astrogeology Archives

The first public display of a sample from asteroid Bennu Credit: (NASA/Keegan Barber)

Astrochemistry, Astrogeology, Comets and Asteroids, Meteorites & Asteroids, Missions & Hardware, Press Release

National Museum of Natural History Unveils Display of Asteroid Bennu Sample

by Keith CowingNovember 3, 2023

The first public display of a sample from asteroid Bennu is seen, Friday, Nov. 3, 2023, at the Smithsonian’s National Museum of Natural History in Washington.

The pebble surface density for scenario 1 (top) and scenario 2 (bottom) is depicted for different α-viscosities, dependent on disk radius and time. In each case, the red vertical line denotes the water-ice line, and the green line marks the position of the gas giant, if present. In the scenario with a gas giant, the accumulation of blocked pebbles exterior to the gas giant’s position is visible. Further accumulations within the water-ice line result from the recondensation of outwardly diffusing gas at different evaporation lines. -- astro-ph.EP

Astrochemistry, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Status Report, Water/Hycean Worlds & Oceanography

Constraining The Formation History Of The HAT-P-11 System By Atmospheric Abundances

by Keith CowingOctober 23, 2023October 20, 2023

The chemical fingerprint of a planet reveals information about its formation history regarding when and where it formed. The water content of a planet can help to constrain its formation […]

Diagram of ε46Ti vs. ε50Ti for CB, CH and CR chondrite samples investigated in the present study. Bulk CR data for Acfer 139 (dark blue square) and NWA 801(gray square) are from this study and from Zhang et al. (2012), respectively. Literature data for different carbonaceous chondrite groups are stated as composite points averaging multiple samples within each group and are shown for comparison (white squares). The weighted ε50Ti– ε46Ti regression (solid black line) and related error envelopes were calculated using Isoplot, and include bulk meteorite data available from previous works. All reported uncertainties reflect 95% confidence intervals (95% CI). Literature data were taken from the recent compilation of Burkhardt et al. (2019) and references therein. -- astro-ph.EP

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Status Report

Age And Genetic Relationships Among CB, CH and CR Chondrites

by Keith CowingOctober 23, 2023October 20, 2023

The carbonaceous Bencubbin-like (CB), high-metal (CH), and Renazzo-like (CR) chondrites are metal-rich chondrites that have been suggested to be genetically linked and are sometimes grouped together as the CR chondrite […]

Mercury, Press Release

The Origin Of Mercury’s Structure and Chemical Composition and Their Astrobiological Implications

by Keith CowingOctober 17, 2023October 17, 2023

Mercury can be categorized as either an endmember or an outlier planet due to its unusually large iron core, constituting approximately 70% of its total mass. The origin of this […]

‘Oumuamua -- Illustration by Samuel Cabot

Astrochemistry, Astrogeology, Astronomy & Telescopes, Comets and Asteroids, Interstellar, Meteorites & Asteroids, Panspermia, Press Release, Space Weather & Heliophysics

X-rays May Tell Us More About The Origins Of Visiting Space Rocks

by Keith CowingOctober 14, 2023October 14, 2023

A research team led by a Yale astronomer has some advice for our next close encounter with a wandering, interstellar object. Check its X-rays on the way out. Since 2017, […]

Schematic illustration of transport and mixing between different isotopic reservoirs during growth of Mars and Earth. Mars was born near the inner edge of the main asteroid belt, in between the ℰ and � reservoirs. It started accreted an equal mixture of both planetesimals (A) but progressively accreted more ℰ material as it migrated inwards into the ℰ region by type I migration (B). During those times, carbonaceous asteroids from the outer solar system were scattered inwards by the giant planets, but interaction with nebular gas led to their implantation into the outer main belt. Larger carbonaceous objects were less subjected to gas drag and were able to penetrate in the inner solar system. Earth grew later primarily from ℰ -type embryos (C). Several tens of millions of years after solar system formation, one or several interloper carbonaceous embryos implanted in the inner disk during the first phase were stochastically accreted by the Earth (D). -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Mars, Status Report

Bayesian Inference On The Isotopic Building Blocks Of Mars And Earth

by Keith CowingSeptember 30, 2023September 30, 2023

Isotopic anomalies provide a means of probing the materials responsible for the formation of terrestrial planets. By analyzing new iron isotopic anomaly data from Martian meteorites and drawing insights from […]

The sample return capsule from NASA’s OSIRIS-REx mission is seen shortly after touching down in the desert, Sunday, Sept. 24, 2023, at the Department of Defense's Utah Test and Training Range.

Astrochemistry, Astrogeology, Away Teams & Field Reports, Biosignatures & Paleobiology, Comets and Asteroids, Missions & Hardware, Planetary Protection & Biosafety, Press Release

The OSIRIS-REx Samples From Bennu Have Landed On Earth

by Keith CowingSeptember 25, 2023September 25, 2023

After years of anticipation and hard work by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification and Security – Regolith Explorer) team, a capsule of rocks and dust collected from asteroid […]

Abundance profiles for selected condensates. Left panel: iron-bearing condensates, middle panel: magnesium and calcium species, right panel: Na and K condensates. The solid lines refer to the equilibrium condensation calculations. Dashed lines indicate the results for the rainout approximation. -- astro-ph.EP

Astrochemistry, Astrogeology, Brown Dwarfs, Exoplanets, -moons, -comets, Status Report

FastChem Cond: Equilibrium Chemistry with Condensation and Rainout for Cool Planetary and Stellar Environments

by Keith CowingSeptember 6, 2023September 6, 2023

Cool astrophysical objects, such as (exo)planets, brown dwarfs, or asymptotic giant branch stars, can be strongly affected by condensation. Condensation does not only directly affect the chemical composition of the […]

A training model of the sample return capsule is seen is seen during a drop test in preparation for the retrieval of the sample return capsule from NASA's OSIRIS-REx mission, Wednesday, Aug. 30, 2023 -- NASA

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Missions & Hardware, Planetary Protection & Biosafety, Press Release

NASA Completes Last OSIRIS-REx Test Before Asteroid Sample Delivery

by Keith CowingSeptember 5, 2023September 5, 2023

A team led by NASA in Utah’s West Desert is in the final stages of preparing for the arrival of the first U.S. asteroid sample – slated to land on […]

Fraction of different types of planets formed around stars in a grid with varying [Fe/H] and M∗. In order to form giant planets and super-Earths we require either a high metallicity or a high stellar mass. Further, water-rich planets are more common around stars with higher metallicities and stellar mass as these stars can sustain a high enough pebble flux outside the water ice line to form water-rich planets there. Earth-mass planets dominate for all metallicities and stellar masses as they do not require a high pebble flux in order to form. -- astro-ph.EP

Astrochemistry, Astrogeology, Exoplanets, -moons, -comets, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

Planet Formation Throughout The Milky Way: Planet Populations In The Context Of Galactic Chemical Evolution

by Keith CowingSeptember 1, 2023September 1, 2023

As stellar compositions evolve over time in the Milky Way, so will the resulting planet populations. In order to place planet formation in the context of Galactic chemical evolution, we […]