astrogeology Archives

Porous chondrite dust particle, Wikipedia

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Interstellar, Panspermia, Status Report

The Possibility Of Panspermia In The Deep Cosmos By Means Of The Planetary Dust Grains

by Keith CowingFebruary 9, 2024February 9, 2024

By obtaining the assumption that planetary dust particles can escape from the gravitational attraction of a planet, we consider the possibility for the dust grains to leave the star’s system […]

JWST/NIRSpec integrated spectra and 1σ uncertainties (gray error bars) of Callisto’s leading (purple) and trailing (red) hemisphere, normalized to 1 at 3.82 μm and offset vertically for clarity. The G395H grating has a ~0.1 μm wide wavelength gap, shifting between ~4 and 4.2 μm across NIRSpec IFU’s 29 image slices. Some of the image slices that span Callisto’s disk include wavelength coverage between ~4 and 4.2 μm, which are shown here for Callisto’s leading (bright blue) and trailing (bright orange) hemispheres. All spectral features identified in this study are labeled, with dotted lines indicating their central wavelengths. Features with confirmed compositions have bolded labels, whereas weak features, or those with multiple compositional interpretations, are italicized and followed by question marks. Possible bands and spectral structure at wavelength >4.98 μm may result from data calibration artifacts and are not analyzed in this study. The inset box shows a close-up of the 4.19 to 4.42 μm wavelength range, highlighting the CO2 features we have identified and the different band centers for 12CO2 on Callisto’s leading (4.254 μm) and trailing (4.250 μm) hemisphere, as well as a feature near 4.3 μm that may result from an isotope of CO2 or could be a residual solar line (Appendix A.3). -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Callisto, Icy Worlds, Imaging & Spectroscopy, Jupiter, Status Report

Revealing Callisto’s Carbon-rich Surface And CO2 Atmosphere With JWST

by Keith CowingJanuary 31, 2024January 31, 2024

We analyzed spectral cubes of Callisto’s leading and trailing hemispheres, collected with the NIRSpec Integrated Field Unit (G395H) on the James Webb Space Telescope.

Using a nanomanipulator and an ultra-fine ion beam, a tiny lamella, about five by ten micrometres in size and only one hundred nanometres thin, is cut out of the meteorite and attached to a sample bar. The scientists can then analyze the organic particles in this lamella under an electron microscope (right). CREDIT SuperSTEM Laboratory, Daresbury, UK

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Imaging & Spectroscopy, Impact events, Meteorites & Asteroids, Press Release

Cosmic Building Blocks Of Life Discovered Through An Electron Microscope

by Keith CowingJanuary 30, 2024January 30, 2024

Meteorites are fragments of asteroids which find their way to Earth as shooting stars. These cosmic sediments have frozen the primordial soup from which our solar system emerged – preserving […]

Partial pressures of most abundant species in the vapor calculated using the Equilibrium method (left plot, same as Fig B.3 from Charnoz et al. (2023)) and the Sum method (right plot, methodology of Zilinskas et al. (2023); Piette et al. (2023)), for different monoatomic hydrogen pressure P0 H when the atmosphere is at equilibrium with the magma ocean at T = 3000 K and hydrogen is not in equilibrium with the magma ocean. -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Lava / magma ocean / Volcanic Worlds, Status Report

Hydrogenated Atmospheres Of Lava Planets: Atmospheric Structure And Emission Spectra

by Keith CowingJanuary 29, 2024May 11, 2024

Hot rocky super-Earths are thought to be sufficiently irradiated by their host star to melt their surface and thus allow for long-lasting magma oceans.

A melt splash discovered on a Ryugu sample surface. The melt splash shows a round shape. - Tohoku University

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Impact events, Press Release

Records Of Cometary Dust Hitting Asteroid Ryugu

by Keith CowingJanuary 24, 2024January 23, 2024

Ryugu is a near-Earth asteroid that gained significant attention when the Japanese Hayabusa2 mission collected samples and returned them to Earth. These samples have proven to offer a treasure trove […]

A top-down view of the OSIRIS-REx Touch-and-Go-Sample-Acquisition-Mechanism (TAGSAM) head with the lid removed, revealing the remainder of the asteroid sample inside. -- NASA

Astrochemistry, Astrogeology, Comets and Asteroids, Missions & Hardware, Status Report

Sample Return Update: OSIRIS-REx Asteroid Sample Revealed

by Keith CowingJanuary 22, 2024January 22, 2024

Erika Blumenfeld, creative lead for the Advanced Imaging and Visualization of Astromaterials (AIVA) and Joe Aebersold, project management lead, captured this picture using manual high-resolution precision photography and a semi-automated […]

Principal component values for all six meteorites studied at different grain sizes are shown with the “α-line” boundary from DeMeo et al. (2009) that separates the S- and C/X-complexes. Grain size variations can be seen by using the dotted line interconnecting PC values of measurements of the same meteorite at different grain sizes. Marker size increases with grain size which includes values of 45-90 µm, 90-150 µm, 150-300 µm, 300-500 µm, and 500-1,000 µm. The Lunar-style space weathering trend from Binzel et al. (2019) is shown with blue dots and a corresponding arrow showing the direction of increasing space weathering. The carbonaceous space weathering trend from Lantz et al. (2018) is shown with the brown arrow indicating that the measured weathering trend would move in either direction depending on the meteorite composition. It also shows that differentiating between space weathering and grain size effects would be challenging in PC space. -- astro-ph.EP

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

Grain Size Effects on UV-MIR (0.2-14 micron) Spectra of Carbonaceous Chondrite Groups

by Keith CowingJanuary 22, 2024January 22, 2024

Carbonaceous chondrites are among the most important meteorite types and have played a vital role in deciphering the origin and evolution of our solar system.

Comparison of spectral variation trends in the 3 μm bands of CCs and asteroids. Asteroids are grouped based on the SMASSII taxonomy into C-complex (carbonaceous, including C, B, Cb, Cg, Cgh, and D types), S-complex (silicate, including S, A, R, K, L, Sa, Sq, Sr, Sk, Sl, and V types), and X-complex (metal-rich, including X, Xe, Xk, Xc types, corresponding to the M, P, E types in Tholen taxonomy, which lack absorption features and exhibiting high reflectance). -- astro-ph.EP

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

Near-mid Infrared Spectroscopy Of Carbonaceous Chondrites: Insights Into Spectral Variation Due To Aqueous Alteration And Thermal Metamorphism In Asteroids

by Keith CowingJanuary 18, 2024January 18, 2024

Carbonaceous chondrites (CCs) are windows into the early Solar system and the histories of their parent bodies. Their infrared spectral signatures are powerful proxies for deciphering their composition and evolution […]

Optical spectrum of Comet 46P/Wirtanen observed on 2018-12-13 using the LISA spectrograph. -- astro-ph.EP

Astrochemistry, Astrogeology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Status Report

Long-term Spectroscopic Monitoring Of Comet 46P/Wirtanen

by Keith CowingJanuary 14, 2024January 14, 2024

Jupiter Family Comets (JFCs), having orbital period less than 20 years, provide us with an opportunity to observe their activity and analyse the homogeneity in their coma composition over multiple […]

Interstellar Mapping and Acceleration Probe -- NASA

Astrochemistry, Astrogeology, Intelligence & Language, Missions & Hardware, Press Release

Interstellar Mapping and Acceleration Probe Will Capture Interstellar Stardust

by Keith CowingJanuary 13, 2024January 13, 2024

Scientists and engineers at the CU Boulder will soon take part in an effort to collect a bit of stardust—the tiny bits of matter that flow through the Milky Way […]