There is growing evidence that brown dwarfs may be comparable to main-sequence stars in terms of their abundance. In this paper, we explore the prospects for the existence of life on Earth-like planets around brown dwarfs.
The pathways through which incoming energy is distributed between the surface and atmosphere has been analyzed for the Earth. However, the effect of the spectral energy distribution of a host star on the energy budget of an orbiting planet may be significant given the wavelength-dependent absorption properties of atmospheric CO2 and water vapor, and surface ice and snow.
The macroturbulent atmospheric circulation of Earth-like planets mediates their equator-to-pole heat transport.
Young terrestrial planets can capture or outgas hydrogen-rich atmospheres with tens to hundreds of bars of H2, which persist for 100 Myrs or longer.
The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) project is an instrument on the Subaru telescope that is pushing the frontiers of what is possible with ground-based high-contrast imaging of extrasolar planets.
L 98-59 (TIC 307210830, TOI-175) is a nearby M3 dwarf around which TESS revealed three terrestrial-sized transiting planets (0.80, 1.35, 1.57 Earth radii) in a compact configuration with orbital periods shorter than 7.5 days.
Scientists may have found a way to tell if alien worlds have a climate that is suitable for life by analyzing the light from these worlds for special signatures that are characteristic of a life-friendly environment.
Exoplanetary science is on the verge of an unprecedented revolution. The thousands of exoplanets discovered over the past decade have most recently been supplemented by discoveries of potentially habitable planets around nearby low-mass stars.
State of the art spectral retrieval models of exoplanet atmospheres assume constant chemical profiles with altitude.
Planned astronomical observatories of the 2020s will be capable of obtaining reflected light photometry and spectroscopy of cool extrasolar giant planets.
L-type and T-type dwarfs span the boundaries between main-sequence stars, brown dwarfs, and planetary-mass objects.
We report the Transiting Exoplanet Survey Satellite (TESS) discovery of three terrestrial-sized planets transiting L 98-59 (TOI-175, TIC 307210830) -- a bright M dwarf at a distance of 10.6 pc.
How good is our universe at making habitable planets? The answer to this depends on which factors are important for life: Does a planet need to be Earth mass? Does it need to be inside the temperate zone?
We report improved masses, radii, and densities for four planets in two bright M-dwarf systems, K2-3 and GJ3470, derived from a combination of new radial velocity and transit observations. Supplementing K2 photometry with follow-up Spitzer transit observations refined the transit ephemerides of K2-3 b, c, and d by over a factor of 10.
Transit spectroscopy of terrestrial planets around nearby M dwarfs is a primary goal of space missions in coming decades. 3-D climate modeling has shown that slow-synchronous rotating terrestrial planets may develop thick clouds at the substellar point, increasing the albedo.
By generalizing the theory of convection to any type of thermal and compositional source terms (diabatic processes), we show that thermohaline convection in Earth oceans, fingering convection in stellar atmospheres, and moist convection in Earth atmosphere are deriving from the same general diabatic convective instability.
Directly-imaged planetary-mass companions offer unique opportunities in atmospheric studies of exoplanets. They share characteristics of both brown dwarfs and transiting exoplanets, therefore, are critical for connecting atmospheric characterizations for these objects.
We present significant differences in the simulated atmospheric flow for warm, tidally-locked small Neptunes and super Earths (based on a nominal GJ 1214b) when solving the simplified, and commonly used, primitive dynamical equations or the full Navier-Stokes equations.
Every school kid knows that Earth has a magnetic field -- it's what makes compasses align north-south and lets us navigate the oceans. It also protects the atmosphere, and thus life, from the Sun's powerful wind.
The search for Earth-like planets around Sun-like stars and the evaluation of their occurrence rate is a major topic of research for the exoplanetary community.