Proxima Cen (GJ 551; dM5.5e) is one of only about a dozen fully convective stars known to have a stellar cycle, and the only one to have long-term X-ray monitoring.
Radiation
Posted inAstronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Radiation, Space Weather & Heliophysics, Status Report, TRAPPIST-1
An Experimental Study Of The Biological Impact Of A Superflare On The TRAPPIST-1 Planets
In the present study, we conducted experiments to assess the biological effects of high fluences of UV radiation (UVR) on the TRAPPIST-1 planetary system (planets e, f, g within the […]
![Images of cells via optical microscopy for 95-level (a), and via fluorescence microscopy combined with SYTO-9 staining for the (b) 101-level, (c) 1200-level, and (d) service water. Scale bar on the lower right of each image represents 5 μm. Magnification was 50x for (a) and 1000x for (b), (c) and (d). Cells in (a) are circular features entrapped in halite fluid inclusions and identified by red arrows. Cells in (b), (c), and (d) appear as bright green shapes. In (b), green background fluorescence highlights the high level of dissolved organic carbon debris for this sample [29]. Cell counts for the 95-, 101-, service water, and 1200-levels were 102 cells/mL ±10, 104 cells/mL ± 102, 106 cells/mL ± 104.5, 105 cells/mL ±103.3, respectively (error in standard deviation). A schematic is included to the right showing the depth and major lithology of fluid sampling sites considered in this study. -- ISME Communications](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/11/Radiolytic-Support-For-Oxidative-Metabolism-In-An.png?resize=1200%2C719&ssl=1)
Posted inBiochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Extremeophiles and Extreme Environments, Habitable Zones, Origin & Evolution of Life, Radiation, Status Report
Radiolytic Support For Oxidative Metabolism In An Ancient Subsurface Brine System
Long-isolated subsurface brine environments (Ma-Ga residence times) may be habitable if they sustainably provide substrates, e.g. through water-rock reaction, that support microbial catabolic energy yields exceeding maintenance costs.
Posted inAnalog Studies, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Mars, Radiation, Status Report
Rapid Destruction of Lipid Biomarkers Under Simulated Cosmic Radiation
Understanding how organics degrade under galactic cosmic rays (GCRs) is critical as we search for traces of ancient life on Mars.
Posted inEuropa, Ganymede, Icy Worlds, Jupiter, Microbiology & Virology, Missions & Hardware, Planetary Protection & Biosafety, Radiation, Status Report, Water/Hycean Worlds & Oceanography
Europa Clipper Planetary Protection Probabilistic Risk Assessment Summary
Protecting Jupiter’s Icy Moons from the Earth’s biological contamination is a key consideration for the Europa Clipper mission. The mission’s goal is to explore Jupiter’s moon, Europa, and investigate its […]
Posted inAstrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Imaging & Spectroscopy, Interstellar, Radiation, Status Report
Neural Network Constraints on the Cosmic-Ray Ionization Rate and Other Physical Conditions in NGC 253 with ALCHEMI Measurements of HCN and HNC
We use a neural network model and ALMA observations of HCN and HNC to constrain the physical conditions, most notably the cosmic-ray ionization rate (CRIR, zeta), in the Central Molecular […]
Posted inBiosignatures & Paleobiology, Cryobiology, Extremeophiles and Extreme Environments, Habitable Zones, Mars, Microbiology & Virology, Press Release, Radiation
Potential Microbial Habitats In Martian Ice
Dusty ice exposed at the surface of Mars could provide the conditions necessary for the presence of photosynthetic life, according to a modelling study. The findings, published in Communications Earth […]
Posted inHabitable Zones, Magnetic Fields, Electromagnetism, bioelectricity,, Radiation, Space Weather & Heliophysics, Status Report
Space Weather Forecasts: Monitoring The Daily Variation of Sun-Earth Magnetic Fields Using Galactic Cosmic Rays
The interplanetary magnetic field (IMF) between the Sun and Earth is an extension of the solar magnetic field carried by the solar wind into interplanetary space.
Posted inGaia - Planetary Perspectives, Jupiter, Magnetic Fields, Electromagnetism, bioelectricity,, Missions & Hardware, Press Release, Radiation, Space Weather & Heliophysics
NASA Instruments On ESA Juice Astrobiology Probe Image Earth’s Radiation Belt
From Aug. 19-20, ESA’s (European Space Agency’s) Juice (Jupiter Icy Moons Explorer) mission made history with a daring lunar-Earth flyby and double gravity assist maneuver, a spaceflight first. As the […]
Posted inAstronomy & Telescopes, Interstellar, Missions & Hardware, Press Release, Radiation
Voyager 2 Interstellar Probe Science Instrument Turned Off To Save Power
The Voyager 2 mission has been working to postpone the shut-off as long as possible. Four other instruments aboard the interstellar spacecraft continue to operate.