"Tens of billions" of habitable worlds in Milky Way

LONDON Wed Mar 28, 2012 8:17am EDT

This artist's impression shows a sunset seen from the super-Earth Gliese 667 Cc. REUTERS/ESO/L. Calçada/Handout

This artist's impression shows a sunset seen from the super-Earth Gliese 667 Cc.

Credit: Reuters/ESO/L. Calçada/Handout

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LONDON (Reuters) - Astronomers hunting for rocky planets with the right temperature to support life estimate there may be tens of billions of them in our galaxy alone.

A European team said on Wednesday that about 40 percent of red dwarf stars - the most common type in the Milky Way - have a so-called "super-Earth" planet orbiting in a habitable zone that would allow water to flow on the surface.

Since there are around 160 billion red dwarfs in the Milky Way, the number of worlds that are potentially warm enough and wet enough to support life is enormous.

Xavier Bonfils of the Institute of Planetology and Astrophysics in Grenoble, the leader of the team, said the 40 percent figure was at the high end of what had been expected and the finding underscored the prevalence of small rocky planets.

His team is the first to calculate the number of super-Earths - planets with a mass between one and 10 times the Earth - in such habitable zones, although previous research has found the Milky Way to be awash with planets.

Red dwarfs, which are faint and cool compared to the Sun, account for around 80 percent of the stars in the Milky Way.

After studying 102 of these stars in the southern skies using a European Southern Observatory telescope in Chile, Bonfils and colleagues found rocky planets were far more common than massive gas giants like Jupiter and Saturn in our solar system.

However, the rocky worlds spinning around red dwarfs are not necessarily cosy places for alien forms of life.

Because reds dwarfs are much cooler than the sun, any planets with liquid water will need to be orbiting much closer to the star than the Earth is from the Sun. That may mean they are bathed in damaging X-ray and ultraviolet radiation.

Scientists aim to take a closer look at some of the Earth-like planets as they pass in front of nearby red dwarfs, which should yield information about their atmospheres and help in the search for possible signs of life.

The research was presented in a paper to be published in the journal Astronomy & Astrophysics link.reuters.com/bav37s

(Editing by Michael Roddy)

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Comments (15)
bobber1956 wrote:
Oh yeah, been to any lately?

Mar 28, 2012 8:56am EDT  --  Report as abuse
gregbrew56 wrote:
Bobber1956: Been to Paris lately? Me neither, but I’m pretty confident it exists, too!

Educate yourself.

Mar 28, 2012 11:12am EDT  --  Report as abuse
Alpha108 wrote:
This again proves the theory of “OM”. Initially, there was nothing in the entire universe. Then the Paramatma Almighty supreme power did a Sankalp to become in many forms -and thus a spandan [vibration] of “Pranav” mantra of “OM” was created which in turn created this universe, living and non-living things. If we see carefully, the same divine power and thread represented by OM runs through every planet, living being and non-living being. What we need is to realise the divinity within via good work and good deeds.

Sooner or later, the world will have to recognise the knowledge and information concentrated in 4 Vedas, Upanishad, Purans, Gita, Mahabharata, Ramayana and many other manuscripts.

OM Shanti.

Mar 28, 2012 11:21am EDT  --  Report as abuse
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