Comets and Asteroids Archives

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Conferences and Meetings, Meteorites & Asteroids, Missions & Hardware, Planetary Protection & Biosafety, Sample Return, Status Report

Extraterrestrial Materials Analysis Group (ExMAG) Spring 2024 Meeting

by Keith CowingApril 25, 2024April 25, 2024

May 13–15, 2024Houston, Texas/Virtual

Final distributions of planets at 𝑡 = 200 Myr, in four sets of simulations with different instability times. The timing of the instability is indicated at the top of each panel, relative to the time of the gas disk dispersal. Each panel shows the results of simulations considering rings with different radial surface density profiles. The x-axis shows planets’s semi-major axis. The y-axis shows the planets’ mass. Light-grey dots show planets produced in our simulations. The four dark-grey dots represent the real terrestrial planets. The giant planet dynamical instability is mimicked by assuming that Jupiter and Saturn instantaneously jump from their pre-instability orbits to their current ones at 𝑡 = 𝑡 inst.-- astro-ph.EP

Astrogeology, Comets and Asteroids, Meteorites & Asteroids, Status Report

Implantation Of Asteroids From The Terrestrial Planet Region: The Effect Of The Timing Of The Giant Planet Instability

by Keith CowingApril 24, 2024April 24, 2024

The dynamical architecture and compositional diversity of the asteroid belt strongly constrain planet formation models.

CREDIT ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA; J. Roger – CC BY SA 4.0 Larger image

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Missions & Hardware, Status Report, Tricorders & Sensors

A Cometary Landcape Covered With Organic Chemicals

by Keith CowingApril 23, 2024June 8, 2024

Editor’s note: according to “Organic compounds on comet 67P/Churyumov-Gerasimenko revealed by COSAC mass spectrometry” – “Comets harbor the most pristine material in our solar system in the form of ice, […]

Aqueous chemistry inside meteorite parent bodies allows the formation of prebiotic molecules crucial for all life in the early solar system. We present a reaction mechanism suitable for vitamin B3 synthesis in this environment, which is experimentally verified in the literature. Vitamin B3 was transported to the Hadean Earth by meteorite falls and initiated redox chemistry in the form of NAD(P)H, potentially participating in the origins of life. -- ChemPlusChem

Astrochemistry, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Interstellar, Meteorites & Asteroids, Origin & Evolution of Life, Status Report

Prebiotic Vitamin B3 Synthesis in Carbonaceous Planetesimals

by Keith CowingApril 23, 2024April 23, 2024

Aqueous chemistry within carbonaceous planetesimals is promising for synthesizing prebiotic organic matter essential to all life. Meteorites derived from these planetesimals delivered these life building blocks to the early Earth, […]

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, and the inside of the canister’s lid. -- astro-ph.EP

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Exploration Gear & Tech, Meteorites & Asteroids, Missions & Hardware, Sample Return, Status Report

Asteroid (101955) Bennu In The Laboratory: Properties Of The Sample Collected By OSIRIS-REx

by Keith CowingApril 22, 2024April 22, 2024

On 24 September 2023, the NASA OSIRIS-REx mission dropped a capsule to Earth containing approximately 120 g of pristine carbonaceous regolith from Bennu.

Secondary electron (SE) SEM images of a CI (a and c) and CM (b and d) simulant pellet before and after irradiation. Panels a and b show images of the fresh material, while panels c and d are of representative laser-irradiated regions. The white scale bar at the lower left side of each panel corresponds to 2 𝜇𝑚 in length. -- astro-ph.EP

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Space Weather & Heliophysics, Status Report

Laser Irradiation of Carbonaceous Chondrite Simulants: Space Weathering Implications for C-complex Asteroids

by Keith CowingApril 19, 2024

Surfaces of carbonaceous asteroids (C-complex) have shown diverse contrasting spectral variations, which may be related to space weathering.

Schematic diagram of our preferred scenario. Red circles are planetesimals (and their fragments) from the terrestrial planet region. The black solid curves roughly denote the boundary of the current asteroid inner main belt. Eccentricity increases from bottom to top. Each panel shows the proposed evolution of the inner Solar System at different time ranges: (A) Formation and cooling of the EL planetesimal in the terrestrial planet region before 60 Myr after Solar System formation. In this period, the terrestrial planets began scattering planetesimals to orbits with high eccentricity and semimajor axes that correspond to the asteroid main belt. (B) Between 60 and 100 Myr, the EL planetesimal was destroyed by an impact in the terrestrial planet region. At least one fragment (the Athor family progenitor) was scattered by the terrestrial planets into the scattered disk, as in (A), then the giant planet instability implanted it into the inner main belt by decreasing its eccentricity. (C) A few tens of millions of years after the giant planet instability occurred, a giant impact between the planetary embryo Theia and proto-Earth formed the Moon. (D) The Athor family progenitor experienced another impact event that formed the Athor family at ~1500 Myr. -- Science

