相关论文: A Methane Extension to the Classical Habitable Zon…
Planets similar to Earth - but slightly more irradiated - are expected to enter into a runaway greenhouse state, where all surface water rapidly evaporates, forming an optically thick H2O-dominated atmosphere. For Earth, this extreme…
The forcings due to changing concentrations of Earth's five most important, naturally occurring greenhouse gases, H$_2$O, CO$_2$, O$_3$, N$_2$O and CH$_4$ as well as CF$_4$ and SF$_6$ were evaluated for the case of a cloud-free atmosphere.…
A general formulation to compute habitable zones (HZ) around binary stars is presented. A HZ in this context must satisfy two separate conditions: a radiative one and one of dynamical stability. For the case of single stars, the usual…
Massive stars dominate the radiative and mechanical feedback of young stellar populations, yet their intense ultraviolet fields and strong winds are typically presumed to preclude Earth-like habitability. We quantify this expectation by…
CH2 transitions between 68 and 71 GHz were first detected toward the Orion-KL and W51 Main SFRs. Given their upper level energies of 225 K, they were thought to arise in dense, hot molecular cores near newly formed stars. However, this has…
In exoplanet research, the focus is increasingly on identifying Earth analogs, planets similar in density and habitability potential. As the number of rocky exoplanets grows, parallel discussions have emerged on system architectures and…
Earth systems may fall into an undesirable system state if 1.5 degrees celsius (C) of warming is exceeded. Carbon release from substantial permafrost stocks vulnerable to near-term warming represents a positive climate feedback that may…
In the search for life in the Universe, molecular oxygen (O$_2$) combined with a reducing species, such as methane (CH$_4$), is considered a promising disequilibrium biosignature. In cases where it would be difficult or impossible to detect…
Carbon is an essential element for life on Earth, and the relative abundances of major carbon species (CO2, CO, and CH4) in the atmosphere exert fundamental controls on planetary climate and biogeochemistry. Here, we employed a theoretical…
Planetary atmospheric energy budgets primarily depend on stellar incident flux. However, stellar variability can have major consequences for the evolution of planetary climates. In this work, we evaluate how stellar variability influences…
Discoveries of extrasolar planets in the habitable zone (HZ) of their parent star lead to questions about the habitability of massive moons orbiting planets in the HZ. Around low-mass stars, the HZ is much closer to the star than for…
We use a three-dimensional model to calculate steady-state climates at various intervals in Earth's future, across a parameter space of increasing insolation and decreasing CO$_2$ mixing ratio. Comparison with prior results shows an…
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…
Uncovering the occurrence rate of terrestrial planets within the Habitable Zone (HZ) of their host stars has been a particular focus of exoplanetary science in recent years. The statistics of these occurrence rates have largely been derived…
Monitoring the abundance of greenhouse gases (GHGs) such as carbon dioxide (CO$_2$) and methane (CH$_4$) is necessary to quantify their impact on global warming and climate change. Although a number of satellites and ground-based networks…
The Galactic habitable zone is defined as the region with highly enough metallicity to form planetary systems in which Earth-like planets could be born and might be capable of sustaining life surviving to the destructive effects of nearby…
Terrestrial planets currently in the habitable zones around M dwarfs likely experienced a long-term runaway greenhouse condition because of a slow decline in host-stellar luminosity in its pre-main sequence phase. Accordingly, they might…
Understanding the surface and atmospheric conditions of Earth-size, rocky planets in the habitable zones (HZs) of low-mass stars is currently one of the greatest astronomical endeavors. Knowledge of the planetary effective surface…
Since there are several ways planets can survive the giant phase of the host star, we examine the habitability and detection of planets orbiting white dwarfs. As a white dwarf cools from 6000 K to 4000 K, a planet orbiting at 0.01 AU would…
High-resolution spectra of Pluto in the 1.66 um region, recorded with the VLT/CRIRES instrument in 2008 (2 spectra) and 2012 (5 spectra), are analyzed to constrain the spatial and vertical distribution of methane in Pluto's atmosphere and…