Introduction[]
Creating or blowing up a dimension with a starry sky is an extremely common feat in fiction, but we currently lack solid values for these feats, and just peg them at 4-A
Let's try to put a number on them, shall we?
The Calc[]
The farthest bright star visible from the unaided eye is Eta Carinae A, a red hypergiant that lies roughly 7,500 light years away from our little dot full of life.
Said star is, on average, 120 times more massive than our Sun at 2.387e32kg, with a radius of 167 million kilometers. It is mostly convective, which means we're going with the polytrope of 1.5 for the GBE.
- (3*6.67408e-11*2.387e32^2)/(167000000000(5-1.5)) = 1.9517895e43 joules
7500 light years is equal to 7.0955e+19 meters.
- 4*1.9517895e43*(7.0955e+19/167000000000)^2 = 1.4093732e61 joules, or 140.9373 PetaFoe (Multi-Solar System level)
This would be the safest bet.
Before anyone corrects me, V762 Cassiopeia is often said to be the farthest observable star, being visible to the eye at 16,300 light years away, but more recent measurements have reduced that figure to a measly 2,700-2,800ly.
As a means of reflection, just over 100 years ago we could see some stars located in the Andromeda Galaxy, well over 2.5 million light years away from Earth. This is no longer possible anywhere on Earth, with Andromeda itself barely being visible.