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Related papers: The Cambrian impact hypothesis

200 papers

Planetary obliquity is a first order control on planetary climate and seasonal contrast, which has a number of cascading consequences for life. How moderately high obliquity (obliquities greater than Earth's current obliquity up to…

Earth and Planetary Astrophysics · Physics 2022-08-30 Megan N. Barnett , Stephanie L. Olson

The mean surface temperature on Earth and other planets with atmospheres is determined by the radiative balance between the non-reflected incoming solar radiation and the outgoing long-wave black-body radiation from the atmosphere. The…

Astrophysics · Physics 2009-11-11 Peter D. Ditlevsen

The Early Anthropogenic Hypothesis considers that greenhouse gas concentrations should have declined during the Holocene in absence of humankind activity, leading to glacial inception around the present. It partly relies on the fact that…

Atmospheric and Oceanic Physics · Physics 2011-12-15 Michel Crucifix

Based on cosmological rates, it is probable that at least once in the last Gy the Earth has been irradiated by a gamma-ray burst in our Galaxy from within 2 kpc. Using a two-dimensional atmospheric model we have performed the first…

We propose a model for the Pleistocene Ice Age, assuming the following scenario: Between 3 Myr and 11.5 kyr BP a Mars-sized object existed which moved in a highly eccentric orbit. Originating from this object, gas clouds with a complex…

Geophysics · Physics 2007-05-23 W. Woelfli , W. Baltensperger , R. Nufer

Ice sheets appeared in the northern hemisphere around 3 million years ago and glacial-interglacial cycles have paced Earth's climate since then. Superimposed on these long glacial cycles comes an intricate pattern of millennial and…

Geophysics · Physics 2015-03-19 Michel Crucifix

Gamma-Ray Bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. We have used a two-dimensional atmospheric model to investigate the effects on the Earth's atmosphere of GRBs…

The case for a much warmer climate on the early Earth than now is presented. The oxygen isotope record in sedimentary chert and the compelling case for a near constant isotopic oxygen composition of seawater over geologic time support…

Earth and Planetary Astrophysics · Physics 2015-04-03 David W. Schwartzman

Gamma-ray bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. The gamma radiation from a burst within a few kiloparsecs would quickly deplete much of the Earth's protective ozone…

Earth and Planetary Astrophysics · Physics 2009-08-26 Brian C. Thomas

Recent detections of carbon-bearing molecules in the atmosphere of a candidate Hycean world, K2-18 b, with JWST are opening the prospects for characterising potential biospheres on temperate exoplanets. Hycean worlds are a recently…

Earth and Planetary Astrophysics · Physics 2025-02-13 Emily G. Mitchell , Nikku Madhusudhan

Recent data indicate one or more moderately nearby supernovae in the early Pleistocene, with additional events likely in the Miocene. This has motivated more detailed computations, using new information about the nature of supernovae and…

Earth and Planetary Astrophysics · Physics 2019-06-24 Adrian L. Melott , Brian C. Thomas

In the redshift range 100<(1+z)<137, the cosmic microwave background (CMB) had a temperature of 273-373K (0-100 degrees Celsius), allowing early rocky planets (if any existed) to have liquid water chemistry on their surface and be…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Abraham Loeb

Gamma-ray bursts (hereafter GRB) produce a flux of radiation detectable across the observable Universe, and at least some of them are associated with galaxies. A GRB within our own Ggalaxy could do considerable damage to the Earth's…

Astrophysics · Physics 2009-11-10 A. Melott , B. Lieberman , C. Laird , L. Martin , M. Medvedev , B. Thomas , J. Cannizzo , N. Gehrels , C. Jackman

Immediately after their formation, the terrestrial planets experienced intense impact bombardment by comets, leftover planetesimals from primary accretion, and asteroids. This temporal interval in solar system evolution, termed late…

Earth and Planetary Astrophysics · Physics 2019-08-30 Stephen J. Mojzsis , Ramon Brasser , Nigel M. Kelly , Oleg Abramov , Stephanie C. Werner

The Hadean, once thought to be uninhabitable and tumultuous, has more recently been recontextualized as a clement time in which oceans, land, and life likely appeared on Earth. This non-exhaustive chapter follows multiple threads from…

Earth and Planetary Astrophysics · Physics 2024-11-01 Christopher K Jones , Michaela Leung , Chenyi Tu , Saleheh Ebadirad , Nate Marshall , Lin Tan , Tim Lyons

With the same general purposes as Part I of this monograph, we analyze here major events in the history of the Earth, such as the formation of the Earth itself, the origin of life, the great glaciations and the mass extinctions of species,…

Earth and Planetary Astrophysics · Physics 2025-08-26 Carlos Alberto Olano

An Earth-like planetary magnetic field has been widely invoked as a requirement for habitability as it purportedly mitigates the fluxes of ionizing radiation reaching the surface and the escape of neutrals and ions from the atmosphere.…

Earth and Planetary Astrophysics · Physics 2019-04-12 Manasvi Lingam

It is often presumed, that life evolves relatively fast on planets with clement conditions, at least in its basic forms, and that extended periods of habitability are subsequently needed for the evolution of higher life forms. Many planets…

Earth and Planetary Astrophysics · Physics 2017-11-23 Claudius Gros

Life arose on Earth sometime in the first few hundred million years after the young planet had cooled to the point that it could support water-based organisms on its surface. The early emergence of life on Earth has been taken as evidence…

Earth and Planetary Astrophysics · Physics 2015-03-19 David S. Spiegel , Edwin L. Turner

The Mid-Pleistocene Transition, the shift from 41 kyr to 100 kyr glacial-interglacial cycles that occurred roughly 1 Myr ago, is often considered as a change in internal climate dynamics. Here we revisit the model of Quaternary climate…

Atmospheric and Oceanic Physics · Physics 2019-01-14 Courtney Quinn , Jan Sieber , Anna S. von der Heydt , Timothy M. Lenton