water world Archives - Page 12 of 14 - Astrobiology

Internal ocean probabilities of the investigated exoplanets. The colour bar depicts the probability of each planet having a liquid water reservoir in its interior. Red colours imply a high probability, while planets with dark blue circles are less likely to have internal oceans. The HZ, shown as a green band only for illustrative purposes, was calculated based on stellar parameters from theoretical stellar evolution models. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Proxima Centauri, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography

Water Content Of Rocky Exoplanets In The Habitable Zone

by Keith CowingDecember 4, 2023December 4, 2023

In this study we investigated the interiors of rocky exoplanets in order to identify those that may have large quantities of water.

An illustration of two water-rich exoplanets with hazy atmospheres. CREDIT Roberto Molar Candanosa/Johns Hopkins University.

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, Water/Hycean Worlds & Oceanography

An Alien Haze, Created In A Lab, Enables Better Viewing Of Distant Water Worlds

by Keith CowingNovember 27, 2023November 27, 2023

Scientists have simulated conditions that allow hazy skies to form in water-rich exoplanets, a crucial step in determining how haziness muddles observations by ground and space telescopes.

Outgoing thermal emission as a function of surface temperature. The dashed-dotted line is the classic runaway curve obtained with fully convective profiles, independently from the stellar radiation spectrum and internal flux. With self-consistent profiles, this function depends on the type of the host star and the internal flux ϕint. Dashed curves are obtained with Earth geothermal flux. For T-1 and ϕint < 0.01 Wm−2 , the runaway greenhouse can end without full vaporization of the ocean. Low-pressure liquidus, solidus and melting (melt fraction = 40%) temperatures are indicated for an Earth mantle composition. Surface pressure is 270 bars except in the blue area where Tsurf is below the critical temperature of H2O and psurf is given by the saturation vapor pressure of H2O. These curves are based on the profiles shown in Extended Data Figure 2 -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Lava / magma ocean / Volcanic Worlds, Status Report, Water/Hycean Worlds & Oceanography

A Cool Runaway Greenhouse Without Surface Magma Ocean

by Keith CowingNovember 17, 2023May 11, 2024

Water vapour atmospheres with content equivalent to the Earth’s oceans, resulting from impacts or a high insolation, were found to yield a surface magma ocean. This was, however, a consequence […]

Illustration of Earth’s interior revealing subducting water and a rising plume of magma. At the interface where subducting water meets the core, a chemical exchange occurs to form a hydrogen-rich layer in the topmost outer core and dense silica in the bottom of the mantle. Image courtesy Yonsei University

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Press Release, Water/Hycean Worlds & Oceanography

Surface Water Dives Deep And Transforms Earth’s Core’s Outer Layer

by Keith CowingNovember 15, 2023November 15, 2023

A few decades ago, seismologists imaging the deep planet identified a thin layer, just over a few hundred kilometers thick. The origin of this layer, known as the E prime […]

The mass-radius relations of the simulated planets from our migration and in-situ models both of which are found to explain the mass-radius relations of the observed planets. However, they predict completely different bulk compositions which can be reflected in the atmospheric composition. -- astro-ph.EP

Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

Where Are The Water Worlds? Identifying The Exo-water-worlds Using Models of Planet Formation and Atmospheric Evolution

by Keith CowingOctober 7, 2023October 7, 2023

Planet formation models suggest that the small exoplanets that migrate from beyond the snowline of the protoplanetary disk likely contain water-ice-rich cores (∼50% by mass), also known as the water […]

3D GCM output at 40◦ obliquity and H2=10% for the rain precipitation, snow and ice fraction at the surface, snowfall, sea/ground surface temperature. Black contour lines represent surface elevation level (-2000, 0, 2000 and 8000 meters) and the red contour line is the paleo-shoreline (-3900 meters). -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Mars, Status Report, Water/Hycean Worlds & Oceanography

Circumpolar Ocean Stability On Mars 3 Billion Years Ago

by Keith CowingOctober 3, 2023October 3, 2023

What was the nature of the Late Hesperian climate? Warm and wet or cold and dry? Formulated this way the question leads to an apparent paradox since both options seem […]

Initial and final atmospheric mass fraction Xatm and final water mole fraction (color bar) after the atmospheric loss through photoevaporation (ε = 0.1) for 4.6 Gyrs. The rocky core is composed of basalt (left panel), CI (middle panel), and EH (right panel). An initial water mass fraction is determined by the empirical relation derived from the giant impact simulations, XW = 8.2 × 10−2X −0.41 atm . The color contour shows the final H2O mole fraction in the remaining atmosphere. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Impact events, Status Report, Water/Hycean Worlds & Oceanography

Evolution of a Water-rich Atmosphere Formed by a Giant Impact on an Earth-sized Planet

by Keith CowingSeptember 28, 2023September 28, 2023

The atmosphere of a terrestrial planet that is replenished with secondary gases should have accumulated hydrogen-rich gas from its protoplanetary disk.

Water cloud horizontal and vertical distributions. Water cloud column (a) in latitude vs longitude coordinates and (b) tidallylocked coordinates (b). Water cloud content vertical distribution (c) as a function of tidally-locked latitude (averaged over all tidallylocked longitudes). The plots were computed for an initially hot and steamy 2 R⊕ planet (with a 10 bar of H2O + 1 bar of N2 atmosphere) synchronously rotating (fixed rotation period of 60 Earth days) around a M3 star, and forced to an ISR of 500 W m−2 (simulation M3-YANG-1). The outputs were averaged over 250 Earth days. For reference, insolation is 340.5 W m−2 on present-day Earth. Wind fields are superimposed on the plots. Winds are plotted at a pressure of ∼ 50 Pa in panels a and b, and averaged over all tidally-locked (TL) longitudes in panel c. -- astro-ph.EP

Astrochemistry, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography

Water Condensation Zones Around Main Sequence Stars

by Keith CowingAugust 29, 2023August 29, 2023

Understanding the set of conditions that allow rocky planets to have liquid water on their surface — in the form of lakes, seas or oceans — is a major scientific […]

Artist’s impression, frozen world with sub-surface ocean CREDIT Lujendra Ojha

Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Europa, Exoplanets, -moons, -comets, Habitable Zones, Press Release, Water/Hycean Worlds & Oceanography

Study Increases The Probability Of Finding Water On Other Worlds By x100

by Keith CowingJuly 11, 2023July 11, 2023

A new analysis shows that there are probably many more Earth-like exoplanets with liquid water than had been thought, significantly increasing the chance of finding life. The work finds that […]

This image, acquired on April 8, 2011, with the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on NASA’s Terra satellite, shows Saharan dust over the Bay of Biscay. A phytoplankton bloom makes the water appear bright green and blue. Sediment is likely contributing to some of the color, especially in coastal areas. Credits: NASA Earth Observatory image by Wanmei Liang, using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview.

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Desert Worlds, Gaia - Planetary Perspectives, Plant Biology, Press Release, Water/Hycean Worlds & Oceanography

How Desert Dust Nourishes The Growth Of Phytoplankton In Earth’s Oceans

by Keith CowingJuly 10, 2023August 23, 2025

For the past few decades, scientists have been observing natural ocean fertilization events — episodes when plumes of volcanic ash, glacial flour, wildfire soot, and desert dust blow out onto […]