Comets and Asteroids Archives

OSIRIS-REx Sample Return Capsule Re-Entry -- NASA

Comets and Asteroids, Exploration Gear & Tech, Missions & Hardware, Planetary Protection & Biosafety, Sample Return, Status Report

Geophysical Observations Of OSIRIS-REx Sample Return Capsule Re-Entry

by Keith CowingJuly 10, 2024July 7, 2024

Sample Return Capsules (SRCs) entering Earth’s atmosphere at hypervelocity from interplanetary space are a valuable resource for studying meteor phenomena.

Petrology and composition of dark clasts from CR NWA 14250. Back scattered electron (BSE) images from (A) a large chondrule-containing clast and (B) a smaller clast without chondrules.-- Science

Astrochemistry, Astrogeology, Comets and Asteroids, Exoplanets, -moons, -comets, Meteorites & Asteroids, Status Report

The Nucleosynthetic Fingerprint of the Outermost Protoplanetary Disk and Early Solar System Dynamics

by Keith CowingJuly 10, 2024July 7, 2024

Knowledge of the nucleosynthetic isotope composition of the outermost protoplanetary disk is critical to understand the formation and early dynamical evolution of the Solar System.

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 […]

Observed SFDs of C-type asteroid families. The SFDs usually exhibit a steep slope q1 at sizes D ≳ 5 km and a shallow slope q2 at D ≲ 5 km. This break is often created in the course of collisonal evolution. An observational bias affects the SFDs at even smaller sizes (0.5-3 km), depending on the distance and albedo of the respective populations. Additionally, families of P, B and M types were studied (together with 4 of unknown taxonomical classification). -- astro-ph.EP

Astrochemistry, Astrogeology, Comets and Asteroids, Impact events, Meteorites & Asteroids, Status Report

Source Regions of Carbonaceous Meteorites and NEOs

by Keith CowingJuly 3, 2024July 1, 2024

The present work aims to determine the source regions of carbonaceous chondrites (CM, CI, CO, CV, CK, CR, CH, CB, or C-ungrouped). We studied 38 individual asteroid families, including young […]

Shock-fractured quartz grains from (c) Pars-45 quartz grain 09x-12. Composite color (RGB) CL image. Blue represents unmelted quartz; orange represents melted quartz that has been annealed; black represents fractures filled with amorphous silica. Note that the fractures in this grain radiate from the area at the upper right, potentially resulting from a high-pressure collision with another grain. -- ScienceOpen.com

Astrochemistry, Astrogeology, Away Teams & Field Reports, Caves, Craters, Mountains, Subsurface, Lava Tubes, Comets and Asteroids, Fossils & Paleontology, Imaging & Spectroscopy, Impact events, Meteorites & Asteroids, Press Release

Shocked Quartz Reveals Evidence Of Historical Cosmic Airburst During The Younger Dryas

by Keith CowingJune 27, 2024June 27, 2024

Researchers continue to expand the case for the Younger Dryas Impact hypothesis. The idea proposes that a fragmented comet smashed into the Earth’s atmosphere 12,800 years ago, causing a widespread […]

A microscope image of a dark Bennu particle, about a millimeter long, with a crust of bright phosphate. To the right is a smaller fragment that broke off. Credits: From Lauretta & Connolly et al. (2024) Meteoritics & Planetary Science, doi:10.1111/maps.14227.

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Missions & Hardware, Press Release, Sample Return

An OSIRIS-REx Asteroid Sample Has Surprising Phosphate Content

by Keith CowingJune 27, 2024June 27, 2024

Scientists have eagerly awaited the opportunity to dig into the 4.3-ounce (121.6-gram) pristine asteroid Bennu sample collected by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security – Regolith Explorer) […]

An artist’s rendition of Saturn’s moon Enceladus depicts hydrothermal activity on the seafloor and cracks in the moon’s icy crust that allow material from the watery interior to be ejected into space. New research shows that instruments destined for the next missions could find traces of a single cell in a single ice grain contained in a plume. NASA/JPL-Caltech

Analog Studies, Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Comets and Asteroids, Enceladus, Europa, Extremeophiles and Extreme Environments, Icy Worlds, Imaging & Spectroscopy, Meteorites & Asteroids, Missions & Hardware, Status Report, Water/Hycean Worlds & Oceanography

Laboratory Characterization Of Hydrothermally Processed Oligopeptides In Ice Grains Emitted By Enceladus And Europa

by Keith CowingJune 25, 2024June 25, 2024

The Cassini mission provided evidence for a global subsurface ocean and ongoing hydrothermal activity on Enceladus, based on results from Cassini’s mass spectrometers. Laboratory simulations of hydrothermal conditions on icy […]

