• Publications
  • Influence
The ongoing discoveries of extra-solar planets are unveiling a wide range of terrestrial mass (size) planets around their host stars. In this Letter, we present estimates of habitable zones (HZs)Expand
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Identifying terrestrial planets in the habitable zones (HZs) of other stars is one of the primary goals of ongoing radial velocity (RV) and transit exoplanet surveys and proposed future spaceExpand
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Warming early Mars with CO 2 and H 2
Ancient valleys suggest a warm early Mars where liquid water flowed, but a greenhouse effect strong enough to offset a dim early Sun has been difficult to explain. Climate simulations suggest thatExpand
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The geological and climatological case for a warmer and wetter early Mars
The climate of early Mars remains a topic of intense debate. Ancient terrains preserve landscapes consistent with stream channels, lake basins and possibly even oceans, and thus the presence ofExpand
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Can increased atmospheric CO2 levels trigger a runaway greenhouse?
Recent one-dimensional (globally averaged) climate model calculations by Goldblatt et al. (2013) suggest that increased atmospheric CO(2) could conceivably trigger a runaway greenhouse on presentExpand
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Remote life-detection criteria, habitable zone boundaries, and the frequency of Earth-like planets around M and late K stars
Significance National Aeronautics and Space Administration’s (NASA) Kepler Space Telescope has detected over 3,000 planet candidates, about a dozen of which are probably rocky planets within theExpand
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The Habitable Zones of Pre-Main-Sequence Stars
We calculate the pre-main-sequence HZ for stars of spectral classes F to M. The spatial distribution of liquid water and its change during the pre-main-sequence phase of protoplanetary systems isExpand
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A More Comprehensive Habitable Zone for Finding Life on Other Planets
The habitable zone (HZ) is the circular region around a star(s) where standing bodies of water could exist on the surface of a rocky planet. Space missions employ the HZ to select promising targetsExpand
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A warmer and wetter solution for early Mars and the challenges with transient warming
  • R. Ramirez
  • Environmental Science, Physics
  • 27 June 2017
Abstract The climate of early Mars has been hotly debated for decades. Although most investigators believe that the geology indicates the presence of surface water, disagreement has persistedExpand
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Impact of Space Weather on Climate and Habitability of Terrestrial Type Exoplanets
The search for life in the Universe is a fundamental problem of astrobiology and modern science. The current progress in the detection of terrestrial-type exoplanets has opened a new avenue in theExpand
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