Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Earth-sized planets in habitable zones are more common than previously thought

13.03.2013
The number of potentially habitable planets is greater than previously thought, according to a new analysis by a Penn State researcher, and some of those planets are likely lurking around nearby stars.

"We now estimate that if we were to look at 10 of the nearest small stars we would find about four potentially habitable planets, give or take," said Ravi Kopparapu, a post-doctoral researcher in geosciences. "That is a conservative estimate," he added. "There could be more."


This shows starlight on planet relative to sunlight on the Earth.

Credit: Chester Harman

Kopparapu detailed his findings in a paper accepted for publication in Astrophysical Journal Letters. In it, he recalculated the commonness of Earth-sized planets in the habitable zones of low-mass stars, also known as cool stars or M-dwarfs.

Scientists focus on M-dwarfs for several reasons, he explained. The orbit of planets around M-dwarfs is very short, which allows scientists to gather data on a greater number of orbits in a shorter period of time than can be gathered on Sun-like stars, which have larger habitable zones. M-dwarfs are also more common than stars like the Earth's Sun, which means more of them can be observed.

According to his findings, "The average distance to the nearest potentially habitable planet is about seven light years. That is about half the distance of previous estimates," Kopparapu said. "There are about eight cool stars within 10 light-years, so conservatively, we should expect to find about three Earth-size planets in the habitable zones."

The work follows up on a recent study by researchers at the Harvard-Smithsonian Center for Astrophysics which analyzed 3,987 M-dwarf stars to calculate the number of Earth-sized planet candidates in cool stars' habitable zones—a region around a star where rocky planets are capable of sustaining liquid water and therefore life. That study used habitable zone limits calculated in 1993 by Jim Kasting, now an Evan Pugh Professor in Penn State's Department of Geosciences. Kopparapu noticed that its findings, based on data from NASA's Kepler satellite, didn't reflect the most recent estimates for determining whether planets fall within a habitable zone.

These newer estimates are based on an updated model developed by Kopparapu and collaborators, using information on water and carbon dioxide absorption that was not available in 1993. Kopparapu applied those findings to the Harvard team's study, using the same calculation method, and found that there are additional planets in the newly determined habitable zones.

"I used our new habitable zone calculations and found that there are nearly three times as many Earth-sized planets in the habitable zones around these low mass stars as in previous estimates," Kopparapu said. "This means Earth-sized planets are more common than we thought, and that is a good sign for detecting extraterrestrial life."

Anne Danahay | EurekAlert!
Further information:
http://www.psu.edu

More articles from Physics and Astronomy:

nachricht Tiny lasers from a gallery of whispers
20.09.2017 | American Institute of Physics

nachricht New quantum phenomena in graphene superlattices
19.09.2017 | Graphene Flagship

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Molecular Force Sensors

20.09.2017 | Life Sciences

Producing electricity during flight

20.09.2017 | Power and Electrical Engineering

Tiny lasers from a gallery of whispers

20.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>