Re: starship-design: Help with formula

[Zenon Kulpa <zkulpa@zmit1.ippt.gov.pl>]

> From: Steve VanDevender <stevev@efn.org>
> 
> Zenon Kulpa writes:
>  > Please, I have lost it somewhere, no time to search or derive,
>  > what is the formula for Earth time & crew time
>  > in the (one-way) flight with constant acceleration = 1g 
>  > (half way +, half way - ) depending on the distance (in ly)?
>  > 
>  > Thanks, 
>  > 
>  > -- Zenon
> 
Thank you, but:

> For one-way acceleration:
> 
Does that mean half-way acceleration, and then half-way deceleration 
to stop at target (at distance d)?

> t = (c / a) * acosh(1 + (a * d / c^2))
> 
> t = elapsed time
>
Earth time or crew (ship) time?

> c = speed of light
> a = acceleration
> d = distance traveled
> acosh = inverse hyberbolic cosine function
> 

-- Zenon