Results 91 to 100 of about 7,177 (211)

Evaluating the biosignature potential of ammonium in Proterozoic red beds and implications for the search for life on Mars

Earth and Planetary Physics
Over the past two decades, it has become increasingly apparent that early Mars may once have been warmer, wetter and more habitable for microbial life than it is today, which has spurred discussions about potential biosignatures that may be preserved in ...
Eva E. Stüeken, Philip Fralick, Stephen Hillier, Anthony R. Prave   +3 more
doaj   +1 more source

Spectral signatures of photosynthesis II: coevolution with other stars and the atmosphere on extrasolar worlds

, 2007
As photosynthesis on Earth produces the primary signatures of life that can be detected astronomically at the global scale, a strong focus of the search for extrasolar life will be photosynthesis, particularly photosynthesis that has evolved with a ...
Antígona Segura, David Crisp, Giovanna Tinetti, Govindjee, , Janet Siefert, Leger A., Leger A., Martin Cohen, Nancy Y. Kiang, Robert E. Blankenship, Tucker C.J., Victoria S. Meadows, Wang A.   +12 more
core   +2 more sources

Identifying Planetary Biosignature Impostors: Spectral Features of CO and O4 Resulting from Abiotic O2/O3 Production

, 2016
O2 and O3 have been long considered the most robust individual biosignature gases in a planetary atmosphere, yet multiple mechanisms that may produce them in the absence of life have been described.
Arney, Giada N., Barnes, Rory, Deming, Drake, Domagal-Goldman, Shawn D., Harman, Chester E., Luger, Rodrigo, Meadows, Victoria S., Misra, Amit, Schwieterman, Edward W.   +8 more
core   +1 more source

Metabolic Processes Preserved as Biosignatures in Iron-Oxidizing Microorganisms: Implications for Biosignature Detection on Mars [PDF]

Iron-oxidizing bacteria occupy a distinct environmental niche. These chemolithoautotrophic organisms require very little oxygen (when neutrophilic) or outcompete oxygen for access to Fe(II) (when acidophilic).
Emerson, David, Floyd, Melissa A. Merrill, Grubisic, Andrej, Williams, Amy J.   +3 more
core   +1 more source

Comparative Biosignatures

The discovery of inhabited exoplanets hinges on identifying biosignature gases. JWST is revealing potential biosignatures in exoplanet atmospheres, though their presence is yet to provide strong evidence for life. The central challenge is attribution: how to confidently identify biogenic sources while ruling out, or deeming unlikely, abiotic ...
Constantinou, Tereza, Shorttle, Oliver, Cranmer, Miles, Rimmer, Paul B.   +3 more
openaire   +2 more sources

Characterizing the Habitable Zones of Exoplanetary Systems with a Large Ultraviolet/Visible/Near-IR Space Observatory [PDF]

, 2015
Understanding the surface and atmospheric conditions of Earth-size, rocky planets in the habitable zones (HZs) of low-mass stars is currently one of the greatest astronomical endeavors.
Ayres, Thomas, Barman, Travis, Brown, Alexander, Davenport, James, Desert, Jean-Michel, Domagal-Goldman, Shawn, Fleming, Brian, Fontenla, Juan, Fossati, Luca, France, Kevin, Froning, Cynthia, Hallinan, Gregg, Hawley, Suzanne, Hu, Renyu, Kaltenegger, Lisa, Kasting, James, Kowlaski, Adam, Linsky, Jeffrey, Loyd, Parke, Mauas, Pablo, Miguel, Yamila, Osten, Rachel, Redfield, Seth, Roberge, Aki, Rugheimer, Sarah, Schneider, Christian, Segura, Antigona, Shkolnik, Evgenya, Stocke, John, Tian, Feng, Tumlinson, Jason, Vieytes, Mariela, Walkowicz, Lucianne, Wood, Brian, Youngblood, Allison   +34 more
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Novel Phospholipid Signature of Depressive Symptoms in Patients With Coronary Artery Disease

Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease, 2018
BackgroundDepression in patients with coronary artery disease (CAD) is associated with increased cardiovascular morbidity. Given the proinflammatory actions of phospholipids, aberrant phospholipid metabolism may be an etiological mechanism linking CAD ...
Parco Chan, Ivonne Suridjan, Dana Mohammad, Nathan Herrmann, Graham Mazereeuw, Lyn M. Hillyer, David W. L. Ma, Paul I. Oh, Krista L. Lanctôt   +8 more
doaj   +1 more source

Habitability and biosignatures

Preprint of a chapter for the 'Encyclopedia of Astrophysics' (Editor-in-Chief Ilya Mandel, Section Editor Dimitri Veras) to be published by Elsevier as a Reference ...
openaire   +2 more sources

Biosignature False Positives [PDF]

, 2018
In our search for life - whether within the earliest part of Earth's geologic record, on planets within our solar system such Mars, or especially for extrasolar planets - we must infer the presence of life from its impact on the local or global environment. These "biosignatures," often identified from the known influence of terrestrial organisms on the
Chester E. Harman, Shawn Domagal-Goldman
openaire   +1 more source

Life-Detection Technologies for the Next Two Decades

, 2018
Since its inception six decades ago, astrobiology has diversified immensely to encompass several scientific questions including the origin and evolution of Terran life, the organic chemical composition of extraterrestrial objects, and the concept of ...
Bodas, Dhananjay, Carr, Christopher, Chen, Huan, Cleaves II, H. James, Fujii, Yuka, Furukawa, Yoshihiro, Genda, Hidenori, Gillams, Richard J., Giri, Chaitanya, Hamano, Keiko, Jia, Tony Z., Kameda, Shingo, Krishnamurthy, Ramanarayanan, Meinert, Cornelia, Meringer, Markus, Paknikar, Kishore, Rajamani, Sudha, Shivaji, Sisinthy, Steele, Andrew, Taniguchi, Masateru, Usui, Tomohiro, Yabuta, Hikaru, Yamagishi, Akihiko   +22 more
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