ArticleAstrobiology2016
The Pale Orange Dot: The Spectrum and Habitability of Hazy Archean Earth.
Article in Astrobiology, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 30 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
30 citing papers in PubMed, 301 citations in OpenAlex.
- Photochemistry and haze in chemically reducing terrestrial atmospheres.Fundamental research · 2026Review
- What the Solar System Can Teach Us About Rocky Exoplanets.Space science reviews · 2026Review
- Is a constitutive red-shift an advantage for oxygenic photosynthesis under M dwarf starlight? Insights fromFEMS microbes · 2026Article
- Transient oxidation of hazes a source of nutrients during the great oxidation event.Scientific reports · 2025Article
- Co-evolution of early Earth environments and microbial life.Nature reviews. Microbiology · 2024Review
- Methanol on the rocks: green rust transformation promotes the oxidation of methane.Journal of the Royal Society, Interface · 2023Article
- Archean phosphorus recycling facilitated by ultraviolet radiation.Proceedings of the National Academy of Sciences of the United States of America · 2023Article
- Linking Methanogenesis in Low-Temperature Hydrothermal Vent Systems to Planetary Spectra: Methane Biosignatures on an Archean-Earth-like Exoplanet.Astrobiology · 2023Article
- Synergies Between Venus & Exoplanetary Observations: Venus and Its Extrasolar Siblings.Space science reviews · 2023Review
- Earliest Photic Zone Niches Probed by Ancestral Microbial Rhodopsins.Molecular biology and evolution · 2022Article
- The case and context for atmospheric methane as an exoplanet biosignature.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
- Timescales for Prebiotic Photochemistry Under Realistic Surface Ultraviolet Conditions.Astrobiology · 2021Article
- Co-evolution of primitive methane-cycling ecosystems and early Earth's atmosphere and climate.Nature communications · 2020Article
- Anomalous fractionation of mercury isotopes in the Late Archean atmosphere.Nature communications · 2020Article
- The Archean atmosphere.Science advances · 2020Review
- Atmospheric COScience advances · 2020Article
- A Review of Possible Planetary Atmospheres in the TRAPPIST-1 System.Space science reviews · 2020Review
- Living at the Extremes: Extremophiles and the Limits of Life in a Planetary Context.Frontiers in microbiology · 2019Review
- Modeling Repeated M Dwarf Flaring at an Earth-like Planet in the Habitable Zone: Atmospheric Effects for an Unmagnetized Planet.Astrobiology · 2019Article
- Transient surface ocean oxygenation recorded in the ∼2.66-Ga Jeerinah Formation, Australia.Proceedings of the National Academy of Sciences of the United States of America · 2018Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
9 authors at 4 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Recognizing whether a planet can support life is a primary goal of future exoplanet spectral characterization missions, but past research on habitability assessment has largely ignored the vastly different conditions that have existed in our planet's long habitable history. This study presents simulations of a habitable yet dramatically different phase of Earth's history, when the atmosphere contained a Titan-like, organic-rich haze. Prior work has claimed a haze-rich Archean Earth (3.8-2.5 billion years ago) would be frozen due to the haze's cooling effects. However, no previous studies have self-consistently taken into account climate, photochemistry, and fractal hazes. Here, we demonstrate using coupled climate-photochemical-microphysical simulations that hazes can cool the planet's surface by about 20 K, but habitable conditions with liquid surface water could be maintained with a relatively thick haze layer (τ ∼ 5 at 200 nm) even with the fainter young Sun. We find that optically thicker hazes are self-limiting due to their self-shielding properties, preventing catastrophic cooling of the planet. Hazes may even enhance planetary habitability through UV shielding, reducing surface UV flux by about 97% compared to a haze-free planet and potentially allowing survival of land-based organisms 2.7-2.6 billion years ago. The broad UV absorption signature produced by this haze may be visible across interstellar distances, allowing characterization of similar hazy exoplanets. The haze in Archean Earth's atmosphere was strongly dependent on biologically produced methane, and we propose that hydrocarbon haze may be a novel type of spectral biosignature on planets with substantial levels of CO
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.