Explanation:
HD 189733b is a Jupiter-sized
planet
known to orbit a star some 63 light-years away.
But while the distant world is approximately the size of Jupiter, its
close-in orbit makes it much hotter than our solar system's ruling
gas giant.
Like other detected
hot Jupiters,
its rotation is tidally
locked -- one side always faces its parent star as it orbits
once every 2.2 days.
Using infrared
data from the
Spitzer Space Telescope,
this planet's temperature variations have been mapped out
-- the first map ever made
for a planet beyond our solar system.
Seen here (brighter colors = higher temperatures),
the hottest spot on the planet is not at longitude 0.0, the point
exactly facing the parent star.
Instead, it's about 30 degrees to the east (right), evidence that
fierce, planet circling winds influence the temperature.
In the planet-wide map,
the temperature measurements vary from about
930 to 650 degrees C (1,700 to 1,200 F).