Planet-planet occultations (PPOs) occur when one exoplanet occults another exoplanet in the same system as seen from the Earth’s vantage point. PPOs may provide a unique opportunity to observe radio […]
TRAPPIST-1
Posted inAtmospheres, Climate, Weather, Exoplanets, -moons, -comets, Habitable Zones, Status Report, TRAPPIST-1
Nightside Clouds on Tidally-locked Terrestrial Planets Mimic Atmosphere-Free Scenarios
We investigate the impact of nightside cloud formation on the observable night-day contrast of tidally-locked terrestrial planet atmospheres.
Posted inBiophysics, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Proxima Centauri, Radiation, Space Weather & Heliophysics, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography
The Time Evolution Of The Ultraviolet Habitable Zone
For stars hosting Circumstellar Habitable Zone (CHZ) exoplanets, we investigate the time-evolution of their ultraviolet habitable zone (UHZ), the annular region around a star where an exoplanet could experience a […]
![Joining of the inner and outer subsystems. The evolution of the semi-major axes is shown with continuous coloured lines for all planets, which are also labelled by circles whose size reflect the observed size of the planets. In our favoured scenario, planet e followed the inner edge while planets b, c and d were in the inner cavity. Planets f, g and h join the system later, undergoing inward disc-driven migration (the disc is depicted by the top shaded area, with the lighter shading on the right indicating that the disc will eventually disperse). Since planet g is more massive than f and h, it is likely to capture f in resonance (the 4:3 being the favoured commensurability [5]) and the two planets migrate in together. When f reaches the 3:2 resonance with e, the combined push from g-f is sufficient to dislodge planet e from the inner edge (shown as a blue line enclosing the top shaded area). Driven by a full OLT, the orbit of planet e decays faster than f and g, approaching the 3:2 resonance with d. Planet h is the last one to migrate in and capture g in the 3:2 resonance to complete the chain. -- astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/08/Forming-the-Trappist-1-system.png?resize=1200%2C720&ssl=1)
Posted inExoplanets, -moons, -comets, Status Report, TRAPPIST-1
Forming The Trappist-1 System In Two Steps During The Recession Of The Disc Inner Edge
Trappist-1 hosts 7 planets where period ratios of neighbouring pairs are close to the 8:5, 5:3, 3:2, 3:2, 4:3, and 3:2 ratios in increasing distance from the star. The Laplace […]
Posted inAstrochemistry, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Proxima Centauri, Status Report, TRAPPIST-1
STScI Initiates A Concerted Search For Atmospheres Around M-dwarf Exoplanets
The STScI Director, Dr. Jennifer Lotz, has accepted the primary recommendation of the Working Group on Strategic Exoplanet Initiatives , and has decided to proceed with a large-scale survey of […]
Posted inAstrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography
How Land-Mass Distribution Influences the Atmospheric Dynamics of Tidally Locked Terrestrial Exoplanets
Interpretation of the ongoing efforts to simulate the atmospheres of potentially-habitable terrestrial exoplanets requires that we understand the underlying dynamics and chemistry of such objects to a much greater degree […]
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Press Release, TRAPPIST-1
Asymmetries In The Simulated Ozone Distribution On TRAPPIST-1e Due To Orography
TRAPPIST-1e is a tidally locked rocky exoplanet orbiting the habitable zone of an M dwarf star. Upcoming observations are expected to reveal new rocky exoplanets and their atmospheres around M […]
Posted inAstrochemistry, Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, SETI & Technosignatures, Terraforming & Geoengineering, TRAPPIST-1
Telltale Greenhouse Gases Could Signal Alien Terraforming Activity
If aliens modified a planet in their solar system to make it warmer, we’d be able to tell. A new UC Riverside study identifies the artificial greenhouse gases that would […]
Posted inAstrochemistry, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography
Transmission Spectroscopy of the Habitable Zone Exoplanet LHS 1140 b with JWST/NIRISS
LHS 1140 b is the second-closest temperate transiting planet to the Earth with an equilibrium temperature low enough to support surface liquid water.
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography
A Formation Pathway For Terrestrial Planets With Moderate Water Content Involving Atmospheric-volatile Recycling
Of the many recently discovered terrestrial exoplanets, some are expected to harbor moderate water mass fractions of a few percent. The formation pathways that can produce planets with these water […]