Stars and the Galaxies

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if alpha centauri were to all of a sudden disappear, we wouldn't knknow 4 another 4.3 years. How come? Why would this be the case?

would this be the case because its really far away from us and it's 4.3 light years away. So if it suddenly just vanished out of sight, then it would definetly take 4.3 light years to get back, because that's how long it would take its light to travel.

• Stars and the Galaxies -

The 4.3 light year distance of Alpha Centauri means that the light we are seeing now was emitted 4.3 years ago. If the star ceased to exist NOW (which is not at all likely to happen), we would not know about it for 4.3 years, because light emitted before is still on the way here.

• Stars and the Galaxies -

thanks drwls, :-)

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