Researchers get clearer view of Earth's atmosphere --- from the laboratory

June 23, 2005

COLUMBUS , Ohio - For scientists who want to discern the complex chemistry at work in Earth's atmosphere, detecting a particular gas molecule can be as hard as finding a proverbial needle in a haystack.

Frank De Lucia, professor of physics at Ohio State University , and his colleagues recently used their FAST Scan Submillimeter Spectroscopy Technique (FASSST) to make the job easier.

The technique offers a way for scientists to examine the spectrum of light given off by a molecule. Each molecule has its own one-of-a-kind spectral pattern, like lines in a bar code. FASSST takes a snapshot of a wide range of spectral wavelengths, so scientists can easily recognize the pattern of the molecule they are looking for. Experiments that have traditionally taken weeks or months can be completed in a few seconds.

At the 60th International Symposium on Molecular Spectroscopy, hosted by Ohio State University , De Lucia and doctoral student Andrey Meshkov reported that the FASSST technique can be used to help scientists remove the signals from molecules that interfere with studies of gas systems such as Earth's atmosphere.

De Lucia used the example of a problem common to his collaborators at NASA: satellite measurements of chemicals involved in the creation or destruction of ozone.

"Say you're trying to look though the atmosphere to see small amounts of hydrogen peroxide. You have to understand how the signal from the hydrogen peroxide changes as it travels through the atmosphere to a satellite," he said. "The path that the signal follows can be thousands of kilometers long, so you have to be able to subtract out the part of the atmosphere that you don't care about to get at the really small effects that you do care about."

The background signal from other molecules that scientists are not interested in -- frequently molecules of water, oxygen, or nitrogen -- is called the continuum. FASSST lets scientists get a handle on the continuum signal by essentially freezing an atmosphere in time so scientists can remove the parts they don't want.

In their latest results reported at the symposium, De Lucia and Meshkov used FASSST to simultaneously measure the contributions of water, oxygen, and nitrogen to the continuum in an experimental gas mixture they created in the laboratory.

De Lucia said his colleagues at NASA and elsewhere can use experimental data from FASSST to better interpret satellite data and reduce error in their measurements.

The same technique aids detection of chemicals in the lab in general. Several of the presentations at the symposium are based on FASSST analyses of chemicals important to research in astronomy and biology.
-end-
Written by Pam Frost Gorder, (614) 292-9475; Gorder.1@osu.edu

Ohio State University

Related Atmosphere Articles from Brightsurf:

ALMA shows volcanic impact on Io's atmosphere
New radio images from ALMA show for the first time the direct effect of volcanic activity on the atmosphere of Jupiter's moon Io.

New study detects ringing of the global atmosphere
A ringing bell vibrates simultaneously at a low-pitched fundamental tone and at many higher-pitched overtones, producing a pleasant musical sound. A recent study, just published in the Journal of the Atmospheric Sciences by scientists at Kyoto University and the University of Hawai'i at Mānoa, shows that the Earth's entire atmosphere vibrates in an analogous manner, in a striking confirmation of theories developed by physicists over the last two centuries.

Estuaries are warming at twice the rate of oceans and atmosphere
A 12-year study of 166 estuaries in south-east Australia shows that the waters of lakes, creeks, rivers and lagoons increased 2.16 degrees in temperature and increased acidity.

What makes Saturn's atmosphere so hot
New analysis of data from NASA's Cassini spacecraft found that electric currents, triggered by interactions between solar winds and charged particles from Saturn's moons, spark the auroras and heat the planet's upper atmosphere.

Galactic cosmic rays affect Titan's atmosphere
Planetary scientists using the Atacama Large Millimeter/submillimeter Array (ALMA) revealed the secrets of the atmosphere of Titan, the largest moon of Saturn.

Physics: An ultrafast glimpse of the photochemistry of the atmosphere
Researchers at Ludwig-Maximilians-Universitaet (LMU) in Munich have explored the initial consequences of the interaction of light with molecules on the surface of nanoscopic aerosols.

Using lasers to visualize molecular mysteries in our atmosphere
Molecular interactions between gases and liquids underpin much of our lives, but difficulties in measuring gas-liquid collisions have so far prevented the fundamental exploration of these processes.

The atmosphere of a new ultra hot Jupiter is analyzed
The combination of observations made with the CARMENES spectrograph on the 3.5m telescope at Calar Alto Observatory (Almería), and the HARPS-N spectrograph on the National Galileo Telescope (TNG) at the Roque de los Muchachos Observatory (Garafía, La Palma) has enabled a team from the Instituto de Astrofísica de Canarias (IAC) and from the University of La Laguna (ULL) to reveal new details about this extrasolar planet, which has a surface temperature of around 2000 K.

An exoplanet loses its atmosphere in the form of a tail
A new study, led by scientists from the Instituto de Astrofísica de Canarias (IAC), reveals that the giant exoplanet WASP-69b carries a comet-like tail made up of helium particles escaping from its gravitational field propelled by the ultraviolet radiation of its star.

Iron and titanium in the atmosphere of an exoplanet
Exoplanets can orbit close to their host star. When the host star is much hotter than our sun, then the exoplanet becomes as hot as a star.

Read More: Atmosphere News and Atmosphere Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.