Seeing all the star
Stories from Physics
for 11-14
14-16
Given a compact enough neutron star, the effects of gravitational lensing mean that the entire surface of the object can be visible to an observer at one time. Science writer Stan Gibilisco has described what an observer might see if they were unfortunate enough to be on the surface of a neutron star as it continued to collapse:
At first, everything would appear to be quite normal… But as the intensity of the gravitational field became greater and greater, and the geometric distortion of space increased, the sky would change. New stars, previously invisible because they were below the horizon, would appear to rise upward from the horizon at all points of the compass. All the stars in the sky would seem to be moving upward toward the zenith… Finally the horizon would heave upward, and you would get the feeling of being at the bottom of a huge bowl… The whole horizon would retreat to the zenith, and close off your view of the outside heavens completely.
References
Seeing all the star
R. J. Nemiroff, Visual Distortions Near a Black Hole and Neutron Star. American Journal of Physics, vol. 61, 1993, pp. 619-631.
S. Gibilisco, Understanding Einstein’s Theories of Relativity: Man’s New Perspective on the Cosmos, New York, NY, Dover Publications, Inc., pp. 158-159