Results tagged “habitabiility”

Synchronously orbiting, tidally-locked exoplanets with a dayside facing their star and a permanently dark nightside orbiting dim stars are prime candidates for habitability. Simulations of these planets often show the potential to maintain an Earth-like climate with a complete hydrological cycle.

The search for life in the universe is currently focused on Earth-analog planets. However, we should be prepared to find a diversity of terrestrial exoplanets not only in terms of host star but also in terms of surface environment.

Are there hurricanes on exoplanets? Tidally locked terrestrial planets around M dwarfs are the main targets of space missions for finding habitable exoplanets. Whether hurricanes can form on this kind of planet is important for their climate and habitability.

Tidally locked terrestrial planets around low-mass stars are the prime targets of finding potentially habitable exoplanets.

Stellar evolution models predict that the solar luminosity was lower in the past, typically 20-25 % lower during the Archean (3.8-2.5 Ga). Despite the fainter Sun, there is strong evidence for the presence of liquid water on Earth's surface at that time.

Whether there is life elsewhere in the universe is a question people have pondered for millennia; and within the last few decades, great strides have been made in our search for signs of life outside of our solar system.

The next generation of powerful Earth- and space-based telescopes will be able to hunt distant solar systems for evidence of life on Earth-like exoplanets - particularly those that chaperone burned-out stars known as white dwarfs.

A team of transatlantic scientists, using reanalyzed data from NASA's Kepler space telescope, has discovered an Earth-size exoplanet orbiting in its star's habitable zone, the area around a star where a rocky planet could support liquid water.

The habitable zone is the main tool that mission architectures utilize to select potentially habitable planets for follow up spectroscopic observation.

Although habitability, defined as the general possibility of hosting life, is expected to occur under a broad range of conditions, the standard scenario to allow for habitable environments is often described through habitable zones (HZs).

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.

The characterization of rocky, Earth-like planets is an important goal for future large ground- and space-based telescopes.

Disequilibria From Dead To Living Worlds

Chemical disequilibrium in exoplanetary atmospheres (detectable with remote spectroscopy) can indicate life.

Planets residing in circumstellar habitable zones (CHZs) offer our best opportunities to test hypotheses of life's potential pervasiveness and complexity.

Correct estimates of stellar extreme ultraviolet (EUV; 100 - 1170 Å) flux are important for studying the photochemistry and stability of exoplanet atmospheres, as EUV radiation ionizes hydrogen and contributes to the heating, expansion, and potential escape of a planet's upper atmosphere.

Investigating the atmospheres of rocky exoplanets is key to performing comparative planetology between such worlds and the terrestrial planets that reside in the inner Solar System.

In the past decade, observations from space and ground have found H2O to be the most abundant molecular species, after hydrogen, in the atmospheres of hot, gaseous, extrasolar planets. Being the main molecular carrier of oxygen, H2O is a tracer of the origin and the evolution mechanisms of planets.

Astronomical calculations reveal the solar system's dynamical evolution, including its chaoticity, and represent the backbone of cyclostratigraphy and astrochronology.

This paper reviews habitability conditions for a terrestrial planet from the point of view of geosciences. It addresses how interactions between the interior of a planet or a moon and its atmosphere and surface (including hydrosphere and biosphere) can affect habitability of the celestial body.

The frequency of Earth-size planets in the habitable zone of Sun-like stars, hereafter η⊕, is a key parameter to evaluate the yield of nearby Earth analogues that can be detected and characterized by future missions.

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