020 kg
Density of Ceres = 2.077 g/cm3
Moon density as a comparison = 3.34 g/cm³
Source: https://www.google.co.uk/?gws_rd=ssl#safe=strict&q=moon+density
Source: http://en.wikipedia.org/wiki/Ceres_(dwarf_planet)
Mass of Vesta = 258.9 x 1018 kg
Density of Vesta = 3.42 g/cm³
Moon density as a comparison = 3.34 g/cm³
Source: https://www.google.co.uk/?gws_rd=ssl#safe=strict&q=moon+density
Source: http://en.wikipedia.org/wiki/4_Vesta
Mass of Pallas = 210.8 x 1018 kg
Density of Pallas = 2.8 g/cm³
Moon density as a comparison = 3.34 g/cm³
Source: https://www.google.co.uk/?gws_rd=ssl#safe=strict&q=moon+density
Source: http://en.wikipedia.org/wiki/2_Pallas
Mass of Hygiea = 8.67 × 1019 kg
Density of Hygiea = 2.08 g/cm³
Moon density as a comparison = 3.34 g/cm³
Source: https://www.google.co.uk/?gws_rd=ssl#safe=strict&q=moon+density
Source: http://en.wikipedia.org/wiki/10_Hygiea
The Potential Resources
75% of the asteroids are C-type or carbonaceous asteroids.
They are located in the outer reaches of the asteroid belt between 0.27 au to 3.2 au from the sun.
They may contain hydrated water minerals.
They do not contain Hydrogen, Helium and volatiles.
Source: http://en.wikipedia.org/wiki/C-type_asteroid
Source: http://en.wikipedia.org/wiki/Asteroid_belt
17% of the asteroids are S-type or asteroids containing silicate and some metals.
They are contained within the asteroid belt. 2.2 to 3.2 au from the Sun
Source: http://en.wikipedia.org/wiki/Asteroid_belt
10% of the asteroid belt are M-type or metallic asteroids containing nickel and iron
They are contained within the asteroid belt. 2.2 to 3.2 au from the Sun
Source: http://en.wikipedia.org/wiki/Asteroid_belt
The Current Flight Capability
The current capability in space travel in terms of speed of flight is 13.3 AU / yr.
The Distance Problem
The distance to the asteroid belt from the sun is 2.2 to 3.2 Earth Sun distance (Au).
Source: space-facts.com/asteroid-belt/
The time to the furthest extent of the asteroid belt.
= 3.2 Au = 4 months out and 4 months back = 1 year x 2 incl. mining = 2 years
The time to get to Ceres
= 2.9 Au = 3 months out and 3 months back = 6 months x 2 incl. mining = 1 year
The time to Vesta
= 2.57 Au = 3 months out and 3 months back = 6 months x 2 incl. mining = 1 year
The time to Pallas
= 3.41 Au = 4 months out and 4 months back = 1 year. x 2 incl. mining = 2 years
The time to Hygiea
= 3.7 Au = 4 months out and 4 months back = 1 year. x 2 incl. mining = 2years
Manned Mission Investment
The Apollo Moon mission took 8 days and $8,720,000,000 in 2014 money.
= $8,720,000,000 / 8 days
= 1.09 billion US$ per day
Source: Apollo Program Budget Appropriations NASA.
To send a crew to an asteroid would take.750 days
= 1.09 billion US$ x 750 days
= approx.$820,000,000,000 per mission
The total USA budget expenditure requested in 2015
= $3.90 trillion
= Each asteroid mission would therefore cost the equivalent of 21% of the total US budget expenditure for 2015.
Non- Manned Mission Investment
The requirements for a non-manned mission would be similar to the recent Rosetta mission to an asteroid to collect survey information and samples.
The Rosetta mission time was 10 years and cost $1,800,000,000.
= $1,800,000,000 / 10 years
Source: http://en.wikipedia.org/wiki/Rosetta_(spacecraft)
= $493,150 per day including the survey, landing, and data retrieval
Sample Return Stage
Based on the successful 1970 Luna 16 Soviet Union return sample mission approx. 101 grams can be surveyed, excavated and returned to Earth.
Source: http://en.wikipedia.org/wiki/Sample_return_mission
To send an un-manned mission to an asteroid would take. 1 to 2 years.
= $360,000,000 per outbound mission.
= approx $4.5 billion/ 24 soviet luna missions
= luna 16 sample return cost approx.$187,500,000 in 2014 money.
Source: http://en.wikipedia.org/wiki/Luna_programme
= Total cost for an un-manned asteroid, outbound, mining and sample return mission approx. $550,000,000 total mission cost
The total USA budget expenditure requested in 2015
= $3.90 trillion
= Each unmanned asteroid mission would therefore cost the equivalent of 0.014% of the total US budget expenditure for 2015.
Investment and Return
Assuming the unmanned type of mission and using one of the 4 best asteroids; Ceres; as a cost check on the return on investment.
= Ceres Mission $550,000,000 per mission
= Return sample potential size as Luna 16 = 101 grams = 3.5 oz
= Density of Ceres = 2.077 g/cm3
= 48 cm3 of material returned to Earth
= Ceres has a density less than the moon so the likely material return values would be minimal. However assuming that rare materials could be obtained to make the mission viable.
= Platinum at $1154 per oz = $4039 value of sample = 136172 missions to pay for 1 mission.
Source: http://www.platinum.matthey.com/prices/price-charts
= Helium 3 at $15,000 per gram = $1,515,000 value of sample = 363 missions to pay for 1 mission.
Source: USA DOE
Conclusions
The number of asteroids indicates that multiple outbound and sample return missions will be needed.
The data indicates that there will be varying fuel loads and varying transit and return times.
Therefore profit potential will vary per mission.
The Threat data indicates that the target asteroids will need to be carefully chosen so that they do not endanger the Earth by being mined, altering mass, orbit and so impacting onto the Earth.
The Separation data indicates that additional resources will have to be expended to get to and return resources from each individual asteroid.
The Mass data could indicate that the total number of asteroids or the 4 best asteroids do not have a high abundances of heavy metals.
The data also indicates that water resources are possibly located in the outer parts of the asteroid belt.
Maximum resources would have to be expended to reach these locations, mine them and return them to Earth or use these resources as fuel manufacturing locations for ongoing missions.
Only a small proportion to the asteroid belt could be mined for silicates and trace metals.
The data indicates that the mission time would be approx.1 to 2 years
The return on any investment will then be in the region of 1 to 2 years.
There are two choices of mission type. Manned and Un-manned.
The data indicates that un-manned missions are currently technologically possible and also more cost effective.
From the above data missions to the asteroid belt using unmanned missions are feasible but not effective in terms of cost, return of investment or sample size returned.
Ian K Whittaker
Websites:
https://sites.google.com/site/architecturearticles
Email: iankwhittaker@gmail.com
11/05/2015
14/10/2020
1331 words over 4 pages