Related papers: Atmospheric Seasonality as an Exoplanet Biosignatu…
At the dawn of the first discovery of exoplanets orbiting sun-like stars in the mid-1990s, few believed that observations of exoplanet atmospheres would ever be possible. After the 2002 Hubble Space Telescope detection of a transiting…
In the JWST, Extremely Large Telescopes, and LUVOIR era, we expect to characterize a number of potentially habitable Earth-like exoplanets. However, the characterization of these worlds depends crucially on the accuracy of theoretical…
Context. Homochirality is a generic and unique property of life on Earth and is considered a universal and agnostic biosignature. Homochirality induces fractional circular polarization in the incident light that it reflects. Because this…
We have developed a characterization of the geological evolution of the Earths atmosphere and surface in order to model the observable spectra of an Earth-like planet through its geological history. These calculations are designed to guide…
Exoplanet atmosphere characterization has seen revolutionary advances over the last few years, providing us with unique insights into atmospheric chemistry, dynamics and planet formation mechanisms. However, true solar system analog planets…
The discovery of planets orbiting stars other than the Sun has accelerated over the past decade, and this trend will continue as new space- and ground-based observatories employ next-generation instrumentation to search the skies for…
The study of exoplanet atmospheres showed large diversity compared to the planets in our solar system. Especially Jupiter type exoplanets orbiting their host star in close orbits, the so-called hot and ultra-hot Jupiters, have been studied…
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…
This tutorial is an introduction to techniques used to characterize the atmospheres of transiting exoplanets. We intend it to be a useful guide for the undergraduate, graduate student, or postdoctoral scholar who wants to begin research in…
Research for possible biosignature gases on habitable exoplanet atmosphere is accelerating. We add isoprene, C5H8, to the roster of biosignature gases. We found that formation of isoprene geochemical formation is highly thermodynamically…
The goals of the astrobiology community are focussed on developing a framework for the detection of biosignatures, or evidence thereof, on objects inside and outside of our solar system. A fundamental aspect of understanding the limits of…
Our present-day atmosphere is often used as an analog for potentially habitable exoplanets, but Earth's atmosphere has changed dramatically throughout its 4.5 billion year history. For example, molecular oxygen is abundant in the atmosphere…
The atmospheric composition of transiting exoplanets can be characterized during transit by spectroscopy. For the transit of an Earth twin, models predict that biogenic $O_2$ and $O_3$ should be detectable, as well as water vapour, a…
Determining the habitability and interpreting future atmospheric observations of exoplanets requires understanding the atmospheric dynamics and chemistry from a 3-D perspective. Previous studies have shown significant spatial variability in…
In a famous paper, Sagan et al.(1993) analyzed a spectrum of the Earth taken by the Galileo probe, searching for signatures of life. They concluded that the large amount of O2 and the simultaneous presence of CH4 traces are strongly…
Earth-like, potentially habitable exoplanets are prime targets in the search for extraterrestrial life. Information about their atmosphere and surface can be derived by analyzing light of the parent star reflected by the planet. We…
Characterizing temperate exoplanet atmospheres remains challenging due to their small size and low temperatures. Recent JWST observations provide valuable data, but their interpretation has led to diverging conclusions. Complementary…
Before about 500 million years ago, most probably our planet experienced temporary snowball conditions, with continental and sea ices covering a large fraction of its surface. This points to a potential bistability of Earth's climate, that…
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…
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…