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 28, 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 28, 2014).

Share This




More Space & Time News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Newsy (July 27, 2014) The satellite is back under ground control after a tense few days, but with a gecko sex experiment on board, the media just couldn't help themselves. Video provided by Newsy
Powered by NewsLook.com
This Week @ NASA, July 25, 2014

This Week @ NASA, July 25, 2014

NASA (July 25, 2014) Apollo 11 celebration, Next Giant Leap anticipation, ISS astronauts appear in the House and more... Video provided by NASA
Powered by NewsLook.com
Space to Ground: Coming and Going

Space to Ground: Coming and Going

NASA (July 25, 2014) One station cargo ship leaves, another arrives, aquatic research and commercial spinoffs. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com
How A Solar Flare Could Have Wrecked Earth's Electronics

How A Solar Flare Could Have Wrecked Earth's Electronics

Newsy (July 25, 2014) Researchers say if Earth had been a week earlier in its orbit around the sun, it would have taken a direct hit from a 2012 coronal mass ejection. 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