Could a Smoke Detector Serve as a Sail for Spacecraft Propulsion?

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SUMMARY

The discussion centers on the feasibility of using a smoke detector as a propulsion mechanism for spacecraft by leveraging alpha decay. Participants clarify that while alpha decay can produce a minute net force, it is insufficient for practical propulsion compared to established technologies like ion engines. The comparison highlights that the mass loss from a smoke detector over time would be negligible, with estimates suggesting it would remain undetectable even after a century. The Deep Space 1 probe, which utilizes a 36kg fuel supply for its ion thruster, serves as a benchmark for effective propulsion systems.

PREREQUISITES
  • Understanding of alpha decay and its mechanisms
  • Basic knowledge of spacecraft propulsion systems
  • Familiarity with Einstein's mass-energy equivalence principle (E=mc²)
  • Awareness of ion propulsion technology and its applications
NEXT STEPS
  • Research the principles of alpha decay and its applications in propulsion
  • Study the operational mechanics of ion thrusters, particularly in spacecraft like Deep Space 1
  • Explore advanced propulsion concepts, including thermoelectric generators
  • Investigate the limitations of using low-mass propulsion systems in space exploration
USEFUL FOR

Spacecraft engineers, physicists, and researchers interested in innovative propulsion technologies and the practical applications of nuclear decay in space exploration.

synch
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Looking at a humble smoke detector - a metal plate with some alpha source on one side. I guess the fission products / apha etc emitted in one direction are absorbed into the metal, and the opposite direction go into space. So there should be a minute net force ? Would that be useful as a "sail" in space ? It seems to me it would be simpler than a thermoelectric generator and ion engine (?)
 
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synch said:
Looking at a humble smoke detector - a metal plate with some alpha source on one side. I guess the fission products / apha etc emitted in one direction are absorbed into the metal, and the opposite direction go into space. So there should be a minute net force ? Would that be useful as a "sail" in space ? It seems to me it would be simpler than a thermoelectric generator and ion engine (?)
Why are you calling alpha decay "fission"?

https://en.wikipedia.org/wiki/Nuclear_fission

https://en.wikipedia.org/wiki/Alpha_decay
 
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synch said:
Looking at a humble smoke detector - a metal plate with some alpha source on one side. I guess the fission products / apha etc emitted in one direction are absorbed into the metal, and the opposite direction go into space. So there should be a minute net force ? Would that be useful as a "sail" in space ? It seems to me it would be simpler than a thermoelectric generator and ion engine (?)

Yeah a minute force would be expected, but far too small to be useful. To estimate how small it is, figure out how much mass loss the smoke detector experiences in a year, and then use ##E=mc^2## My guess is that after 100 years, the mass loss would still be far too small to measure by ordinary means.

By contrast, the Deep Space 1 probe carries 36kg of fuel for the ion thruster.
 
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