Sci/Tech

Earth-size planet found with rocky core like ours

CAPE CANAVERAL, Florida (AP) — Scientists have found a planet way out in the cosmos that's close in size and content to Earth — an astronomical first.

But this rocky world is so close to its sun that it's almost certainly too hot for life. Astrophysicists reported Wednesday in the journal Nature that the exoplanet Kepler-78b appears to be made of rock and iron, just like Earth. They measured the planet's mass to determine its density and content. It's actually a little bigger than Earth and nearly double its mass, or weight.

Kepler-78b is located in the Cygnus constellation hundreds of light-years away. Incredibly, it orbits its sun every 8½ hours, a mystery to astronomers who doubt it could have formed or moved that close to a star. They agree the planet will be sucked up by the sun in a few billion years, so its time remaining, astronomically speaking, is short.

More than 1,000 exoplanets — worlds outside our solar system — have been confirmed so far. NASA's Kepler Space Telescope, used to discover Kepler-78b, has identified 3,500 more potential candidates. The telescope lost its precise pointing ability earlier this year, and NASA has given up trying to fix it.

Scientific teams in the United States and Switzerland used ground observatories to measure Kepler-78b.

Related Headlines

  • Vast ocean found beneath ice of Saturn moon

    Scientists have uncovered a vast ocean beneath the icy surface of Saturn's little moon Enceladus. Italian and American researchers made the discovery using Cassini, a ... 

  • Titan

    Holiday lights: New views of Saturn and its moons

    A NASA spacecraft has sent holiday greetings from the outer solar system. The space agency on Monday released dazzling new images of the ringed planet Saturn and its moons. 

  • 2018 mission: Mars rover prototype unveiled in UK

    It looks like a giant sandbox — except the sand has a reddish tint and the "toys" on display are very expensive prototypes designed to withstand the rigors of landing on Mars. 

  • K. Radhakrishnan

    India launches first mission to Mars

    India on Tuesday launched its first spacecraft bound for Mars, a complex mission that it hopes will demonstrate and advance technologies for space travel. Hundreds of people ...