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 is first author of the paper was published in the February issue of the journal Astrobiology.
The researchers 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 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.
For more information, contact Misra at 440-554-6514 or email@example.com
Peter Kelley | EurekAlert!
Knots in chaotic waves
29.07.2016 | University of Bristol
International team of scientists unveils fundamental properties of spin Seebeck effect
29.07.2016 | Johannes Gutenberg-Universität Mainz
Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.
To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...
A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology
On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...
Researchers at the U.S. Department of Energy's (DOE) Ames Laboratory have discovered an unusual property of purple bronze that may point to new ways to achieve high temperature superconductivity.
While studying purple bronze, a molybdenum oxide, researchers discovered an unconventional charge density wave on its surface.
Munich Physicists have developed a novel electron microscope that can visualize electromagnetic fields oscillating at frequencies of billions of cycles per second.
Temporally varying electromagnetic fields are the driving force behind the whole of electronics. Their polarities can change at mind-bogglingly fast rates, and...
Breakup of continents with two speed: Continents initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. The final speed can be up to 20 times faster than in the first, slow extension phase.phases
Present-day continents were shaped hundreds of millions of years ago as the supercontinent Pangaea broke apart. Derived from Pangaea’s main fragments Gondwana...
29.07.2016 | Event News
15.07.2016 | Event News
15.07.2016 | Event News
29.07.2016 | Power and Electrical Engineering
29.07.2016 | Life Sciences
29.07.2016 | Event News