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Gas Giants, Meteorites & Asteroids, Press Release

Dating The Solar System’s Giant Planet Migration Using Chondrite Meteorites

by Keith CowingApril 16, 2024April 16, 2024

The period of orbital instability that led to the migration of the Solar System’s giant planets to their current orbit occurred between 60 and 100 million years after the beginning […]

Map of the north polar region of Ceres. The color areas are areas that are continuously shadowed over a Ceres year, and therefore very cold. The axis tilt (obliquity) of Ceres slowly changes over time and is currently 4 degrees, but ranged between 2 and 20 degrees over time. The color indicates the maximum obliquity at which a location is in shadow through an entire orbit. Credit: Erwan Mazarico/GSFC.

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Press Release

History Of Ceres’s Young Cold Traps

by Keith CowingApril 16, 2024April 16, 2024

Ceres, the largest asteroid in our Solar System, harbors a dark secret: Extremely young ice deposits in permanently shadowed craters near its poles. If that sounds vaguely familiar, it’s because […]

Schematic of the VENUS setup viewed from above, showing a multi-beam stage with five beam lines (Left, Top, Central, Bottom, and Right beams) for material injection, symmetrically distributed around the central port. The CB and BB are vertically aligned below the TB. Each beam is equipped with a set of diaphragms to collimate the particle stream into the vacuum chambers CH1 and CH2 at pressures of 10−8 hPa and 10−9 hPa, respectively. The main chamber (10−10 hPa) houses a gold-plated target for growing the ice samples. Gas-phase species are monitored by a QMS that is placed in front of the sample during TPD analysis. A cryocooler and thermal shield regulate the system’s temperature. -- astro-ph.GA

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Comets and Asteroids, Interstellar, Status Report

Comprehensive Laboratory Constraints On Thermal Desorption Of Interstellar Ice Analogues

by Keith CowingApril 3, 2024April 3, 2024

To explain grain growth and destruction in warm media, ice mantle formation and sublimation in cold media, and gas line emission spectroscopy, astrochemical models must mimic the gas–solid abundance ratio. […]

A top-down view of one of the containers holding rocks and dust from asteroid Bennu, with hardware scale marked in centimeters. Erika Blumenfeld, creative lead for the Advanced Imaging and Visualization of Astromaterials (AIVA) and Joe Aebersold, AIVA project management lead, captured this picture using manual high-resolution precision photography and a semi-automated focus stacking procedure. The result is a sample image that can be zoomed in on to show extreme detail. Credit: NASA/Erika Blumenfeld and Joseph Aebersold Larger image

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

OSIRIS-REx Asteroid Samples Now Available to World’s Scientists

by Keith CowingApril 1, 2024April 1, 2024

Scientists outside of NASA’s OSIRIS-REx team are getting their first close look at the asteroid Bennu samples available for independent research just six months after their delivery to Earth.

Comets and Asteroids

Extraterrestrial Materials Analysis Group (ExMAG) Spring 2024 Meeting

Implantation Of Asteroids From The Terrestrial Planet Region: The Effect Of The Timing Of The Giant Planet Instability

A Cometary Landcape Covered With Organic Chemicals

Prebiotic Vitamin B3 Synthesis in Carbonaceous Planetesimals

Asteroid (101955) Bennu In The Laboratory: Properties Of The Sample Collected By OSIRIS-REx

Laser Irradiation of Carbonaceous Chondrite Simulants: Space Weathering Implications for C-complex Asteroids

Dating The Solar System’s Giant Planet Migration Using Chondrite Meteorites

History Of Ceres’s Young Cold Traps

Comprehensive Laboratory Constraints On Thermal Desorption Of Interstellar Ice Analogues

OSIRIS-REx Asteroid Samples Now Available to World’s Scientists

Rethinking The Origin Of Life At Seafloor Hydrothermal Vents

Proto-Biosignatures and Planetary Geochemical Metabolism: A Thermodynamic Screening Model of Prebiotic Geochemical Organization

Cultivation Of Halophilic Archaea In Shallow Subsurface Martian Conditions Has Implications For Extant Life On Mars

Roman Space Telescope Leaves Earth

Atmospheric Retrieval of Combined JWST, HST, and Ground-Based Observations Reveals a Featureless Transmission Spectrum for GJ 1132 b