To determine the duration of the trip as measured by someone on the spaceship, we can use the time dilation formula from special relativity:
Δt' = Δt / √(1 - (v^2/c^2))
Where:
Δt' is the time dilation experienced by the traveler on the spaceship,
Δt is the time measured in the Earth's rest frame (11.2 years in this case),
v is the velocity of the spaceship (0.964c, where c is the speed of light),
and c is the speed of light.
Plugging in the values:
Δt' = 11.2 / √(1 - (0.964^2))
Δt' = 11.2 / √(1 - 0.929296)
Δt' = 11.2 / √(0.070704)
Δt' = 11.2 / 0.265932
Δt' = 42.1 years
Therefore, the trip takes approximately 42.1 years as measured by someone on the spaceship.