Unlike the Hubble Space Telescope, which is a general instrument, Kepler is a specialized telescope just for planet-hunting. Its sole instrument is a light meter that measures the brightness of more than 100,000 stars simultaneously, watching for anything that causes a star to dim. That dimming is often a planet passing in front of the star. Any planet that could support life would need to be rocky rather than gaseous. And it would need to be in just the right location. Planets that are too close to their star will be too hot, and those too far away are too cold.

Planets are being found on almost a daily basis, thanks to the Kepler telescope. The number of discovered exoplanets is now well past 400. But none of those has the right components for life. Most of the early exoplanet candidates found by Kepler are turning out to be something other than a planet, such as another star crossing the telescope’s point of view, when double-and triple-checked. Kepler is concentrating on about one-four hundredth of the nighttime sky, scanning more than 100,000 stars, ranging from a few hundred to a few thousand light years away. A light year is about 5.9 trillion miles. So such planets are too far to travel to, and they cannot be viewed directly like the planets in our solar system.

If there were an Earth-like body in the area Kepler is searching, the telescope would find it, but it can take three years to confirm a planet’s orbital path. What Kepler has confirmed so far keeps pointing to the idea that there are many other Earths. Before Kepler, those bodies were too small to be seen. But all those planets were too large and in the wrong place to be like Earth. When Kepler looked at 43,000 stars that are about the same size as our sun, it found that about two-thirds of them appeared to be as life-friendly and nonviolent as our nearest star.

Excited astronomers say they could find Earth-like planets in just a few years and state they are on the verge of finding NASA officials and other leading scientists state that within four or five years they should discover the first Earth-like planet where life could develop, or may have already. A planet close to the size of Earth could even be found sometime this year if preliminary hints from a new space telescope pan out. Planets like Earth orbiting other stars, a key step in determining if we are alone in the universe. A massive space telescope to scan Earth-like planets for oxygen, water, carbon dioxide – and even faint signs of industrial emissions from civilization – would cost about $5 billion. Once an Earth-like planet is found in the right place, determining if there are the ingredients for life there will pose another hurdle.

Even the Roman Catholic Church has held scientific conferences about the prospect of extraterrestrial life, including a meeting last November. The director of the Vatican Observatory, the Rev. Jose Funes stated these are big questions that reflect upon the meaning of the human race in the universe.

Further inforamtion can be found on the web: NASA’s Kepler Telescope: http://kepler.nasa.gov/ ; NASA’s Exoplanet Exploration Program: http://exep.jpl.nasa.gov/ ; The Extrasolar Planets Encyclopaedia: http://www.exoplanet.eu/ ; and American Astronomical Society: http://aas.org/