Friday , September 25 2020
Home / zimbabwe / Exoplanet atmosphere models

Exoplanet atmosphere models


Exoplanet atmosphere models

An image of Pluto's sumptuous atmosphere, highlighted by the sun, as captured by New Horizons spacecraft. Astronomers who are planetary atmospheres to start studying other stars rely on & quot; HITRAN's molecular properties database to model their results. CfA scientists have recently updated HITRAN with the diagnostic properties of molecules that are expected to be important in exoplanets, including those that are thought to be biomarkers. Credit: NASA / JHUAPL / SwRI

All atoms and molecules emit distinct spectral lines across the spectrum, details are dependent on & # 39; internal structures; types (such as the vibrational and rotational properties of molecules) and how they are absorbed by their surroundings. Measurements from & brightness, relative intensity & shapes of & # 39; features can at least in principle reconstruct astronomers the most essential features of these environments, including species, temperatures, densities and motion. But to be successful, scientists need to quantitatively just know how to influence the temperature, density, etc. The excitement of each atom or molecule, and how to release each kind of light in response. A collision between oxygen and nitrogen molecules, for example, will affect an oxygen molecule other than its impingement with hydrogen.

CfA astronomers develop and maintain the HITRAN (High Resolution Transmission) database, a compilation of diagnostic spectroscopic parameters that is the global standard for calculating atmospheric molecular radiation from a microwave through the ultraviolet region of the spectrum. HITRAN has received a remarkable interest over the past few years with the discovery of thousands of exoplanets and the steadily improving technology to detect its atmosphere and measure its compositions. HITRAN is often used to model these exotic spheres. For example, molecular oxygen absorption stimulated by oxygen molecule collisions is thought to be an important biomarker on potentially inhabitable exoplanets, but the detection of this feature for absorption is not enough: it needs an interpretation.

CfA astrophysicists Tijs Karman, Iouli Gordon, Bob Kurucz, Larry Rothman, and Kang Sun lead a team of collaborators in updating HITRAN with many of & # 39; an essential absorption feature of & # 39; collision need molecules for modeling exoplanet atmospheres. Key molecular species include nitrogen, oxygen, methane, carbon dioxide, and hydrogen. The numerical parameters were retrieved from a wide range of recent laboratory and theoretical papers and recorded in & quot; HITRAN & quot; database to & # 39; they did not validate them. The updated compilation goes a long way towards addressing current needs, but the authors note that additional laboratory and theoretical work is needed to produce other effects, such as water, such as the isotopic variants of & # 39; e currently include recorded types.

Researchers discover how impinging oxygen molecules absorb light

More information:
Tijs Karman et al. Update from & # 39; section e HITRAN collision-inducing recording, Icarus (2019). DOI: 10.1016 / j.icarus.2019.02.034

Deliver by
Harvard-Smithsonian Astrophysics Center

Exoplanet Atmosphere Models (2019, July 23)
July 23, 2019 pick up

This document is subject to copyright. Except for all fair treatment for the purpose of private study or research, no
Part can be reproduced without written permission. The content is provided for information only.

Source link