- #1

Karagoz

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A rocket is in constant velocity. The velocity of the rocket is 150Mm/s (or 0.5 of the speed light, or 150 million meters per second) relative to us (we as observer).

We observe two lights, one moving in parallell with the rocket, another is moving in the opposite direction.

Below I have made a picture of what we (or observers staying still relative to the rocket outside) see in one moment (above), and what we see after one second (below). It's from our perspective.

The speed of light is constant for all observers. So the astronauts in the rocket will observe something different than us.

The Lorentz factor γ will be: 1/√(1-0.5^2) = 1.1547.

Their time be slower, so their time will be 1 = 1/γ = 1/1.1547 = 0.866.

So they'll experience our 1 second as 0.866 seconds.

And that means with the velocity 150 Mm/sec, they'll experience that they have traveled

0.866*150Mm = 129.9Mm.

The light has traveled 300Mm.

So with that calculation, they're 300-129.9 = 170.1Mm behind the light.

But since they too will observe the light to have same velocity, within 0.866 seconds they should see the light traveled past them by 259.8Mm (0.866*300).

And they should see the other light not reached them after 0.866 seconds or after one second.

How would the astronauts in the rocket observe what happened from that moment to one second after that moment illustrated in the pictured above?

We observe two lights, one moving in parallell with the rocket, another is moving in the opposite direction.

Below I have made a picture of what we (or observers staying still relative to the rocket outside) see in one moment (above), and what we see after one second (below). It's from our perspective.

The speed of light is constant for all observers. So the astronauts in the rocket will observe something different than us.

The Lorentz factor γ will be: 1/√(1-0.5^2) = 1.1547.

Their time be slower, so their time will be 1 = 1/γ = 1/1.1547 = 0.866.

So they'll experience our 1 second as 0.866 seconds.

And that means with the velocity 150 Mm/sec, they'll experience that they have traveled

0.866*150Mm = 129.9Mm.

The light has traveled 300Mm.

So with that calculation, they're 300-129.9 = 170.1Mm behind the light.

But since they too will observe the light to have same velocity, within 0.866 seconds they should see the light traveled past them by 259.8Mm (0.866*300).

And they should see the other light not reached them after 0.866 seconds or after one second.

How would the astronauts in the rocket observe what happened from that moment to one second after that moment illustrated in the pictured above?

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