On the edge of our solar system, dwarf planet Pluto is becoming increasingly red, said Nasa scientists.(photo, from bbc.co.uk)
The Hubble space telescope took images showing that the planet is some 20% redder than it used to be.
According to experts, this is because of changes in Pluto’s surface ice, as it enters a new phase of its 248-year-long orbit.
The new images are said to show frozen nitrogen brightening in the north and becoming darker in the south.
“These changes are most likely consequences of surface ice melting on the sunlit pole and then re-freezing on the other pole,” Nasa’s Space Telescope Science Institute said in a statement.
Yet some astronomers have expressed shock at the changes. “It’s a little bit of a surprise to see these changes happening so big and so fast,” said Marc Buie, of the Southwest Research Institute. “This is unprecedented.”
Pluto was stripped of its status as a full planet by astronomers in 2006, and was downgraded to a dwarf planet.
In our system solar Pluto is farther away and considerably smaller than the eight other “traditional” planets. At just 2,360km (1,467 miles) across – Pluto is smaller even than some moons.
However the red tinge is not thought to have had a marked effect on the planet’s temperature: despite any redness, Pluto’s surface temperature remains incredibly cold at -233C (-382F).