Biogeochemical Cycles & Geobiology Archives

Schema of the sub-grid scale slope parameterization. Each mesh of the Mars PCM is decomposed into sub-grid slopes (defined by characteristic slopes µi) or flat terrain. These subgrid terrains have their microclimate and the interactions between the atmosphere and surface are made through averaged values over the mesh. -- astro-ph.EP

Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Habitable Zones, Mars, Status Report

Modelling Slope Microclimates In The Mars Planetary Climate Model

by Keith CowingJune 28, 2023June 28, 2023

A large number of surface phenomena (e.g., frost and ice deposits, gullies, slope streaks, recurring slope lineae) are observed on Martian slopes.

Model transmission spectrum of our canonical Hycean world K2-18 b. The model spectrum with all the molecules included is shown in grey. The spectra with the individual contributions of the different molecular species are shown as denoted in the legend. The synthetic JWST observations corresponding to the full model are shown as the gold-centered black points with error bars binned to a resolution of R= 40. The observations include one transit with NIRISS SOSS, three transits with NIRSpec G395H and two transits with MIRI LRS, as discussed in section 4. -- astro-ph.EP

Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography

Chemical Conditions On Hycean Worlds

by Keith CowingJune 26, 2023June 26, 2023

Traditionally, the search for life on exoplanets has been predominantly focused on rocky exoplanets. Hycean worlds are a class of habitable sub-Neptunes with planet-wide oceans and H2-rich atmospheres. Their broad […]

Timescale for isotope exchange reaction, τ, as a function of Pwater and vrel (solid lines). The vertical dashed line represents vrel at s16 = 0.2 (see Section 3.1.2). Here, we set T = 2000 K, r = 0.5 mm, χ = 1, and β16 = 0.3. The dashed lines represent the timescale of homogenization, τhomo, as a function of PH2 and vrel (see Section 4.2). -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Status Report

Oxygen Isotope Exchange Between Molten Silicate Spherules and Ambient Water Vapor with Nonzero Relative Velocity: Implication for Chondrule Formation Environment

by Keith CowingJune 26, 2023June 26, 2023

Oxygen isotope compositions of chondrules reflect the environment of chondrule formation and its spatial and temporal variations.

Large green blooms of phytoplankton swirl in the dark water around Gotland, a Swedish island in the Baltic Sea. Credits: USGS/NASA/Landsat 7

Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Plant Biology, Press Release

Identifying Phytoplankton Species From Orbit

by Keith CowingJune 25, 2023June 25, 2023

Editor’s note: As our ability to study the characteristics of exoplanets that might be habitable increases, the need for metrics whereby various life forms can be discovered i.e. biosignatures – […]

Judith Su of biomedical enginering and optical sciences and engineering is a recipient of a 2023 CAREER Award from the National Science Foundation.

Away Teams & Field Reports, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exploration Gear & Tech, Press Release, Tricorders & Sensors

Tricorder Tech: Developing A Bioinspired Optical Sniffer Sensor

by Keith CowingJune 24, 2023June 24, 2023

Editor’s note: If you are on a long term mission or on an away team on another world, you might want your tricorder to be able to do some quick […]

Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life, Press Release

Discovery Of Novel Primitive Xeno Nucleic Acids As Alternative Genetic Polymers

by Keith CowingJune 23, 2023June 23, 2023

The chemical origin of life on Earth is a puzzle that scientists have been trying to piece together for decades. Many hypotheses have been proposed to explain how life came […]

Asteroid Itokawa as seen by the Hayabusa spacecraft. The peanut-shaped S-type asteroid measures approximately 1,100 feet in diameter and completes one rotation every 12 hours. -- JAXA

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Status Report

Asteroid Itokawa Once Supported a Hydrothermal System

by Keith CowingJune 23, 2023June 23, 2023

Ordinary chondrites (OCs) are the most abundant type of meteorites that fall to Earth. Compared to the carbonaceous chondrites, which commonly contain abundant hydrous minerals, OCs consist mainly of anhydrous […]

Artist impression showing the exoplanet LP 890-9c’s potential evolution from a hot Earth to a desiccated Venus. Carl Sagan Institute/R. Payne

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Press Release, TRAPPIST-1, Venus, Water/Hycean Worlds & Oceanography

Exoplanet LP 890-9c May Reveal Secrets About The Edge Of Habitability

by Keith CowingJune 21, 2023June 21, 2023

How close can a rocky planet be to a star, and still sustain water and life? A recently discovered exoplanet may be key to solving that mystery.

Time-mean vertically-integrated cloud water amount (including both liquid and ice) simulated by the three models. Left panels are for TRAPPIST-1e, and right panels are for K2-72e. The global-mean values are listed in the top left corner of each panel. The red cross marks the substellar point. The blue dashed line is the morning terminator and the blue dotted line is the evening terminator, used for transmission spectra calculations (Fig. 6 below). SAM has less total cloud water path. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Imaging & Spectroscopy, Status Report

Cloud Behaviour On Tidally Locked Rocky Planets From Global High-resolution Modeling

by Keith CowingJune 21, 2023June 21, 2023

Determining the behaviour of convection and clouds is one of the biggest challenges in our understanding of exoplanetary climates.

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Enceladus, Icy Worlds, Press Release, Water/Hycean Worlds & Oceanography

Phosphate, A Key Building Block Of Life, Found On Saturn’s Moon Enceladus

by Keith CowingJune 18, 2023June 16, 2023

An international team including a University of Washington scientist has found that the water on one of Saturn’s moons harbors phosphates, a key building block of life. The team led […]