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

Exo planets that survived red giant stage found
by Staff Writers
Ames, IA (SPX) Dec 22, 2011

This shows two planets that survived the red-giant expansion of their host star. Credit: Illustration by Stephane Charpinet/Institut de Recherche en Astrophysique et Planetologie in Toulouse, France.

Astronomers have discovered two Earth-sized planets that survived getting caught in the red-giant expansion of their host star. Steve Kawaler, an Iowa State University professor of physics and astronomy and a leader of the Kepler Asteroseismic Investigation, helped the research team study data from the Kepler space telescope to confirm that tiny variations of light from a star were actually caused by two planets of that star.

The findings are published in the Letters section of the Dec. 22 edition of the journal Nature. Stephane Charpinet of the Institut de Recherche en Astrophysique et Planetologie in Toulouse, France, is the lead author and leader of the research team.

"This is a snapshot of what our solar system might look like after several billion more years of evolution," Kawaler said. "This can help us learn about the future of planetary systems and of our own sun."

Kawaler said the researchers have studied pulsations of the planets' host star (KIC 05807616, an old star just past its red-giant state and with an exposed core) for about two years. While analyzing the data, Charpinet noticed two tiny variations repeated in 5.76 and 8.23 hour intervals.

He asked other astronomers - including Kawaler - to analyze the original Kepler data and a subsequent set of data to see if they could also see the variations.

"We saw them in the same place and the same periodicity," Kawaler said. "So we knew they were real."

That led to the next question: "So what are they?"

Kawaler, working 26 years ago with the late Carl Hansen of the University of Colorado, had studied the fastest, and slowest, rates that stars could pulsate. Using that result, the team could conclude the variations seen by Kepler were too slow to be caused by the star itself. And so the astronomers started testing the idea that the variations were from two planets orbiting the star.

Astronomers believe the variations from the two planets - KOI 55.01 and KOI 55.02 - are caused by reflection of the star's light on the planets and by differences in thermal emissions from the hot day-sides and cooler night-sides of the planets.

The astronomers also report the two planets are 76 percent and 87 percent the size of Earth. That makes them among the smallest planets detected around a star other than our sun.

They further report the planets are very close to their host star, only .6 percent and .76 percent the distance between the sun and Earth. That means conditions on the planets are very harsh with temperatures up to 16,000 degrees Fahrenheit.

That's so close the host star's expansion as a red giant would have engulfed the planets, possibly stripping gaseous giants similar to Jupiter down to their dense cores. The planets also could have contributed to the host star's unusual loss of mass.

The research team said the discovery of the two planets raises many questions about their ability to survive such harsh conditions. It also raises questions about how planets can affect the evolution of their host stars.

Kawaler said NASA's Kepler Mission, launched in March 2009, is a tremendous tool for studying stars and planets. So much so, astronomers are working to extend the Kepler Mission another four years, from 2012 into 2016.

Kepler's primary job is to detect tiny variations in the brightness of the stars within its view to find Earth-like planets that might be able to support life.

The Kepler Asteroseismic Investigation is also using Kepler data to study different kinds of stars. The investigation is led by a four-member steering committee: Kawaler, Chair Ron Gilliland of the Space Telescope Science Institute based in Baltimore, Jorgen Christensen-Dalsgaard and Hans Kjeldsen, both of Aarhus University in Denmark.


Related Links
Iowa State University
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 DiggDigg RedditReddit GoogleGoogle

First Earth-sized planets found
Boston TX (SPX) Dec 21, 2011
Astronomers using NASA's Kepler mission have detected two Earth-sized planets orbiting a distant star. This discovery marks a milestone in the hunt for alien worlds, since it brings scientists one step closer to their ultimate goal of finding a twin Earth. "The goal of Kepler is to find Earth-sized planets in the habitable zone. Proving the existence of Earth-sized exoplanets is a major st ... read more

Peres promotes Israeli moon probe

Hundreds of NASA's moon rocks missing: audit

Schafer Corp Signs Licensing Agreement with MoonDust Technologies

Russia wants to focus on Moon if Mars mission fails

Meteorite Shock Waves Trigger Dust Avalanches on Mars

Opportunity at One of its Two Winter Spots

Scientists find microbes in lava tube living in conditions like those on Mars

MARSIS Completes Measurement Campaign Over Martian North Pole

Astrophysicist John Grunsfeld to Head NASA Science Directorate

A Brighter Future for Spaceflight

Goddard Scientists Selected as Participating Scientists in Mars Lab and Cassini Missions

Mankind faces long road in space exploration

Tiangong-1 orbiter starts planned cabin checks against toxic gas

China celebrates success of space docking mission

Two and a Half Men for Shenzhou

China honors its 'father' of space efforts

NASA 'Smart SPHERES' Tested on ISS

Russia sends multinational crew to ISS

As Soyuz Rolls ISS Crew Work On Science

ESA astronaut Andre Kuipers Ready For Launch To ISS

Next ESA Astronaut Ready For Launch As Soyuz Rolls Out

Acra Control Proven in Low Earth Orbit

Vega moves closer to its first liftoff

Arianespace Signs First launch contracts for Vega

NASA Discovers First Earth-Size Planets Beyond Our Solar System

Exo planets that survived red giant stage found

NASA Discovers First Earth-size Planets Beyond Our Solar System

First Earth-sized planets found

Need a new material? New tool can help

Belarus Strongman Vows Nation Will Build World's Best Spacecraft Ever

Canada hunts for rare earth metals as China cuts back

Split decision in Microsoft smartphone patent case

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