Related papers: The Vegetation Red Edge Spectroscopic Feature as a…
Among the many recommendations of the Decadal Survey on Astronomy and Astrophysics 2020, we found that a priority area of research is to pave the pathways towards finding and characterizing habitable worlds. In this context, we aim to…
As we begin to discover rocky planets in the habitable zone of nearby stars with missions like TESS and CHEOPS, we will need quick advancements on instrumentation and observational techniques that will enable us to answer key science…
We report the visible reflection spectrum of the integrated Earth, illuminated as it would be seen as an spatially-unresolved extrasolar planet. The spectrum was derived from observation of lunar earthshine in the range 4800 to 9200…
One of the big challenges in exoplanet science is to determine the atmospheric makeup of extrasolar planets, and to find biosignatures that hint at the existence of biochemical processes on another world. The biomarkers we are trying to…
We investigate the spectra of Earth-like planets but with different axial rotation periods. Using the general circulation model of the atmosphere and considering the atmospheric circulation lasting for two years, we calculated the radiation…
We report spectroscopic observations of the earthshine reflected from the Moon. By applying our photometry methodology to spectroscopy, we were able to precisely determine the Earth's reflectance, and its variation as a function of…
We review some of the characteristics of irradiated extrasolar giant planets (EGPs), in anticipation of their direct detection from the ground and from space. Spectral measurements are the key to unlocking their structural and atmospheric…
Magnetic fields play a crucial role in planetary evolution and habitability. While the intrinsic magnetic fields of solar system planets are relatively well understood, the magnetic properties of exoplanets remain largely unconstrained,…
We review the field of exoplanetary biosignatures with a main focus upon atmospheric gas-phase species. Due to the paucity of data in Earth-like planetary atmospheres a common approach is to extrapolate knowledge from the Solar System and…
Temperature-dependent biological productivity controls silicate weathering and thereby extends the potential habitable timespan of Earth. Models and theoretical considerations indicate that the runaway greenhouse on Earth-like exoplanets is…
The search for biosignatures necessitates developing our understanding of life under different conditions. If life can influence the climate evolution of its planet then understanding the behaviour of life-climate feedbacks under extreme…
This article reviews the emerging field of exo-geoscience, focusing on the geological and geophysical processes thought to influence the evolution and (eu)habitability of rocky exoplanets. We examine the possible roles of planetary…
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 consist of predominantly unicellular microorganisms due…
We present a comprehensive set of spectropolarimetric observations of Earthshine as obtained by FORS2 at the VLT for phase angles from 50degree to 135degree (Sun-Earth-Moon angle), covering a spectral range from 430nm to 920nm. The degree…
The search for extraterrestrial life hinges on identifying biosignatures, often focusing on gaseous metabolic byproducts as indicators. However, most such biosignatures require assuming specific metabolic processes. It is widely recognized…
Exoplanet hunting efforts have revealed the prevalence of exotic worlds with diverse properties, including Earth-sized bodies, which has fueled our endeavor to search for life beyond the Solar System. Accumulating experiences in…
Vegetation can modify the planetary surface albedo via the Charney mechanism, as plants are usually darker than the bare surface of the continents. We updated ESTM (Earth-like Surface Temperature Model) to incorporate the presence,…
Geological activity is thought to be important for the origin of life and for maintaining planetary habitability. We show that transient sulfate aerosols could be a signature of exoplanet volcanism, and therefore a geologically active…
It is expected that the next generation of high-contrast imaging instruments will deliver the first unresolved image of an extrasolar planet. The emitted thermal infrared light from the planet should show no phase effect assuming the planet…
How can scientists conclude with high confidence that an exoplanet hosts life? As telescopes come on line over the next 20 years that can directly observe photons from terrestrial exoplanets, this question will dictate the activities of…