Ratio of the cumulative collision rate of comets with the Earth analog to the cumulative collision rate of carbonaceous asteroids with the Earth analog. The cumulative collision rates are reset at the time of the Moon-forming impact; and the ratio is set to 0 when the cumulative collision rates of carbonaceous asteroids (denominator) equals 0. So the dashed line shows the number of collisions with comets relative to the number of collisions with carbonaceous asteroids (weighted by their respective numbers in our simulations) on Earth since gas disk dispersal until the Moon-forming impact; and the solid line shows the same relative number since the Moon-forming impact until the end of the simulation. While cumulative collision rates of comets with Earth are ≃ 4 orders of magnitude smaller than those of carbonaceous asteroids before the Moon-forming impact, they are between 3 and 7 orders of magnitude smaller after the Moon-forming impact. In 30% of our simulations, there is about 1 comet every 103 carbonaceous asteroids colliding with the Earth after the Moon-forming event, which is consistent with the total cometary mass expected during late accretion. -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Extinction events, Gaia - Planetary Perspectives, Habitable Zones, Impact events, Meteorites & Asteroids, Moon, Origin & Evolution of Life, Status Report, Water/Hycean Worlds & Oceanography

Crash Chronicles: Relative Contribution From Comets and Carbonaceous Asteroids to Earth’s Volatile Budget In The Context of an Early Instability

by Keith CowingJune 25, 2024June 25, 2024

Recent models of solar system formation suggest that a dynamical instability among the giant planets happened within the first 100 Myr after disk dispersal, perhaps before the Moon-forming impact. As […]

Top panel: FC2 spectral endmember O (organic-rich), B (global Ceres background), and S (shade), respectively. Bottom panel: RGB map where the abundance of the endmember O is represented in red, the endmember B in green, and the S in blue. The pixel scale of this mosaic is ~136 m/pixel and the images were acquired with a phase value of ~50. Ernutet is the central crater (pointed by the yellow arrow) of the scene in which the organics are visible. -- astro-ph.EP

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Ceres, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Press Release

New Candidates for Organic-rich Regions on Ceres

by Keith CowingJune 24, 2024June 24, 2024

We explore the spatial distribution of organics on Ceres using the visible and near-infrared data collected by the Dawn mission.

Optical image of the clastic matrix region in LAR 12252 that was studied using S-XANES. Notable phases include enstatite (example outlined in red), sulphides (example outlined in yellow), a small chondrule fragment (outlined in orange), and fine matrix (example highlighted in pink). b Corresponding map calculated from the SXANES spectra of the region shown in a, showing the amplitude of the H-S peak at each point normalised to the average amplitude of point spectra measured from chondrule mesostasis. Black pixels correspond to points where the S-XANES spectra that did not contain a resolvable H-S peak. White pixels correspond to points where the SXANES spectra could not be fitted due to their quality or noise in the spectra. -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Meteorites & Asteroids, Status Report, Water/Hycean Worlds & Oceanography

The Source of Hydrogen in Earth’s Building Blocks

by Keith CowingJune 21, 2024June 21, 2024

Despite being pivotal to the habitability of our planet, the process by which Earth gained its present-day hydrogen budget is unclear. Due to their isotopic similarity to terrestrial rocks across […]

Comets and Asteroids

Geophysical Observations Of OSIRIS-REx Sample Return Capsule Re-Entry

The Nucleosynthetic Fingerprint of the Outermost Protoplanetary Disk and Early Solar System Dynamics

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

Source Regions of Carbonaceous Meteorites and NEOs

Shocked Quartz Reveals Evidence Of Historical Cosmic Airburst During The Younger Dryas

An OSIRIS-REx Asteroid Sample Has Surprising Phosphate Content

Laboratory Characterization Of Hydrothermally Processed Oligopeptides In Ice Grains Emitted By Enceladus And Europa

Crash Chronicles: Relative Contribution From Comets and Carbonaceous Asteroids to Earth’s Volatile Budget In The Context of an Early Instability

New Candidates for Organic-rich Regions on Ceres

The Source of Hydrogen in Earth’s Building Blocks

Potential Survivable Niches For Microbial Life On The Lunar South Pole

JWST Telemetry Combined With Active Coronagraphy: Raw Contrast Predictions For Exoplanet Imaging With The Habitable Worlds Observatory

Antarctica Is Home To Microbes Found Nowhere Else On Earth

Study: Peptides Can Form Well-defined Structures In Harsh, Venus-like Conditions

Modeling Carbon-Based Planets with MAGRATHEA