What is the maximum possible specific impulse.

AI Thread Summary
A hypothetical antimatter rocket could achieve a specific impulse (ISP) of around 1,000,000 seconds, but this is not perfectly efficient due to energy losses from mesons and gamma rays. The discussion raises questions about maximizing ISP by reducing these energy losses and whether there are theories to harness this lost energy. Currently, there are few practical theories or plans for antimatter rockets, primarily due to the extremely limited production of antimatter. The complexities of calculating potential ISP improvements remain largely unexplored. Overall, the feasibility of enhancing ISP beyond the theoretical maximum is uncertain and requires further investigation.
Ryan_m_b
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Hi there,

I'm aware that a hypothetical antimatter rocket could have a specific impulse of ~1,000,000 seconds. At first I thought that this would be the highest isp possible as antimatter/matter collision releases all the energy in the mass. However as wikipedia put's it

"It is not perfectly efficient; energy is lost as the rest mass of the charged and uncharged mesons, lost as the kinetic energy of the uncharged mesons (which can't be deflected for thrust), and lost as gamma rays."

So whilst it may be impractical to the point of impossibility what is the maximum isp that could be obtained if less energy was lost (and are their any theories on how to utilize this lost energy) Are there any theoretical ways of boosting that 1megasecond number?

Many thanks!
 
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There are currently very few theories or plans to utilize an antimatter rocket, as the production of antimatter is extremely small. You can try to crunch the numbers if you'd like, but otherwise I don't think anyone really knows unless they did the same.
 
Drakkith said:
There are currently very few theories or plans to utilize an antimatter rocket, as the production of antimatter is extremely small. You can try to crunch the numbers if you'd like, but otherwise I don't think anyone really knows unless they did the same.

I wouldn't even know where to begin I'm afraid. Thanks anyway though:smile:
 
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