Caption: "Gravitational lensing
by a black hole:
An animation of a
computer simulation
of gravitational lensing caused by
a
Schwarzschild black hole
going past a background galaxy.
The observer is moving with the
black hole;
the background galaxy is
at rest
relative to its own center of mass
inertial frame.
A secondary Einstein ring image of the galaxy can be seen within the black hole primary Einstein ring image on the opposite direction of that of the galaxy. The secondary Einstein ring image grows/shrinks (remaining within the primary Einstein ring image) as the primary Einstein ring image approaches/recedes from the black hole. The surface brightness of the two images remain constant, but their angular sizes vary, hence producing an amplification of the galaxy luminosity as seen by a distant observer. The maximum amplification occurs when the background galaxy (or in the present case a bright part of it) is exactly behind the black hole." (Slightly edited.)
Note the black circle region is NOT the event horizon. It is the black hole shadow. For an explication of black hole shadow, see Black hole file: black_hole_shadow.html.
See Black hole keywords below (local link / general link: black_hole_keywords.html):
EOF
Credit/Permission: ©
User:Urbane Legend,
Alain Riazuelo AKA User:Alain r
before or circa 2007
(uploaded to Wikipedia
by User:Siebrand,
2007) /
Creative Commons
CC BY-SA 3.0.
Image link: Wikipedia:
File:Black hole lensing web.gif.
Local file: local link: black_hole_gravitational_lensing.html.
File: Black hole file:
black_hole_gravitational_lensing.html.