Related papers: In Outer Space without a Space Suit?
The conventional observables to identify a habitable or inhabited environment in exoplanets, such as an ocean glint or abundant atmospheric O$_2$, will be challenging to detect with present or upcoming observatories. Here we suggest a new…
Here we advocate an observational strategy to help prioritize exoplanet observations. It starts with more easily obtained observational data, and ranks exoplanets for more difficult follow-up observations based on the likelihood of avoiding…
Mars exploration motivates the search for extraterrestrial life, the development of space technologies, and the design of human missions and habitations. Here we seek new insights and pose unresolved questions relating to the natural…
Extraterrestrial technology may exist in the Solar System without our knowledge. This is because the vastness of space, combined with our limited searches to date, implies that any remote unpiloted exploratory probes of extraterrestrial…
The term Biosphere Substrate is introduced for celestial bodies, like terrestrial planets or big gas giant moons, suitable to sustain full-scale open biosphere after Terraforming. The purpose of the work is to examine the range of…
The question of the nature of space around us has occupied thinkers since the dawn of humanity, with scientists and philosophers today implicitly assuming that space is something that exists objectively. Here we show that this does not have…
Some low-density exoplanets are thought to be water-rich worlds that formed beyond the snow line of their protoplanetary disc, possibly accreting coequal portions of rock and water. However, the compositions of bodies within the Solar…
As the only known habitable (and inhabited) planet in the universe, Earth informs our search for life elsewhere. Future telescopes like the Habitable Worlds Observatory (HWO) will soon look for life on rocky worlds around Sun-like stars, so…
This article deals with the most recent developments in the field of exoplanetary science connecting the interior of the planets with their habitability. In this issue, I have specified the importance of interior dynamics and briefly…
Bodies that lack a significant atmosphere and internal magnetic fields, such as the Moon and asteroids, can to a first approximation be considered passive absorbers of the solar wind. The solar wind ions and electrons directly impact the…
Traditional definitions of the habitable zone assume that habitable planets contain a carbonate-silicate cycle that regulates CO2 between the atmosphere, surface, and the interior. Such theories have been used to cast doubt on the…
The upper atmospheres of the planets and their satellites are more directly exposed to sunlight and solar wind particles than the surface or the deeper atmospheric layers. At the altitudes where the associated energy is deposited, the…
It is widely assumed that human exploration beyond Earth's orbit will require vehicles capable of providing long-duration habitats that simulate an Earthlike environment: consistent artificial gravity, breathable atmosphere, and sufficient…
Detection of life on other planets requires identification of biosignatures, i.e., observable planetary properties that robustly indicate the presence of a biosphere. One of the most widely accepted biosignatures for an Earth-like planet is…
Life has had a dramatic impact on the composition of Earth's atmosphere over time, which suggests that statistical studies of other inhabited planets' atmospheres could reveal how they co-evolve with life. While many evolutionary pathways…
One of the primary surprises of exoplanet detections has been the discovery of compact planetary systems, whereby numerous planets reside within ~0.5 AU of the host star. Many of these kinds of systems have been discovered in recent years,…
In this work we aim to determine the atmospheric survivability of the TRAPPIST-1 planets by modelling the response of the upper atmosphere to incoming stellar high-energy radiation. Through this case study, we also aim to learn more about…
Rogue planets have been ejected from their planetary system. We investigate the possibility that a rogue planet could maintain a liquid ocean under layers of thermally-insulating water ice and frozen atmosphere as a result of geothermal…
We propose a quantitative concept for the lower planetary boundary, requiring that a planet must keep its atmosphere in vacuum. The solution-set framework of Pecnik and Wuchterl (2005) enabled a clear and quantitative criterion for the…
While humans become more reliant on Earth's space environment, the potential for significant harm from severe space weather continues to grow. As structures from the sun reach Earth's magnetosphere and space environment, they deposit energy…