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Assuming E = F*d, 0.136*1*4.13e+16 = 5.37e15 Joules will be required for each kilogram carried to Alpha Centauri in 35 years.   
 
Assuming E = F*d, 0.136*1*4.13e+16 = 5.37e15 Joules will be required for each kilogram carried to Alpha Centauri in 35 years.   
  
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This would require an unimaginable amount of mass for a conventional chemical rocket, and is a completely impractical power requirement for any sort of passive solar sail concept.
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This would require an unimaginable amount of mass for a conventional chemical rocket, is a completely impractical power requirement for any sort of passive solar sail concept.
 
   
 
   
 
Further, the top speed is fast enough to require a recalculation using relativistic physics to model the problem.  This means that the energy budget will need to increase, as the relativistic mass of the probe will increase, requiring more force (and thus more energy) to accelerate and decelerate near its top speed than this calculation returns.
 
Further, the top speed is fast enough to require a recalculation using relativistic physics to model the problem.  This means that the energy budget will need to increase, as the relativistic mass of the probe will increase, requiring more force (and thus more energy) to accelerate and decelerate near its top speed than this calculation returns.
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[https://en.wikipedia.org/wiki/Breakthrough_Starshot Active], laser based propulsion methods require currently non-existent and purely speculative laser and materials technologies, as well as a power plant equivalent to 12,500 of the [https://www.power-technology.com/features/feature-largest-nuclear-power-plants-world/ World's Largest Nuclear Plant] to transport sub-gram masses on this timescale.  This also assumes that any probes can be steered accurately enough across interstellar distances to come close enough to image with any resolution the bodies they will be passing at a non-trivial fraction of c.  
 
[https://en.wikipedia.org/wiki/Breakthrough_Starshot Active], laser based propulsion methods require currently non-existent and purely speculative laser and materials technologies, as well as a power plant equivalent to 12,500 of the [https://www.power-technology.com/features/feature-largest-nuclear-power-plants-world/ World's Largest Nuclear Plant] to transport sub-gram masses on this timescale.  This also assumes that any probes can be steered accurately enough across interstellar distances to come close enough to image with any resolution the bodies they will be passing at a non-trivial fraction of c.  
  
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Short of FTL travel or near-perfect mass-energy conversion technology, transporting more than a fraction of a gram of material to Alpha Centauri in a human lifetime will be unachievable.  Short of an enormous breakthrough in power generation, transporting even a fraction of a gram is impossible.
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Short of FTL travel or near-perfect mass-energy conversion technology, transporting more than fraction of a gram of material to Alpha Centauri in a human lifetime will be unachievable.  Short of an enormous breakthrough in power generation, transporting even a fraction of a gram is impossible.
  
 
Nonetheless, [http://breakthroughinitiatives.org/challenges/3 Breakthrough Starshot] is attempting to send many gram-sized probes to Alpha Centauri within the century.  Following current technological trends, they expect the efficiency of laser-based propulsion to increase by launch time, allowing launches driven by an unreasonably-large-but-achievable amount of power.  The top speed needed is halved by refraining from slowing at all at the destination: the probes will aim a distance away from the target, so that it traverses by slowly enough for a camera to rotate and track it, even at near-light speeds.  To account for error and space dust, the plan is to launch many tiny probes simultaneously.  They may only be able to accomplish their goal if they can get enough funding to actually affect the global economy enough to make the technologies they require more efficient to produce.  Launches would additionally burn incredible quantities of natural gas.
 
Nonetheless, [http://breakthroughinitiatives.org/challenges/3 Breakthrough Starshot] is attempting to send many gram-sized probes to Alpha Centauri within the century.  Following current technological trends, they expect the efficiency of laser-based propulsion to increase by launch time, allowing launches driven by an unreasonably-large-but-achievable amount of power.  The top speed needed is halved by refraining from slowing at all at the destination: the probes will aim a distance away from the target, so that it traverses by slowly enough for a camera to rotate and track it, even at near-light speeds.  To account for error and space dust, the plan is to launch many tiny probes simultaneously.  They may only be able to accomplish their goal if they can get enough funding to actually affect the global economy enough to make the technologies they require more efficient to produce.  Launches would additionally burn incredible quantities of natural gas.

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