Another planet in our solar system

A newly discovered dark and frigid world, a bit smaller than Pluto and three times farther away, has emerged as the most distant object in the solar system, astronomers said on Monday. The new ‘‘planetoid’’, named Sedna after an Inuit goddess who created the sea creatures of the Arctic, is by far the coldest and most distant object known to orbit the Sun, a team of researchers announced.

At more than 13 billion km from the sun, the temperature on Sedna never gets above minus 240 Celsius. ‘‘The sun appears so small from that distance that you could completely block it out with the head of a pin,’’ said Mike Brown, an astronomer at California Institute of Technology, who led the research team. It was first detected on November 14 with the Samuel Oschin Telescope near San Diego, California. NASA’s new orbiting Spitzer Space Telescope, which looks at the universe with infrared detectors that peer through cosmic dust, was also trained on the distant object. The Spitzer scope found that Sedna probably has about three-fourths the diameter of Pluto, which would make it the biggest object found in the solar system since Pluto’s discovery in 1930. — (Reuters)