Featured Research

from universities, journals, and other organizations

'Dimer molecules' aid study of exoplanet pressure, hunt for life

Date:
March 4, 2014
Source:
University of Washington
Summary:
Astronomers have developed a new method of gauging the atmospheric pressure of exoplanets, or worlds beyond the solar system, by looking for a certain type of molecule. And if there is life out in space, scientists may one day use this same technique to detect its biosignature -- the telltale chemical signs of its presence -- in the atmosphere of an alien world.

An artist’s concept of an exoplanet, or planet outside the solar system.
Credit: NASA

Astronomers at the University of Washington have developed a new method of gauging the atmospheric pressure of exoplanets, or worlds beyond the solar system, by looking for a certain type of molecule.

And if there is life out in space, scientists may one day use this same technique to detect its biosignature -- the telltale chemical signs of its presence -- in the atmosphere of an alien world.

Understanding atmospheric pressure is key to knowing if conditions at the surface of a terrestrial, or rocky, exoplanet might allow liquid water, thus giving life a chance.

The method, devised by Amit Misra, a UW astronomy doctoral student, and co-authors, involves computer simulations of the chemistry of Earth's own atmosphere that isolate what are called "dimer molecules" -- pairs of molecules that tend to form at high pressures and densities in a planet's atmosphere. There are many types of dimer molecules but this research focused only on those of oxygen.

Misra and team ran simulations testing the spectrum of light in various wavelengths. Dimer molecules absorb light in a distinctive pattern, and the rate at which they form is sensitive to the pressure, or density, in the planet's atmosphere.

"So the idea is that if we were able to do this for another planet, we could look for this characteristic pattern of absorption from dimer molecules to identify them," Misra said. The presence of such molecules, he said, likely means the planet has at least one-quarter to one-third the pressure of Earth's atmosphere.

Powerful telescopes soon to come online, such as the James Webb Space Telescope, scheduled for launch in 2018, may enable astronomers to use this method on distant exoplanets. With such enhanced tools, Misra said, astronomers might detect dimer molecules in actual exoplanet atmospheres, leading to a clear understanding of the planet's atmosphere.

This research may also play a part in the greatest astronomical quest of all -- the ongoing search for life in the cosmos.

That's because the team realized along the way that oxygen dimer molecules are often more detectable in an atmosphere than other markers of oxygen. That's important from a biological standpoint, Misra said.

"It's tied to photosynthesis, and we have pretty good evidence that it's hard to get a lot of oxygen in an atmosphere unless you have algae or plants that are producing it at a regular rate.

"So if we find a good target planet, and you could detect these dimer molecules -- which might be possible within the next 10 to 15 years -- that would not only tell you something about pressure, but actually tell you that there's life on that planet."

Misra's UW co-author is Victoria Meadows, professor of astronomy; other co-authors are Mark Claire of Scotland's University of St. Andrews and Dave Crisp of NASA's Jet Propulsion Laboratory in Pasadena, Calif.

The team's paper was published in the February issue of the journal Astrobiology.

The research was performed through the UW-based Virtual Planetary Laboratory and funded by NASA (Grant NNH05ZDA001C), as well as a grant from Advancing Science in America, Seattle chapter.


Story Source:

The above story is based on materials provided by University of Washington. The original article was written by Peter Kelley. Note: Materials may be edited for content and length.


Journal Reference:

  1. Amit Misra, Victoria Meadows, Mark Claire, Dave Crisp. Using Dimers to Measure Biosignatures and Atmospheric Pressure for Terrestrial Exoplanets. Astrobiology, 2014; 14 (2): 67 DOI: 10.1089/ast.2013.0990

Cite This Page:

University of Washington. "'Dimer molecules' aid study of exoplanet pressure, hunt for life." ScienceDaily. ScienceDaily, 4 March 2014. <www.sciencedaily.com/releases/2014/03/140304154527.htm>.
University of Washington. (2014, March 4). 'Dimer molecules' aid study of exoplanet pressure, hunt for life. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2014/03/140304154527.htm
University of Washington. "'Dimer molecules' aid study of exoplanet pressure, hunt for life." ScienceDaily. www.sciencedaily.com/releases/2014/03/140304154527.htm (accessed July 25, 2014).

Share This




More Space & Time News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: ISS Cargo Ship Launches in Kazakhstan

Raw: ISS Cargo Ship Launches in Kazakhstan

AP (July 23, 2014) The Progress 56 cargo ship launched from the Baikonur Cosmodrome in Kazakhstan Wednesday. NASA says it will deliver cargo and crew supplies to the International Space Station. (July 23) Video provided by AP
Powered by NewsLook.com
Raw: Cargo Craft Undocks from Space Station

Raw: Cargo Craft Undocks from Space Station

AP (July 22, 2014) A Russian Soyuz cargo-carrying spacecraft undocked from the International Space Station on Monday. The craft is due to undergo about ten days of engineering tests before it burns up in the Earth's atmosphere. (July 22) Video provided by AP
Powered by NewsLook.com
NASA Ceremony Honors Moon Walker Neil Armstrong

NASA Ceremony Honors Moon Walker Neil Armstrong

AP (July 21, 2014) NASA honored one of its most famous astronauts Monday by renaming a historic building at the Kennedy Space Center in Florida. It now bears the name of Neil Armstrong, the first man to walk on the moon. (July 21) Video provided by AP
Powered by NewsLook.com
Neil Armstrong's Post-Apollo 11 Life

Neil Armstrong's Post-Apollo 11 Life

Newsy (July 19, 2014) Neil Armstrong gained international fame after becoming the first man to walk on the moon in 1969. But what was his life like after the historic trip? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins