Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. 24/7 Space News .




EXO WORLDS
'17 billion' Earth-sized planets in Milky Way: study
by Staff Writers
Washington (AFP) Jan 7, 2013


The Milky Way contains at least 17 billion planets the size of Earth, and likely many more, according to a study out Monday that raises the chances of discovering a sister planet to ours.

Astronomers using NASA's Kepler spacecraft found that about 17 percent of stars in our galaxy have a planet about the size of Earth in a close orbit.

The Milky Way is known to host about 100 billion stars, meaning that about one of every six has an Earth-sized planet around it.

The finding does not mean that all those planets beyond our solar system, or exoplanets, could be habitable, though it increases the chances of finding planets similar to Earth.

In order to host life, and allow water to flow in liquid form, a planet must be at a distance from its star that allows surface temperatures to be neither too hot nor too cold.

The Kepler craft detected possible exoplanets when they passed in front of their star, creating a mini-eclipse that dims the star slightly.

During the first 16 months of the survey, Kepler identified about 2,400 candidates.

Francois Fressin, of the Harvard-Smithsonian Center for Astrophysics, and his colleagues used the results to determine which signals were true and to list the exoplanets by size.

They found that 17 percent of stars have a planet 0.8 to 1.25 times the size of Earth in an orbit of 85 days or less.

About a fourth of stars have a super Earth (1.25 to twice the size of Earth) in an orbit of 150 days or less, with a same fraction having a mini Neptune (two to four times Earth) in orbits up to 250 days long.

Larger planets are a much rarer occurrence. Only about three percent of stars have a large Neptune (four to six times Earth) and only five percent have a gas giant (six to 22 times Earth) in an orbit of 400 days or less.

The researchers presented the analysis at a meeting of the American Astronomical Society in Long Beach, California.

Separately, NASA's Kepler mission announced it had discovered 461 new possible planets.

Four of them are less than twice the size of Earth and orbit their sun's "habitable zone," where liquid water might exist on the planet's surface and thus make life possible.

The findings, based on observations conducted from May 2009 to March 2011, showed the number of smaller-size planet candidates and the number of stars with more than one candidate steadily rising.

.


Related Links
Lands Beyond Beyond - extra solar planets - news and science
Life Beyond Earth






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





EXO WORLDS
NASA Kepler hints at over 250 new potentially habitable worlds
Arecibo PR (SPX) Jan 07, 2013
NASA Kepler released last month 18,406 planet-like detection events from its last three year mission to search for exoplanets (Kepler Q1-Q12 TCE). Further analysis is required by the NASA Kepler Team and the scientific community to extract and identify true planets, including those potentially habitable. The Planetary Habitability Laboratory @ UPR Arecibo (PHL) performed a preliminary anal ... read more


EXO WORLDS
Mission would drag asteroid to the moon

Russia designs manned lunar spacecraft

GRAIL Lunar Impact Site Named for Astronaut Sally Ride

NASA probes crash into the moon

EXO WORLDS
'Black Beauty' could yield Martian secrets

India scales down experimental flying payloads for exploring Mars

Ancient Water-rich Meteorite Linked to Martian Crust

Stanford researchers develop acrobatic space rovers to explore moons and asteroids

EXO WORLDS
2012 in Polish space activities

Captain's log: real space chat for Star Trek crew

Congress Approves Bill Supporting Human Space Exploration

China's Chengdu aiming to be world's next Silicon Valley

EXO WORLDS
Mr Xi in Space

China plans manned space launch in 2013: state media

China to launch manned spacecraft

Tiangong 1 Parked And Waiting As Shenzhou 10 Mission Prep Continues

EXO WORLDS
Crew Wraps Up Robonaut Testing

Station Crew Ringing in New Year

Expedition 34 Ready to Ring in New Year

New ISS crew docked at Space Station

EXO WORLDS
Arianespace to launch VNREDSat-1A built by Astrium for Vietnam

Arianespace says 2012 sales leapt by 30%

CSF Applauds Passage Of Risk-Sharing Regime Extension For Launch Industry

Rokot Launch Set for January 15

EXO WORLDS
'17 billion' Earth-sized planets in Milky Way: study

Astrophysicists find wide binary stars wreak havoc in planetary systems

NASA Kepler hints at over 250 new potentially habitable worlds

Billions and Billions of Planets

EXO WORLDS
That's not what I meant: A new phase in reading photons

Space Trash May Make Radiation Shields

Reservoir Labs Selected For The DARPA Power Efficient Computing Research And Development Program

Liquid jets and bouncing balls combine for surprising results




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement