[astro-ph.EP] Given their abundance and observational advantages, M stars will arguably be the best candidates for characterizing and searching for biosignatures on terrestrial exoplanets in the near future.
biosignature
Posted inBiosignatures & Paleobiology
Direct Dating Of 3.5 Ga Biogenic Carbon In A Microbial Mat Remnant, Singhbhum Craton, India
[PNAS]. Kerogen, insoluble organic matter preserved in sediments, represents some of the earliest known terrestrial biosignatures which have provided important insights into the origin of life and planetary habitability.
![The best-fit chemical equilibrium models to our co-added data performed with three different retrieval suites. For all chemical equilibrium fits, the models produced poor fits to several features on the spectrum, namely near 3 µm and between 4 − 5 µm region. For the 4.3 micron region, the differences between features are due to a combination of differences in the retrieval framework (namely prior constraints) and chemical networks used (FastChem vs GGChem) for each retrieval suite. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/GEMS-JWST.png?resize=1200%2C719&ssl=1)
Posted inExoplanets, -moons, -comets
GEMS JWST: HATS(-6 b): A Sub-solar Metallicity Giant Planet With Water, Methane And Ammonia In Its Atmosphere
[astro-ph.EP] HATS-6 b is one of several recently discovered Giant Exoplanets orbiting M-dwarf Stars (GEMS) and is part of a JWST survey that aims to compare bulk and atmospheric properties […]
![This illustration contrasts Earth's oceans during ancient glaciations (left) with deglacial conditions (right). Syracuse University researchers found that oceans lost oxygen not just during warm periods, but repeatedly during Earth's deepest ice ages, a pattern preserved in manganese deposits within ancient seafloor rock. (Courtesy: Xubin Wang, generated with AI)-- [Syracuse University]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Metal-deposits.jpg?resize=1200%2C720&ssl=1)
Posted inBiogeochemical Cycles & Geobiology
Metal Deposits Linked To Oceanic Oxygen Loss During Ancient Ice Ages
[Syracuse University] An international team of researchers analyzed manganese and other chemical signatures preserved in more than 27,000 ancient seafloor samples collected from six continents. Across six major glaciations spanning […]
JPL and the Search for Life Beyond Earth
Registration is limited to 1000 participants. Register early to reserve your spot. Free livestream | Open to the public REGISTER In September 2025, a sample named Sapphire Canyon made headlines […]
Posted inBiosignatures & Paleobiology
Assessing Cell Survival And Biosignature Preservation Of The Extremely Thermoacidophilic Archaeon Acidianus Manzaensis After Exposure To Mars-like Conditions
[FEMS Microbes via PubMed] Considering the harsh surface conditions on Mars, terrestrial organisms that can survive and remain detectable after exposure to similar conditions provide invaluable models for guiding current […]
Posted inBiosignatures & Paleobiology
Emergence Of Biosignatures On Earth And Implications For Life Detection
[PNAS] Earth’s organic chemical evolution (OCE) from abiotic to prebiotic to biotic provides critical insights that may have implications for how we interpret observations made by life-detection planetary missions.
Posted inExoplanets, -moons, -comets
Strict Limits On Helium Absorption From LHS 1140 b From Four JWST NIRISS Transits
[astro-ph.EP] Orbiting in the habitable zone of its host star, the 1.7 R⊕, 5.6 M⊕ planet LHS 1140 b is a target of great interest.
Posted inAstronomy & Telescopes
NASA ROSES-25 Amendment 69: New Opportunity: D.9 Habitable Worlds Observatory Instrument Concept Assessments
[NASA] Habitable Worlds Observatory (HWO) Instrument Concept Assessments (HWO-ICA) program element D.9 of ROSES-25, solicits proposals to support maturation of the HWO mission concept. The objective of HWO-ICA is to […]
Posted inNASA Astrobiology Program
Astrobiology: Fifty Years After Viking: New Special Collection Available Now
Guest edited by Dr. Scott M. Perl (LA-NHM) and Dr. Mary Beth Wilhelm (NASA Ames) To mark the 50th anniversary of NASA’s Viking landings, the journal Astrobiology has published a […]