Bibcode
García Munõz, A.; Pallé, E.; Sanromá, E.
Bibliographical reference
The Astrophysical Journal, Volume 766, Issue 2, article id. 133, 8 pp. (2013).
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4
2013
Journal
Citations
17
Refereed citations
16
Description
Understanding the spectral and photometric variability of the Earth and
the rest of the solar system planets has become of utmost importance for
the future characterization of rocky exoplanets. As this is not only
interesting at present times but also along the planetary evolution, we
studied the effect that the evolution of microbial mats and plants over
land has had on the way our planet looks from afar. As life evolved,
continental surfaces changed gradually and non-uniformly from deserts
through microbial mats to land plants, modifying the reflective
properties of the ground and most likely the distribution of moisture
and cloudiness. Here, we used a radiative transfer model of the Earth,
together with geological paleo-records of the continental distribution
and a reconstructed cloud distribution, to simulate the visible and
near-IR radiation reflected by our planet as a function of Earth's
rotation. We found that the evolution from deserts to microbial mats and
to land plants produces detectable changes in the globally averaged
Earth's reflectance. The variability of each surface type is located in
different bands and can induce reflectance changes of up to 40% in
period of hours. We conclude that by using photometric observations of
an Earth-like planet at different photometric bands it would be possible
to discriminate between different surface types. While recent literature
proposes the red-edge feature of vegetation near 0.7 μm as a
signature for land plants, observations in near-IR bands can be equally
or even better suited for this purpose.
Related projects
Exoplanets and Astrobiology
The search for life in the universe has been driven by recent discoveries of planets around other stars (known as exoplanets), becoming one of the most active fields in modern astrophysics. The growing number of new exoplanets discovered in recent years and the recent advance on the study of their atmospheres are not only providing new valuable
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