Kepler Detects Potential Evaporating Planet

The artist’s concept depicts a comet-like tail of a possible disintegrating super Mercury-size planet candidate as it transits its parent star named KIC 12557548. At an orbital distance of only twice the diameter of its star, the surface temperature of the potential planet is estimated to be a sweltering 3,300 degrees Fahrenheit. At such a high temperature, the surface would melt and evaporate. The energy from the resulting wind would be enough to allow dust and gas to escape into space, creating a trailing dusty effluence that intermittently blocks the starlight. Courtesy of NASA/JPL-Caltech

Astronomers may have detected evidence of a possible planet disintegrating under the searing heat of its host star located 1,500 light-years from Earth. Similar to a debris-trailing comet, the super Mercury-size planet candidate is theorized to fashion a dusty tail. But the tail won’t last for long. Scientists calculate that, at the current rate of evaporation, the dusty world could be completely vaporized within 200 million years.

A research team led by Saul Rappaport, professor emeritus of physics at MIT, has identified an unusual light pattern emanating from a star named KIC 12557548 in the Kepler space telescope’s field-of-view.

NASA’s Kepler space telescope detects planets and planet candidates by measuring dips in the brightness of more than 150,000 stars to search for planets crossing in front, or transiting, their stars.

“The bizarre nature of the light output from this star with its precisely periodic transit-like features and highly variable depths exemplifies how Kepler is expanding the frontiers of science in unexpected ways,” said Jon Jenkins, Kepler co-investigator at the SETI Institute in Mountain View, CA. “This discovery pulls back the curtain of how science works in the face of surprising data.”

Orbiting a star smaller and cooler than our sun, the planet candidate completes its orbit in less than 16 hours — making it one of the shortest orbits ever detected. At an orbital distance of only twice the diameter of its star, the surface temperature of the planet is estimated to be a smoldering 3,300 degrees Fahrenheit.

Scientists hypothesize that the star-facing side of the potentially rocky inferno is an ocean of seething magma. The surface melts and evaporates at such high temperatures that the energy from the resulting wind is enough to allow dust and gas to escape into space. This dusty effluence trails behind the doomed companion as it disintegrates around the star.

Additional follow-up observations are needed to confirm the candidate as a planet. The finding is published in The Astrophysical Journal and is available for download at: http://arxiv.org/abs/1201.2662 

For more details on the finding visit: http://web.mit.edu/newsoffice/2012/dusty-exoplanet-0517.html

For more information about the Kepler mission, visit: http://www.nasa.gov/kepler