Different Simultaneity for telescopes in space and earth?

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ofirg
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I was just wondering. According to Lorentz transformations, if two events are simultaneous in one reference frame, they will generally not be simultaneous in another.
The time difference that I get between the two events in the other reference frame is

[itex]\Delta t^{`} = \gamma\beta\Delta x \approx {\Large \frac{\beta^{3}}{2}} \Delta x[/itex]

Where the approximation assumes [itex]\beta \ll 1[/itex]

Now, for space born objects [itex]\beta \approx 3 \cdot 10^{-5}[/itex] so

[itex]\Delta t^{`} \approx 10^{-14} \Delta x[/itex] where [itex]\Delta x[/itex] is in light time.

If one takes a distance of 100 Mpc then [itex]\Delta t^{`} \approx 10 sec[/itex]

So If I have two distant transient sources that give a signal at more or less the same time on earth, a space telescope will observe them at a noticeable time difference?
 
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Thanks For the reply.

I see now that I mixed up the times that the telescopes will assign to the events themselves ( the time that the sources output the signal) which will be different And the time of observation, which will be the same.