An artist's impression of a planet orbiting very close to its parent star
A Nasa space observatory launched in March this year has observed a planet circling another star.
In a test of its capability, the orbiting Kepler telescope detected the planet's atmosphere.
Kepler will survey our region of the Milky Way for Earth-sized planets which might be capable of supporting life.
The telescopes first findings are based on 10 days of data collected before the start of official science operations.
The results have been published in the journal Science.
The observations are of a planet called HAT-P-7, known to transit a star located about 1,000 light-years from Earth.
This distant world orbits its star in just 2.2 days and is 26 times closer than Earth is to the Sun.
The light curve from the planet reveals that its atmosphere has a day-side temperature of about 2,377C (4,310F).
"This early result shows the Kepler detection system is performing right on the mark," said David Koch, deputy principal investigator of Nasa's Ames Research Center in California.