Visual distortions near a neutron star and black hole

  title={Visual distortions near a neutron star and black hole},
  author={Robert J. Nemiroff},
  journal={American Journal of Physics},
  • R. Nemiroff
  • Published 1 July 1993
  • Physics
  • American Journal of Physics
The visual distortion effects visible to an observer traveling around and descending to the surface of an extremely compact star are described. Specifically, trips to a ‘‘normal’’ neutron star, a black hole, and an ultracompact neutron star with extremely high surface gravity, are described. Concepts such as multiple imaging, red‐ and blue‐shifting, conservation of surface brightness, the photon sphere, and the existence of multiple Einstein rings are discussed in terms of what the viewer would… 
Distortion of the stellar sky by a Schwarzschild black hole
The optical appearance of the stellar sky for an observer in the vicinity of a black hole is dominated by bending of light, the frequency shift, and the magnification caused by gravitational lensing
An Illustrated History of Black Hole Imaging : Personal Recollections (1972-2002)
The Event Horizon Telescope Consortium is on the verge to provide the first telescopic image of massive black holes SgrA* and M87* surrounded by accretion disks, at a resolution scale comparable to
Analytic Kerr black hole lensing for equatorial observers in the strong deflection limit
In this paper we present an analytical treatment of gravitational lensing by Kerr black holes in the limit of very large deflection angles, restricting to observers in the equatorial plane. We
Gravitational Lensing by Black Holes: A Comprehensive Treatment and the Case of the Star S2
Light rays passing very close to a black hole may experience very strong deviations. Two geometries have been separately considered in recent literature: a source behind the black hole (standard
Retrolensing by a charged black hole
Compact objects with a light sphere such as black holes and wormholes can reflect light rays like a mirror. This gravitational lensing phenomenon is called retrolensing and it is an interesting tool
Extreme gravitational lensing in vicinity of Schwarzschild-de Sitter black holes
We have developed a realistic, fully general relativistic computer code to simulate optical projection in a strong, spherically symmetric gravitational field. The standard theoretical analysis of
Gravitational lensing by black holes
We review the theoretical aspects of gravitational lensing by black holes, and discuss the perspectives for realistic observations. We will first treat lensing by spherically symmetric black holes,
Gravitational Lensing Characteristics of the Transparent Sun
The transparent Sun is modeled as a spherically symmetric and centrally condensed gravitational lens using recent standard solar model (SSM) data. The Sun's minimum focal length is computed to a
Strong deflection gravitational lensing by a modified Hayward black hole
A modified Hayward black hole is a nonsingular black hole. It is proposed that it would form when the pressure generated by quantum gravity can stop matter’s collapse as the matter reaches the Planck
Equatorial light bending around Kerr-Newman black holes
We study the deflection angle of a light ray as it traverses on the equatorial plane of a charged spinning black hole. We provide detailed analysis of the light ray's trajectory, and derive the


The black hole as a gravitational ``lens''
We discuss the ‘‘images’’ formed when the light from a distant source suffers a large deflection in the intense gravitational field in the immediate vicinity of a Schwarzschild black hole. The light
Image of a spherical black hole with thin accretion disk.
Black hole accretion disks are currently a topic of widespread interest in astrophysics and are supposed to play an important role in a number of high-energy situations. An investigation of the
The gravitational field outside of a nonrotating black hole is described using the Schwarzschild metric. The geodesic equations of the Schwarzschild metric are derived and those describing null and
Stellar sky as seen from the vicinity of a black hole
The stellar sky—as seen from the vicinity of a black hole—is discussed as a method to visualize the effects of light deflection. For rotating black holes, spatial axes defining the spherical angles
Hot spots on neutron stars. II. The observer's sky
The gravitational lensing properties of neutron stars are explored, and the results are applied to x-ray emission from radio and x-ray binary pulsars. A simple method is described and illustrated for
'Flux conservation' by a Schwarzschild gravitational lens
It is demonstrated, by an explicit calculation, that a single, isolated Schwarzschild gravitational lens leads to a vanishing net total amplification on its own, without any help from other lenses.
Unusual radio source MG1131+0456: a possible Einstein ring
We report the discovery of extremely unusual structure in the radio source MG1131 + 0456. In a radio map with sub~arc$econd resolution the object appears as an elliptical ring of emission accompanied
White Dwarfs and Neutron Stars
A modulation contrast microscope employs a closely wound lamp filament of a rectangular configuration as an illuminating source. The image of the filament is registered on a Fourier plane to which
New models for neutron stars
A new type of neutron star model (Q stars), in which high-density, electrically neutral baryonic matter is a coherent classical solution to an effective field theory of strong forces, and is bound in
Cosmological Applications of Gravitational Lensing
The discovery by Walsh et al (1979) of the first bona fide gravitational lens, the doubly-imaged quasar, Q0957 + 561, happened at an opportune time, following several prescient theoretical papers,