Earth-sized

The Kepler spacecraft will watch a patch of space for 3.5 years or more for signs of Earth-sized planets moving around stars similar to the sun.

NASA Watch: March 2009 Archives 2009

Sixty-eight of the planet candidates Kepler found are considered Earth-sized, including the first ones ever discovered to be smaller than Earth.

NASA Spots 54 Potentially Life-Friendly Planets AP 2011

That it might be possible to detect an Earth-sized exoplanet and then learn about the basic chemical makeup of that world illustrates just how far space science and technology have gone.

First Contact Marc Kaufman 2011

"This is the first time that humanity has been able to detect another Earth or Earth-sized object around another star."

Astronomers Spot Distant Earth-Size Planets Robert Lee Hotz 2011

Especially so, now that respected astronomers like Geoff Marcy and Andrew Howard have extrapolated from their planet-hunting data that tens of billions of Earth-sized planets exist in the Milky Way alone.

First Contact Marc Kaufman 2011

So the big question for planet hunters is no longer simply how to find planets, but rather how to find more of the smaller, rocky, Earth-sized planets the right distance from their suns to be potentially habitable, and to find solar systems structured in ways that could allow these cousins of the Earth to become nurseries for life.

First Contact Marc Kaufman 2011

In fact, based on observations at the same Keck Observatory, Marcy and his University of California at Berkeley partner Andrew Howard concluded that Earth-sized planets are absolutely common in the universe.

First Contact Marc Kaufman 2011

Not all, and probably not most, Earth-sized planets are actually like Earth.

First Contact Marc Kaufman 2011

In terms of scale, some have compared the feat of detecting an Earth-sized exoplanet to reading the mint date on a dime at a distance of more than three miles.

First Contact Marc Kaufman 2011

This is not necessarily a majority view, because the technical challenges of finding Earth-sized planets remain daunting, and the best approaches now possible cannot definitively locate a planet the size of our ball of rock.

First Contact Marc Kaufman 2011