Astronomy

2 Billion Alien Earths Estimated to Exist in our Galaxy



Tweet
Terrence Aym's image for:
"2 Billion Alien Earths Estimated to Exist in our Galaxy"
Caption: 
Location: 
Image by: 
©  

The U.S. National Aeronautics and Space Administration (NASA) has revised its earlier estimates of Earthlike worlds in our galaxy. Now the space agency believes up to 2 billion such planets exist.

Stating that about one of every 37 to 70 type-G stars (suns like our own) might support alien life has significantly raised the possibility of a universe teeming with intelligent life.

A new study from NASA's Pasadena, California Jet Propulsion Laboratory (JPL) reports that more than 1,200 alien planets—up to 68 of them Earthlike—have been discovered by the remarkable Kepler space telescope.

The landmark study, "The Occurrence Rate of Earth Analog Planets Orbiting Sunlike Stars," has been published online by the Astrophysical Journal.

Excited scientists at JPL narrowed their observations to planets that have similarities to Earth. They sought out probable habitable zones in regions of the galaxy where earth-like worlds would most likely be found orbiting stars having the same physical qualities as our sun. One of the criteria they used: liquid water must be possible on the planets.

Following an intensive four month analysis of the reams of data that Kepler churned out, JPL came to the conclusion that that 1.4 to 2.7 percent of stars like ours probably have Earthlike worlds orbiting them.

Asked by SPACE.com about the astonishing findings, Joseph Catanzarite, an astronomer at NASA's Jet Propulsion Laboratory responded, "This means there are a lot of Earth analogs out there—two billion in the Milky Way galaxy. With that large a number, there's a good chance life and maybe even intelligent life might exist on some of those planets.

The revelation has large implications for the future of Mankind, space exploration, and the place of humans in the universe.

"And that's just our galaxy alone—there are 50 billion other galaxies," Catanzarite added.

Goldilocks zone

NASA has been actively seeking planets in the Milky Way galaxy that fall withing the so-called "Goldilocks zone." Those worlds would be not too hot, not too cold, and like the porridge in the children's story of "Goldilocks and the Three Bears" would be just right. Other that temperature, the planets would have to support an atmosphere with enough pressure, and have enough mass so things wouldn't go flying off into space while not so much mass that things would be crushed from intense gravity.

Astronomers at JPL have predicted they would find about 12 Goldilock worlds. So far, four have been identified during the last four months of sifting through the space telescope's data.

The Kepler astronomers emphasize as many as 50 billion planets of all types exist in our galaxy. Of those, most are thought to be uninhabited and uninhabitable for a variety of reasons.

Tweet
More about this author: Terrence Aym

From Around the Web




ARTICLE SOURCES AND CITATIONS
  • InfoBoxCallToAction ActionArrowhttp://arxiv.org/ftp/arxiv/papers/1103/1103.1443.pdf
  • InfoBoxCallToAction ActionArrowhttp://www.space.com/11188-alien-earths-planets-sun-stars.html
  • InfoBoxCallToAction ActionArrowhttp://www.linkedin.com/pub/joseph-catanzarite/0/b43/b89