The planet is affected by the high stellar activity

Sep 18, 2013 17:21 GMT  ·  By
Artist impression of KIC 12557548b evaporating under the influence of its star
   Artist impression of KIC 12557548b evaporating under the influence of its star

Plenty of exoplanets have been found very close to their parent stars. These planets are easier to spot with current detection methods, so we've discovered quite a lot of them. But living life on the edge like this can take its toll on some planets.

KIC 12557548b, a super Mercury-size planet, is fast losing mass under the influence of its parent star.

The star is highly active and the massive flares erupting from it affect the planet. Scientists believe the exoplanet is fast losing mass leaving a trail of dust behind it in its orbit around the star.

Looking at the data from Kepler, the researchers from the University of Tokyo also determined that the rate at which the planet loses material directly correlates with star activity, i.e. it loses more material and thus obscures a larger area of the star when it passes in front of a stellar spot, an area of high activity.

The stellar spots on this star are much larger than the ones on our sun and last for longer as well. In fact, they've helped astronomers determine the rotation period of the star.

“Energy from the star spots increases the amount of dust and atmosphere from the planet,” Dr. Hajime Kawahara, the lead author of a recent paper on the planet, told Universe Today.

“The extreme heat and wind is enough to speed up the motions of the dust molecules; making them fast enough to escape the planet’s gravitational pull,” he added.

The planet is estimated to weigh about 0.1 Earth masses. Any bigger than that and its gravity would mean it would lose less material, and any smaller and it would have been already gone.

Astronomers estimate that the planet will completely vanish within 100 to 200 million years.