Subscribe free to our newsletters via your
. 24/7 Space News .




EXO WORLDS
Three Earthlike planets identified by Cornell astronomers
by Anne Ju for Cornell News
Cornell NY (SPX) Apr 27, 2012


The Kepler mission continuously monitors 150,000 stars for transit signals - a dip in the star's brightness due to the passing of a planet. The Cornell team narrowed the list to 80 stars with these signals, focusing on stars called M dwarfs. These are smaller, dimmer stars than our sun, but the majority of the stars in the universe are M dwarfs, the researchers said.

It's not little green men, but it could be a step in that direction: Cornell astronomers, using data from the NASA Kepler Mission, have identified three Earthlike planets orbiting their own suns, all of which could be hospitable to life.

The team of astronomers used the Cornell-built Near-Infrared Triple Spectrograph (TripleSpec) at California's Mount Palomar Observatory to measure the temperatures and metallicities of small stars called M dwarfs, first recorded by the NASA Kepler mission, which then led to observations of planets orbiting these stars.

Kepler launched in 2009 to search for planets outside our solar system, which are called extrasolar planets or exoplanets. The team that built TripleSpec, completed in 2008, was led by Terry Herter, Cornell professor of astronomy.

The findings were published online in Astrophysical Journal Letters (Vol. 750, No. 2). The discovery could lead to better studies of these planets and pave the way toward discovering planets just like Earth.

The three planets orbit within their host stars' "habitable zones" - the orbital distance in which liquid water could exist, and the sweet spot for determining whether life could be possible.

The host stars - KOI (Kepler Object of Interest) 463.01, KOI 812.03 and KOI 854.01 - are located in areas of the sky between the constellations Cygnus and Lyra, in the range of a few hundred to a few thousand light years away.

"There is a fairly solid argument that the vast majority of planets in the universe, and quite possibly the Earthlike habitable zone planets, are planets orbiting M dwarfs," said Jamie Lloyd, associate professor of astronomy and mechanical and aerospace engineering, and paper co-author.

The Kepler mission continuously monitors 150,000 stars for transit signals - a dip in the star's brightness due to the passing of a planet. The Cornell team narrowed the list to 80 stars with these signals, focusing on stars called M dwarfs. These are smaller, dimmer stars than our sun, but the majority of the stars in the universe are M dwarfs, the researchers said.

"These stars are super faint in the visible wavelengths, neglected for years" because they are notoriously hard to characterize, said paper co-author Barbara Rojas-Ayala, Ph.D. '12, now a researcher at the American Museum of Natural History.

While at Cornell, Rojas-Ayala developed a technique using TripleSpec to measure metallicities and temperatures of M dwarf stars. The Cornell team used this technique to identify the same parameters for the 80 M-dwarf stars. Using data from TripleSpec combined with theoretical models of how these types of stars probably evolved over time, they obtained the sizes of these 80 stars.

TripleSpec gave the researchers more accurate measurements of the stars' characteristics than originally obtained by the Kepler mission. And around these stars, they identified three Earthlike planet candidates based on their relative size, mass and temperature compared with Earth, the likelihood of having a rocky surface and their presence in their stars' habitable zone.

"Seventy percent of the stars in the universe are these small stars, not like our sun," said Philip Muirhead, Ph.D. '11, now a researcher at California Institute of Technology. "So if these planets are common around small stars, and small stars are common in the universe, then most life in the universe may in fact exist around these types of planets, and not around Earthlike systems and sunlike stars."

Astronomers call planets "candidates" until follow-up studies confirm them as planets; the Cornell researchers hope their work will inspire other scientists to point their telescopes in the direction of these new planet candidates.

For example, said Muirhead, astronomers might study these planets' atmospheres using space telescopes like Hubble or the James Webb Space Telescope, and look for biosignatures, like oxygen absorption lines.

"If we saw signatures of oxygen in these planets' atmospheres, that would be a major step toward identifying extraterrestrial life in the universe," Muirhead said.

.


Related Links
Cornell
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
Some Stars Capture Rogue Planets
Boston MA (SPX) Apr 20, 2012
New research suggests that billions of stars in our galaxy have captured rogue planets that once roamed interstellar space. The nomad worlds, which were kicked out of the star systems in which they formed, occasionally find a new home with a different sun. This finding could explain the existence of some planets that orbit surprisingly far from their stars, and even the existence of a double-pla ... read more


EXO WORLDS
Moon Express Delivers Lunar Mission Design Report for mining the Moon for precious resources

NASA's Lunar Reconnaissance Orbiter Brings 'Earthrise' to Everyone

Winners of 19th Annual NASA Great Moonbuggy Race Announced

Russian Space Agency eyes Moon explorations

EXO WORLDS
Martian Volcanic Glass Could Be Hotspot for Life

Mars Express explores the roots of Martian volcanoes

Lava flows carved Mars valleys: study

Mars Astronauts Could Risk DNA Damage

EXO WORLDS
Space -- the next frontier for Hillary Clinton?

Company to Create 'Gas Stations' in Space

Boeing, NASA Sign Agreement on Mission Support for CST-100

Parachutes for NASA crew capsule tested

EXO WORLDS
China's Lunar Docking

Shenzhou-9 may take female astronaut to space

China to launch 100 satellites during 2011-15

Three for Tiangong

EXO WORLDS
Three astronauts to land from ISS Friday

Expedition 30 Crew Returning Home Friday

Russia brings three spacemen safely back to Earth

Three astronauts land on Earth from ISS in Russian capsule

EXO WORLDS
Indian rocket being fuelled for Risat-1 launch

Assembly begins for the third Ariane 5 to be launched in 2012

ILS Proton Successfully Launches Y1B Satellite For Yahsat

SpaceX aims for May 7 launch to ISS

EXO WORLDS
Three Earthlike planets identified by Cornell astronomers

Some Stars Capture Rogue Planets

ALMA Reveals Workings of Nearby Planetary System

UF-led team uses new observatory to characterize low-mass planets orbiting nearby star

EXO WORLDS
I like to break things

Beyond stain-resistant: New fabric coating actively shrugs off gunk

Scientists Predict Paradoxical Laser Effect

Japan, Kazakhstan to jointly develop rare earths: report




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