July 22, 2003 - An exceptional cosmic mirage: this is the definition used by astronomers at ESO, European Southern Observatory, commenting on the shooting of the Ring of Einstein discovered in the constellation Crater, using the 3.6-m telescope at La Silla (Chile).
The light from a distant quasar was in fact distorted and amplified by a galaxy interposed the line of sight, resulting in at least four images of "ghost" of the quasar itself, and a clear bright arc. The lens galaxy is visible as a bright central spot and diffused.
The effect, predicted by theory of general relativity (1916), is known as "Einstein ring", in honor of the great German physicist. The lens is designed
with the initials RXS J1131-1231: a galaxy far, about 3.5 billion light years from Earth, whose spectrum shows a red shift (redshift) of 0.3. Much farther away, according to the interpretation of cosmological redshift, the quasar would be: 6.3 billion years, corresponding to redshift 0.66.
Einstein ring is closer to Earth so far discovered.
The light from a distant quasar was in fact distorted and amplified by a galaxy interposed the line of sight, resulting in at least four images of "ghost" of the quasar itself, and a clear bright arc. The lens galaxy is visible as a bright central spot and diffused.
The effect, predicted by theory of general relativity (1916), is known as "Einstein ring", in honor of the great German physicist. The lens is designed
with the initials RXS J1131-1231: a galaxy far, about 3.5 billion light years from Earth, whose spectrum shows a red shift (redshift) of 0.3. Much farther away, according to the interpretation of cosmological redshift, the quasar would be: 6.3 billion years, corresponding to redshift 0.66.
Einstein ring is closer to Earth so far discovered.
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