New York, Aug 6 (IANS): Astronomers have discovered an extremely cool planet-like object that may have spent much of its youth as hot as a star.
The current surface temperature of the object is 100-150 degrees Celsius that is intermediate between that of the Earth and of Venus.
However, the object shows evidence of a possible ancient origin, implying that a large change in temperature has taken place.
In the past, this object would have been as hot as a star for many millions of years.
Called WISE J0304-2705 and part of "Y dwarf" family, it is dissimilar to the rocky Earth-like planets and instead is a giant ball of gas like Jupiter.
The Y dwarf was identified using the WISE observatory - NASA space telescope that has imaged the entire sky in the mid-infrared.
Only 20 other Y dwarfs have been discovered to-date.
"This discovery poses ongoing challenges for the most powerful modern telescopes that are being used for its detailed study," said Maria Teresa Ruiz, a team member from the Universidad de Chile.