Molecular gas (notably CO) detected in the host galaxy associated with the quasar is the oldest molecular material known and provides evidence of large-scale star formation in the early universe. Thanks to the strong magnification provided by the foreground
lens, the Cloverleaf is the brightest known source of CO emission at high redshift This suggests the quasar is currently undergoing an intense wave of
star formations thus increasing its
luminosity. The 4 quasar images were originally discovered in 1984; in 1988, they were determined to be a single quasar split into four images, instead of 4 separate quasars. The
X-rays from iron atoms were also enhanced relative to X-rays at lower energies. Since the amount of brightening due to gravitational lensing doesn't vary with the wavelength, this means that an additional object has magnified the X-rays. The increased
magnification of the X-ray light can be explained by gravitational
microlensing, an effect which has been used to search for compact
stars and
planets in our galaxy. Microlensing occurs when a star or a multiple star system passes in front of light from a background object. If a single star or a multiple star system in one of the foreground galaxies passed in front of the light path for the brightest image, then that image would be selectively magnified.
Black hole The X-rays would be magnified much more than the
visible light if they came from a region around the central
supermassive black hole of the lensing galaxy that was smaller than the origin region of the visible light. The enhancement of the
X-rays from
iron ions would be due to this same effect. The analysis indicates that the X-rays are coming from a very small region, about the size of the
Solar System, around the central black hole. The visible light is coming from a region ten or more times larger. The angular size of these regions at a distance of 11 billion
light years is tens of thousands times smaller than the smallest region that can be resolved by the Hubble Space
Telescope. This provides a way to test models for the flow of gas around a supermassive black hole.
Lensing galaxy and partial Einstein ring Data from
NICMOS and a special
algorithm resolved the lensing galaxy and a partial
Einstein ring. The Einstein ring represents the host galaxy of the lensed quasar. == History ==