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Астронет: Астрономическая картинка дня В тени исторической планеты http://www.variable-stars.ru/db/msg/1162849/eng |
Credit & Copyright: Lynette Cook
Explanation:
For the first time, astronomers have recovered independent evidence that
distant planetary systems exist.
Last Friday, a team led by
G. W. Henry
(Tenn. State) and
G. Marcy
(UC Berkeley)
announced
the discovery of a shadow of a
planet crossing a distant star.
Little known
HD 209458, a Sun-like star 150 light-years away,
had been suspected of harboring planets from a slight
wobble found in its motion.
Henry et al. now find that
this wobble exactly corresponds to a
planet crossing the face of the star,
creating the slight dimming effect of a
partial eclipse.
The astronomers were then able to make a
groundbreaking estimate of the mass and radius of the
extra-solar planet,
which they find to have about two-thirds the mass of
Jupiter but about 60 percent larger radius.
The drawing above is an artist's depiction of a
planetary eclipse in the HD 209458 system.
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.