Light travels along straight geodesics bending around heavy planetary masses.

Has an experiment been designed or planned where light is beamed/pulsed, goes out near to or grazing safely around far-off planets/known configuration planetary formations or black holes and comes back to same or nearby points on earth? As if through a huge fiber-optic cable?


2 Answers 2


I don't think there exists a system where this would be a feasible experiment.

a)we need a black hole (object with a photonsphere). ordinary objects like stars or clusters there of are just not dense enough.

b) we need to know where it is. there are few that we can really pinpoint

c) distance. Sgr A* is something like 25000 light years away. aka your experiment would take 50000 years to run.

d) aim at distance. The Event Horizon Telescope will be barrely able to resolve its shadow. try aiming a beam that will be strong enough that it is detectable and precise enough that with all the mess in between it is calculated so precise that it hits the right point on earth trajectory in 50000 years time.

Unless we find a black hole close by (max like 10 light years) i don't think this is a feasible experiment


No , the kind of experiment you said has not been done yet and i dont think it will be possible to do so practically. But gravitational lensing has been proved practically in solar eclipse. A light ray was deflected by the gravitational pull of our sun and a star that was right behind the sun(which could not supposed to be seen seen)was seen right at the side of the sun.


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