thenewenlightenmentage:

Two Earth-Size Planets Born of Battered “Jupiter”?

Worlds orbiting a dying star may be pieces of a broken gas giant, study hints.

Ker Than

for National Geographic News

Published February 10, 2012

Two Earth-size worlds orbiting perilously close to their dying star may be the fractured remnants of a Jupiter-like gas giant, a new study suggests.

The planetary pair—discovered using NASA’s Kepler space telescope and announced in the journal Nature last December—are just under Earth’s radius. Both orbit a so-called subdwarf B star dubbed KIC 05807616, which sits about 4,000 light-years away.

(Also see “Smallest Exoplanets Found—Each Tinier Than Earth.”)

When sunlike stars run out of hydrogen fuel, they enter a red giant phase, in which their gas envelopes can swell to several hundred times their original size.

Eventually a red giant’s gas envelope will slough off entirely, leaving behind a dense stellar corpse known as a white dwarf. Sometimes, however, a red giant will lose its gas envelope prematurely to form a subdwarf B star, like KIC 05807616.

Read More

thenewenlightenmentage:

Two Earth-Size Planets Born of Battered “Jupiter”?

Worlds orbiting a dying star may be pieces of a broken gas giant, study hints.

Ker Than

for National Geographic News

Published February 10, 2012

Two Earth-size worlds orbiting perilously close to their dying star may be the fractured remnants of a Jupiter-like gas giant, a new study suggests.

The planetary pair—discovered using NASA’s Kepler space telescope and announced in the journal Nature last December—are just under Earth’s radius. Both orbit a so-called subdwarf B star dubbed KIC 05807616, which sits about 4,000 light-years away.

(Also see “Smallest Exoplanets Found—Each Tinier Than Earth.”)

When sunlike stars run out of hydrogen fuel, they enter a red giant phase, in which their gas envelopes can swell to several hundred times their original size.

Eventually a red giant’s gas envelope will slough off entirely, leaving behind a dense stellar corpse known as a white dwarf. Sometimes, however, a red giant will lose its gas envelope prematurely to form a subdwarf B star, like KIC 05807616.

Read More