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Author Topic: What would be the transit time to Mars with unlimited power?  (Read 1044 times)

Offline Semaphore

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It's going to be very difficult to protect astronauts from radiation during a trip to Mars, so what is the shortest transit time based on a very powerful drive, say a fusion drive? That would assume accelerating and decelerating at, say, 2g, or whatever load people could deal with on a constant basis. I suppose relativistic effects would kick in.


 

Online alancalverd

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s = 0.5 a t^2 where s = distance, a = acceleration and t = time (you did that at school, surely?)

Minimum transit distance is probably 10^11 meters. Put a = 20 m/s^2 (a bit more than 2g) then t^2 = 10^10 so t = 10^5 seconds, just over a day.
 

Offline Semaphore

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s = 0.5 a t^2 where s = distance, a = acceleration and t = time (you did that at school, surely?)

Minimum transit distance is probably 10^11 meters. Put a = 20 m/s^2 (a bit more than 2g) then t^2 = 10^10 so t = 10^5 seconds, just over a day.

You don't need to be sarcastic.
 
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Offline chiralSPO

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s = 0.5 a t^2 where s = distance, a = acceleration and t = time (you did that at school, surely?)

Minimum transit distance is probably 10^11 meters. Put a = 20 m/s^2 (a bit more than 2g) then t^2 = 10^10 so t = 10^5 seconds, just over a day.

I assume that the OP intended on landing on Mars, not whizzing by it, or creating a new impact crater on its surface...

If one wanted to accelerate at 20m/s2 until the half-way point, and then decelerate at the same rate until the destination is reached, then just double the time it takes to get to 5x1010 meters.
 
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Online alancalverd

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You don't need to be sarcastic.

True, but it's one of life's rare pleasures for an old man!
 

Offline Semaphore

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s = 0.5 a t^2 where s = distance, a = acceleration and t = time (you did that at school, surely?)

Minimum transit distance is probably 10^11 meters. Put a = 20 m/s^2 (a bit more than 2g) then t^2 = 10^10 so t = 10^5 seconds, just over a day.

I assume that the OP intended on landing on Mars, not whizzing by it, or creating a new impact crater on its surface...

If one wanted to accelerate at 20m/s2 until the half-way point, and then decelerate at the same rate until the destination is reached, then just double the time it takes to get to 5x1010 meters.

Thanks for correcting this guy's post.
 

Offline Semaphore

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You don't need to be sarcastic.

True, but it's one of life's rare pleasures for an old man!

That doesn't excuse it. I suppose you could have learned manners at school.
 

Offline jeffreyH

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You don't need to be sarcastic.

True, but it's one of life's rare pleasures for an old man!

That doesn't excuse it. I suppose you could have learned manners at school.

Alan will supply an answer to a science question without resort to wikipedia and it will be right. So giving him a little indulgence is well worth it.
 

Online alancalverd

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I suppose you could have learned manners at school.

Physics and chemistry makyth Man. And I'll give you full marks for a good question.
 
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Offline Semaphore

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So it takes 70711 seconds or 19.6 hours to get to the midway point and a similar time to decelerate, for a total of 1 day and 15 hours.
 

Offline chiralSPO

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So it takes 70711 seconds or 19.6 hours to get to the midway point and a similar time to decelerate, for a total of 1 day and 15 hours.

That sounds about right.
 

Online alancalverd

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As they say at NASA, rocket science is ridiculously easy. Rocket engineering is the problem.
 

Offline Semaphore

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I suppose no one has thought about why I asked the question in the first place? Apart from my lack of education.
 

Offline chiralSPO

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Perhaps it is related to Elon Musk's recent announcement that SpaceX is planning on sending people to Mars?
 

Offline Semaphore

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Perhaps it is related to Elon Musk's recent announcement that SpaceX is planning on sending people to Mars?
And?
 

Offline chiralSPO

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...and you have a fusion powered super-rocket that you're wondering what to do with?
 

Offline Semaphore

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I think we should make sure we have the right equipment before we start this adventure, otherwise people will die, either from accidents or cancer. There are plenty of things that need fixing here before we start wrecking another planet. You don't need me to identify them.
 

Offline Bill S

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Quote from: Semaphore
You don't need me to identify them.


You could flag up a few for us!

Making silly comments is another "of life's rare pleasures for an old man!".

 

Offline Semaphore

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Quote from: Semaphore
You don't need me to identify them.


You could flag up a few for us!

Making silly comments is another "of life's rare pleasures for an old man!".

That's a pretty silly comment, tbf. Do you have anything to say about the issue?
 

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