Related papers: Observational Constraints on the Great Filter
This is a personal review of various issues related to massive photometric and astrometric searches. A complete inventory of variable stars down to almost any magnitude limit will improve our understanding of the stellar evolution and the…
The search for signatures of life beyond Earth has been a major goal of space research and astrobiology for decades. The combination of expanded knowledge on Solar System bodies from past missions and advancements in in-situ detection…
The characterization of extrasolar earth-like atmospheres for biosignatures remains one of the most compelling and elusive challenges in astronomy. Coronagraphy, nulling interferometry and free-flying occulters have been advanced as…
In this paper we address the cosmic frequency of technological species. Recent advances in exoplanet studies provide strong constraints on all astrophysical terms in the Drake Equation. Using these and modifying the form and intent of the…
"From Cosmic Birth to Living Earths" advocates a 12-meter optical/near-IR space telescope for launch ~2035. The goal that sets this large size is the detection of biosignatures from Earth-like planets in their habitable zones around…
Gravitational microlensing finds planets through their gravitational influence on the light coming from a more distant background star. The presence of the planet is then inferred from the tell-tale brightness variations of the background…
We propose and evaluate the feasibility of a new strategy to search for planets via microlensing observations. This new strategy is designed to detect planets in "wide" orbits, i.e., with orbital separation, a, greater than ~1.5 R_E.…
The goal of the Search for Extraterrestrial Intelligence (SETI) is to quantify the prevalence of technological life beyond Earth via their "technosignatures". One theorized technosignature is narrowband Doppler drifting radio signals. The…
Methane has been proposed as an exoplanet biosignature. Imminent observations with the James Webb Space Telescope may enable methane detections on potentially habitable exoplanets, so it is essential to assess in what planetary contexts…
Significant advances in the discovery and characterization of the planetary systems of nearby stars can be accomplished with a moderate aperture high performance coronagraphic space mission that could be started in the next decade. Its…
Dozens of habitable zone, approximately earth-sized exoplanets are known today. An emerging frontier of exoplanet studies is identifying which of these habitable zone, small planets are actually habitable (have all necessary conditions for…
This study examines the hypothesis that the rapid development of Artificial Intelligence (AI), culminating in the emergence of Artificial Superintelligence (ASI), could act as a "Great Filter" that is responsible for the scarcity of…
The search for extrasolar Earth-like planets is underway. Over 100 extrasolar giant planets are known to orbit nearby sun-like stars, including several in multiple-planet systems. These planetary systems are stepping stones for the search…
The search for atmospheric biosignatures in Earth-like exoplanets is one of the most pressing challenges in observational astrobiology. Detecting biogenic gases in terrestrial planets requires high-resolution observations and long…
This paper puts forward a possible new indicator for the presence of moderately advanced civilizations on transiting exoplanets. The idea is to examine the region of space around a planet where potential geostationary or geosynchronous…
In this work, we assess the potential detectability of solar panels made of silicon on an Earth-like exoplanet as a potential technosignature. Silicon-based photovoltaic cells have high reflectance in the UV-VIS and in the near-IR, within…
Our first targets in the search for signs of life are orbiting nearby M stars, such as the planets in the Proxima Centauri, Ross-128, LHS-1140, and TRAPPIST-1 systems. Future ground-based discoveries, and those from the TESS mission, will…
The search for life in the universe mainly uses modern Earth as a template. However, we know that Earth's atmospheric composition changed significantly through its geological evolution. Recent discoveries show that transiting, potentially…
Oxygen is a promising exoplanet biosignature due to the evolutionary advantage conferred by harnessing starlight for photosynthesis, and the apparent low likelihood of maintaining oxygen-rich atmospheres without life. Hypothetical scenarios…
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…