Trip to Saturn: Constant Acceleration of 9.81 m/s^2 - Is It Possible?

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Discussion Overview

The discussion revolves around the feasibility of a spaceship achieving a constant acceleration of 9.81 m/s² to reach Saturn. Participants explore the implications of such acceleration on travel time, the effects of relativity, and the experience of gravity within the spaceship.

Discussion Character

  • Exploratory
  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant questions whether a constant acceleration of 9.81 m/s² would allow them to stand in the spaceship as if under Earth's gravity, while also calculating the time to reach Saturn based on this acceleration.
  • Another participant provides an alternative calculation for the time to reach Saturn, suggesting it could be as short as 8.5 days if accounting for deceleration.
  • A different participant acknowledges an error in their initial calculations regarding travel time, adjusting their findings to suggest a "free fall" scenario could take 6 days, resulting in a much lower final velocity of 1.70% of light speed.
  • One participant highlights the hypothetical nature of achieving such acceleration, noting that if it were possible, one could traverse the universe within a lifetime.
  • Another participant discusses the implications of relativity, stating that as the spaceship's velocity increases, its mass would also increase, complicating the energy requirements for sustained acceleration.

Areas of Agreement / Disagreement

Participants express differing views on the calculations and implications of constant acceleration, with no consensus reached on the feasibility of the proposed travel times or the effects of relativity on mass and energy requirements.

Contextual Notes

Some calculations depend on assumptions about constant acceleration and neglect factors such as fuel source limitations and the effects of relativistic mass increase, which remain unresolved in the discussion.

Mootlime
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If I am in a spaceship and it begins a constant acceleration of 9.81 m/s^2, would I be able to stand up in the spaceship and it would feel the same as gravity? (This is assuming the fact that my feet were placed in the direction of the thrust source.)

I've done some equations, and a ship with this hypothetical acceleration capacity (regardless of fuel source, and assuming it could compensate for its mass increase due to relativity)...

My calculations put it at reaching Saturn in 225 days...

Here is the data I am using:

Distance to Saturn = 1,321,416,800 km

After 24 hours of continued acceleration (+9.81 m/s every second) the velocity would be roughly 848,000 m/s

By day 100 it would be 84,800,000 m/s

And by the day you reached Saturn (day 225) it would be 190,800,000 m/s or roughly 426 million miles per hour -- and 63.64% of the speed of light.

Are these numbers totally wrong? Someone smarter please help me. Thanks!
 
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The velocity after time t, is gt, but the distance you've reached after a time t = (1/2)gt^2 and this should be equal to the distance to saturn.

this gets you t ^2 = 2(1.321 * 10^12)/9.81, so t = 5.19 * 10^5 s = 144 hours = 6.01 days.
If you want to decelerate as well, you'd accelerate for half the distance, which you reach in 4.25 days, and then decelerate for the same time, reaching saturn after 8.5 days.
 
I adjusted my equations and found the error (was multiplying by 60 instead of 86,400 -- that certainly does change the results.) To "free fall" to Saturn with the assumption of Earth's gravity (and no friction) would take 6 days :) I find that kind of interesting. So at the end of the "fall" you'd only be going 1.70% light speed. That makes a ton more sense than what crazy results I had. Thank you.
 
IF you could accelerate at 9.81m/s2, you could cross the width of the universe well within your lifetime. It's interesting, but it's a BIG "if".
 
Mootlime said:
If I am in a spaceship and it begins a constant acceleration of 9.81 m/s^2, would I be able to stand up in the spaceship and it would feel the same as gravity? (This is assuming the fact that my feet were placed in the direction of the thrust source.)

I've done some equations, and a ship with this hypothetical acceleration capacity (regardless of fuel source, and assuming it could compensate for its mass increase due to relativity)...
Since the person standing in the spaceship is motionless with respect to the spaceship, there would be no "mass increased due to relativity".
 
I was speaking of the fuel source/acceleration problem, that as the ship increased in velocity it would also increase in mass because of relativity, meaning it would need more energy to sustain its acceleration. I was told that this is one of the main problems with accelerating up to 99% of the speed of light.
 

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