Астронет: Астрономическая картинка дня Сеть каустик микролинзирования http://variable-stars.ru/db/msg/1162965/eng |
Credit & Copyright: Joachim Wambsganss
(Ap. Inst. Potsdam)
Explanation:
A virtual sky map like this would be of interest
to astronomers studying gravitational microlensing.
In microlensing, the gravity of stars near the line of sight
can act to magnify the light of background objects such as
distant stars, or
quasars.
Nowhere is this magnification greater
than near a gravitational lensing
caustic.
In the
above computer simulated map,
caustics are discernible as the sharp bright curved lines.
When a background
quasar
moves across a microlensing caustic,
it can appear
dramatically brighter.
Many astronomers thought
microlensing events practically
immeasurable even ten years ago,
but within the past five years now
hundreds have been found.
Precise measurements of microlensing are now
providing unique information about the
composition and distribution of matter in
galaxies and the
universe.
Some astronomers now predict that future
microlensing searches might even
isolate planets orbiting distant stars.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.