These computer-generated images chart the development of severe weather
patterns on the highly eccentric exoplanet HD 80606b during the days after
its closest approach to its parent star. An exoplanet is a planet that
orbits a star other than our sun.
The images were produced by computer simulations that modeled NASA's
Spitzer Space Telescope's measurements of heat radiating from the planet.
The six frames are evenly spaced in time, starting from 4.4 days after the
planet's close approach to the star, a moment known as "periastron," and
running through 8.9 days after periastron. The blue glow of the crescent
is starlight that has been scattered and reflected by the planet. The
starlight appears blue because the planet is a very efficient absorber of
red light. The night side appears reddish orange as it glows with its own
internal heat.
These theoretical models allow astronomers to better understand weather
patterns on distant planets. While direct telescopic observations of the
atmospheres of such worlds may be many decades away, such simulations give
us a clue to what we may see when it becomes possible.
The Spitzer observations themselves spanned the relatively brief period
when the heating of the planet was most intense, running from 20 hours
prior to 10 hours after periastron. The data were taken in Nov. of 2007.
HD 80606b is located 190 light-years away in the constellation Ursa Major.
Its star can be seen with binoculars.