In Brief:

May 30, 2000
Web posted at: 5:29 p.m. EDT (2129 GMT)

From staff reports

(CNN) -- A team of scientists has measured thermal variations on Pluto, proving that the temperature on the distant planet is not uniform, the European Space Agency said this week.

The coldest regions on the planet plummet to a temperature of about -235 degrees C (-391 F). The hottest may reach a sizzling -210 degrees C (-346 F).

Pluto is the planet with the farthest mean distance from the center of the solar system. Along with its slightly smaller satellite Charon, it orbits the sun from a distance of 3,700 million miles (5,900 million kilometers).

The two bodies also circle around a common center of gravity every 6.4 days. Using the ESA's infrared space telescope ISO, a team from the Observatoire de Paris determined that the planet system emits more thermal energy at some times compared to others.

Additionally, the flux corresponds with contrasting brightness of different parts of the surface of Pluto. The darker regions absorb more solar energy and therefore warm up more and give off more infrared energy, the scientists said.

The observations suggest that the material in the darker regions is porous, the ESA team said.

Want more? Go to previous In Brief