A Review of Exoplanetary Biosignatures

@article{Grenfell2017ARO,
  title={A Review of Exoplanetary Biosignatures},
  author={John Lee Grenfell},
  journal={arXiv: Earth and Planetary Astrophysics},
  year={2017}
}
  • J. Grenfell
  • Published 11 October 2017
  • Geology, Physics
  • arXiv: Earth and Planetary Astrophysics
Exoplanetary Biosignatures for Astrobiology
  • J. Grenfell
  • Geology, Physics
    Biosignatures for Astrobiology
  • 2018
Since life evolved on our planet there have been subtle interplays between biology and Earth System Components (atmosphere-lithosphere-ocean-interior). Life, for example, can impact weathering rates
Super-Earths, M Dwarfs, and Photosynthetic Organisms: Habitability in the Lab
TLDR
These findings highlight the importance of simulating both the visible and FR light components of an M dwarf spectrum to correctly evaluate the photosynthetic performances of oxygenic organisms exposed under such an exotic light condition.
Assessment of Isoprene as a Possible Biosignature Gas in Exoplanets with Anoxic Atmospheres
Detecting biosignature gases on exoplanet atmosphere with near-future space telescopes is one of the most promising methods of detecting life beyond Earth. However, only a handful of biosignature g...
Differentiating modern and prebiotic Earth scenarios for TRAPPIST-1e: high-resolution transmission spectra and predictions for JWST
The TRAPPIST-1 system is a priority target for terrestrial exoplanet characterization. TRAPPIST-1e, residing in the habitable zone, will be observed during the JWST GTO Program. Here, we assess the
Impact of space weather on climate and habitability of terrestrial-type exoplanets
Abstract The search for life in the Universe is a fundamental problem of astrobiology and modern science. The current progress in the detection of terrestrial-type exoplanets has opened a new avenue
Detectability of Chlorofluorocarbons in the Atmospheres of Habitable M-dwarf Planets
The presence of chlorofluorocarbons (CFCs) in Earth’s atmosphere is a direct result of technology. Ozone-depleting CFCs have been banned by most countries, but some CFCs have persisted in elevated
Biosignatures Search in Habitable Planets
The search for life has had a new enthusiastic restart in the last two decades thanks to the large number of new worlds discovered. The about 4100 exoplanets found so far, show a large diversity of
Quantifying the information impact of future searches for exoplanetary biosignatures
TLDR
It is shown that even a single detection of biosignatures in the vicinity of the authors' stellar system, in a survey of similar size to what will be obtainable in the next 2 decades, would affect significantly their prior belief on the frequency of life in the universe.
Searching for Atmospheric Bioindicators in Planets around the Two Nearby Stars, Proxima Centauri and Epsilon Eridani-Test Cases for Retrieval of Atmospheric Gases with Infrared Spectroscopy.
TLDR
Thermal infrared spectroscopy is tested to retrieve assumed atmospheric compositions for different types of planets orbiting Proxima Centauri and Epsilon Eridani to identify the planet's nature and have an idea of surface conditions, which are necessary when testing for the presence of life.
Subsurface exolife
Abstract We study the prospects for life on planets with subsurface oceans, and find that a wide range of planets can exist in diverse habitats with ice envelopes of moderate thickness. We quantify
...
1
2
3
4
...

References

SHOWING 1-10 OF 174 REFERENCES
Potential biosignatures in super-Earth atmospheres II. Photochemical responses.
TLDR
An important result of the analysis is a shift in the ozone photochemistry from mainly Chapman production to smog-dominated ozone production for planets in the habitable zone of cooler (M5-M7)-class dwarf stars, associated with a lower energy flux in the UVB wavelength range from the central star.
Toward a List of Molecules as Potential Biosignature Gases for the Search for Life on Exoplanets and Applications to Terrestrial Biochemistry.
TLDR
A new approach to the subject of biosignature gases is presented by systematically constructing lists of volatile molecules in different categories, and it is shown that about one-fourth of CNOPSH molecules are known to be produced by life on Earth.
N 2 O as a Biomarker, from the Earth and Solar System to Exoplanets
Since its discovery in the earth’s atmosphere in 1938, N2O sources and sinks have been a puzzle. N2O has now been identified as produced by anaerobic bacteria’s in soils which are sufficiently acid.
A BIOMASS-BASED MODEL TO ESTIMATE THE PLAUSIBILITY OF EXOPLANET BIOSIGNATURE GASES
Biosignature gas detection is one of the ultimate future goals for exoplanet atmosphere studies. We have created a framework for linking biosignature gas detectability to biomass estimates, including
Swansong biospheres II: the final signs of life on terrestrial planets near the end of their habitable lifetimes
Abstract The biosignatures of life on Earth do not remain static, but change considerably over the planet's habitable lifetime. Earth's future biosphere, much like that of the early Earth, will
Detecting industrial pollution in the atmospheres of earth-like exoplanets
Detecting biosignatures, such as molecular oxygen in combination with a reducing gas, in the atmospheres of transiting exoplanets has been a major focus in the search for alien life. We point out
Biosignatures of early earths.
TLDR
Inferred characteristics of Earth's earliest biosphere and studies of modern microbial ecosystems that share some of those characteristics suggest that organosulfur compounds, particularly methanethiol (CH(3)SH, the sulfur analog of methanol), may have been biogenic products on early Earth.
Some inconvenient truths about biosignatures involving two chemical species on Earth-like exoplanets
TLDR
A previously unidentified kind of false positive that can mimic a disequilibrium or any other biosignature that involves two chemical species is presented and a firm limit on the maximum spectral resolution that can be obtained for both directly imaged and transiting planets is derived.
...
1
2
3
4
5
...