When the light from a distant star is bent according to the gravitational lens effect, observers see the star as though it were in a different position than it really is.

Just like a convex lens made of glass, this gigantic lens in space also forms images by enlarging stars and increasing brightness. Research on wobble in space and small stars that are dim and distant is underway at a fever pitch using this effect.

Incidentally, when light from distant stars reaches the earth after skimming around the edge of the sun, gravitational refraction produces a lens-like effect that bends the light by an angle of 1.75 seconds (1 second is 1/3,600 degrees).