magnetite Archives

A Sulawesi Island with location of the Malili Lake System (insert

Metagenomics Deciphers Diagenetic Processes Of Ferruginous Mineralization In The Deep Biosphere

by Keith CowingAugust 20, 2026August 20, 2026

[Nature Communications Earth & Environment] Ferruginous conditions in the Precambrian oceans gave rise to ancient iron formations that contain the oldest recognized traces of life in the form of mineral […]

Magnetite formation under prebiotically plausible conditions. a Envisioned evaporative lake setting on early Earth, where magnetite likely formed via authigenic precipitation facilitated either by solar irradiation or nitrogen oxide from the decomposition of abiotic nitrogen fixation products [62]. As these magnetite particles form, they acquire a natural remanent magnetization under the geomagnetic field. b Experimental setup used to reproduce early Earth conditions and investigate magnetite formation under UV-facilitated synthesis (samples UV1 to UV3) and c via nitrite oxidation of Fe(II) (samples NUV8 and NUV9). Samples NUV5 to NUV7 were synthesized by mixing Fe(II) and Fe(III) with different proportions (10%/90%, 50%/50% and 90%/10% of Fe(II)/Fe(III), respectively). -- physics.chem-ph

Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Origin & Evolution of Life, Status Report

Prebiotic Magnetite Enables Chirality-magnetic Surface Feedback

by Keith CowingMay 27, 2026May 27, 2026

The emergence of biomolecular homochirality requires both an initial symmetry-breaking event and a mechanism to amplify and preserve a chiral imbalance.

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Press Release

Hayabusa2 Asteroid Samples Offer New Insights Into Conditions When The Solar System Formed

by Keith CowingMarch 4, 2026March 4, 2026

To uncover the history of our solar system, it is necessary to study the dynamic evolution of the ancient solar nebula materials.

Spectral slope versus the size of the observed Pallas family members. The spectral slopes are calculated from Gaia’s Data Release 3 (DR3) observations (Gaia Collaboration et al. 2016, 2023b) and the sizes are obtained from the 2019 NEOWISE diameters and albedos archive. -- astro-ph.EP

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Status Report

Near-infrared Spectroscopic Characterization Of The Pallas Family

by Keith CowingMarch 18, 2025March 18, 2025

The Pallas collisional family of asteroids, named after (2) Pallas, is notable for its high orbital inclination and the distinct blue color of Pallas and a few larger B-type family […]

The opened science canister in the glovebox at JSC. The cylindrical TAGSAM head is positioned in the center of the avionics deck. Dark particles and dust can be seen on the avionics deck, the top of TAGSAM (including on circular witness plates), and the inside of the canister's lid. NASA

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Imaging & Spectroscopy, Meteorites & Asteroids, Missions & Hardware, Planetary Protection & Biosafety, Sample Return, Status Report

Asteroid Bennu: Properties Of The Sample Collected By OSIRIS-REx

by Keith CowingJuly 8, 2024July 7, 2024

On September 24, 2023, NASA’s OSIRIS-REx mission dropped a capsule to Earth containing ~120 g of pristine carbonaceous regolith from Bennu. We describe the delivery and initial allocation of this asteroid […]

Hydrothermal vents on the ocean floor, known as black smokers, emit volcanically heated fluids rich in dissolved metals and sulfur. These environments are oases of microbial activity on the ocean floor. -- Marum Universitat of Bremen

Atmospheres, Climate, Weather, Away Teams & Field Reports, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Exploration Gear & Tech, Extremeophiles and Extreme Environments, Habitable Zones, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Microbiology & Virology, Origin & Evolution of Life, Press Release, Robotics/Rovers/UAVs, ROVs/Submersibles/Diving, Water/Hycean Worlds & Oceanography

Iron-sulfur Minerals Bear Witness To The Earliest Life On Earth

by Keith CowingMay 31, 2024May 31, 2024

A team of researchers at the Universities of Tübingen and Göttingen has found that certain minerals with characteristic shapes could indicate the activity of bacteria in hydrothermal vents – or […]

Magnetite (round particles) particles cut from a Ryugu sample. (A) Bright field transmission electron microscopy image. (B) Magnetic flux distribution image obtained by electron holography. The concentric circular stripes seen inside the particles correspond to magnetic lines of force. They are called vortex magnetic domain structures and are more stable than ordinary hard disks, which can record magnetic fields for more than 4.6 billion years. (Yuki Kimura, et al. Nature Communications. April 29, 2024) CREDIT Yuki Kimura, et al. Nature Communications. April 29, 2024

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Comets and Asteroids, Imaging & Spectroscopy, Press Release, Space Weather & Heliophysics

Probing The Effects Of Interplanetary Space On Asteroid Ryugu

by Keith CowingApril 29, 2024April 29, 2024

Samples reveal evidence of changes experienced by the surface of asteroid Ryugu, some probably due to micrometeoroid bombardment.

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Exploration Gear & Tech, Meteorites & Asteroids, Missions & Hardware, Sample Return, Status Report

Asteroid (101955) Bennu In The Laboratory: Properties Of The Sample Collected By OSIRIS-REx

by Keith CowingApril 22, 2024April 22, 2024

On 24 September 2023, the NASA OSIRIS-REx mission dropped a capsule to Earth containing approximately 120 g of pristine carbonaceous regolith from Bennu.

A The scanning electron micrograph and (B, C) transmission electron micrographs of MTB. White arrows indicate magnetosome chains, and white triangles indicate granules. D Terrestrial extremotolerant MTB and implications for ancient Mars. MTB are found to be able to resist various hostile settings, such as irradiation, hypomagnetic exposure, microgravity, metal stress, hypersalinity, acidic/hyperalkaline pH, and freezing/moderately hyperthermal temperatures. MTB emerged early in Earth’s history. Since ancient Mars was also characterized by many MTB-favorable aquatic/sediment oxic-anoxic conditions and a global magnetic field, it is proposed that Mars may have harbored MTB-like life in the past. -- The ISME Journal

Astrochemistry, Astrogeology, Mars, Meteorites & Asteroids, Status Report

Renaissance For Magnetotactic Bacteria In Astrobiology

by Keith CowingFebruary 8, 2024February 8, 2024

Capable of forming magnetofossils similar to some magnetite nanocrystals observed in the Martian meteorite ALH84001, magnetotactic bacteria (MTB) once occupied a special position in the field of astrobiology during the […]

a, Backscattered electron image of a fine Ryugu grain. The white boxes correspond to the areas shown in b and c. b, Secondary electron image of framboidal magnetite showing granular texture. c, Secondary electron image of porous iron sulfide surrounded by phyllosilicate. The arrow points to an iron whisker on the iron sulfide surface. Sample ID is A0104-021012.

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Origin & Evolution of Life, Press Release

Meteorites Were A Likely Source Of Nitrogen For Early Earth

by Keith CowingDecember 2, 2023December 2, 2023

Micrometeorites originating from icy celestial bodies in the outer Solar System may be responsible for transporting nitrogen to the near-Earth region in the early days of our solar system. That […]