November 2024 – Page 2 – My WordPress Site

Full-cadence dynamic spectra for the two false-positive events found in the reduced Choza et al. (2024) data set, with time from the beginning of the observation on the y-axis and frequency offset from the starting frequency of the event on the x-axis. Each block in a stack is one of the six pointings that make up the ABACAD observing cadence. The event from the DDO 210 observation was also found by Choza et al. (2024), while the event from the NGC 628 observation is new. -- astro-ph.IM

Astronomy & Telescopes, Intelligence & Language, Interstellar, Magnetic Fields, Electromagnetism, bioelectricity,, SETI & Technosignatures

Anomaly Detection and RFI Classification with Unsupervised Learning in Narrowband Radio Technosignature Searches

by Keith CowingNovember 29, 2024November 29, 2024

Summary of ISO stream morphologic properties. The top four panels compare the width, height, length, and peak density of a set of simulated streams to rules of thumb for each of these quantities. In the bottom row, the velocity dispersion along the 3 different axes of the stream is compared to the initial velocity dispersion σ0. The bottom right panel shows the shape parameters of the density distribution. In each panel, 5 points are shown for each stream, corresponding to 5 randomly-selected times between 0 and 10 Gyr. For the most part we expect streams to follow the 1:1 line shown in these panels, and for the most part they do, over 3+ orders of magnitude. The exception is σL, the velocity dispersion along the stream direction, which is typically far less than σ0, since a particle’s position in the stream is primarily determined by its velocity in this direction. Note that for plotting clarity we have included a small random scatter of 0.07 dex on the x-coordinates of points where the x-axis is σ0 times a constant, since many points have identical values. -- astro-ph.EP

Comets and Asteroids, Panspermia

He Awa Whiria: The Tidal Streams of Interstellar Objects

by Keith CowingNovember 28, 2024November 28, 2024

The deuterium/hydrogen (D/H) ratio in astronomical objects and on Earth. A technosignature in exoplanetary water of prolonged deuteriumdeuterium nuclear fusion would plot below natural astronomical D/H values in the green shaded zone and be anomalous. Data sources: Bocklee-Morvan et al. (2015) and references therein for comets; Donahue et al. (1997) for Venus; Mahaffy et al. (2015) for Mars; Table S2 of Alexander et al.(2012) -- astro-ph.EP

Astronomy & Telescopes, Biosignatures & Paleobiology, Imaging & Spectroscopy, SETI & Technosignatures

Potential Technosignature From Anomalously Low Deuterium/Hydrogen (D/H) In Planetary Water Depleted by Nuclear Fusion Technology

by Keith CowingNovember 28, 2024November 28, 2024

Cross-correlation SNRs as a function of systemic velocity (Vsys) and Keplerian velocity (Kp) for H2O, CH4, CO2, and CO from the four nights combined. We detect H2O at an SNR of 3.51 but do not detect any carbon-bearing species, although CO may be a tenative detection. The white dashed lines represent the Vsys and Kp values of WASP-43b from the literature (Gaia Collaboration et al. 2018; Bonomo et al. 2017). The red x’s indicate the maximum signal from the literature (Gaia Collaboration et al. 2018; Bonomo et al. 2017). The red x’s indicate the maximum signal from the cross-correlation. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Water/Hycean Worlds & Oceanography

A Measurement of the Water Abundance in the Atmosphere of the Hot Jupiter WASP-43b with High-resolution Cross-correlation Spectroscopy

by Keith CowingNovember 28, 2024November 28, 2024

Mass versus radius diagram of observed and synthetic planets. The four panels show the resulting planets using different model variations contrasted against the observational data from Parc et al. (2024). The synthetic data for all models is sampled according to the stellar mass distribution of the observations and an estimate of the detection and transit probability is applied. More saturated dots imply that the planet was sampled multiple times due to being more likely to be detected and their color is given by the planets’ water mass fraction. -- astro-ph.EP

Astrogeology, Exoplanets, -moons, -comets, Ice Giant, Icy Worlds

Water-rich sub-Neptunes and Rocky Super Earths Around Different Stars: Radii Shaped by Volatile Partitioning, Formation, and Evolution

by Keith CowingNovember 28, 2024May 12, 2025

Spaceline Current Awareness

Microgravity, Space Life Science, Space Physiology & Medicine, Space Stations, SPACELINE Current Awareness List

NASA Spaceline Current Awareness List #1,125 22 November 2024 (Space Life Science Research Results)

by Keith CowingNovember 27, 2024November 27, 2024

Larger image

Biosignatures & Paleobiology, Cryobiology, Europa, Habitable Zones, Icy Worlds, Jupiter, Missions & Hardware

Astrobiology Explorer Europa Clipper’s Trajectory To Jupiter

by Keith CowingNovember 27, 2024November 27, 2024

a, Working model of rereading. b, Top box shows example trace of PASTOR-reread showing three almost-complete reread events (blue trace). Our model’s predicted signal for the PASTOR-reread sequence (pink trace) was aligned to each reread. The fourth VR contains an asparagine mutation, but the corresponding signal level consistently resembles aspartate in all three instances of this PASTOR-reread trace. The modelled sequence was changed to contain an aspartate to reflect the putative PTM. Bottom box shows the approximate region of the strand that is in the nanopore over time. -- Nature

Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Exploration Gear & Tech, Genomics, Proteomics, Bioinformatics, Nanotechnology & SynBio, Tricorders & Sensors

Tricorder Tech: Multi-pass, Single-molecule Nanopore Reading of Long Protein Strands

by Keith CowingNovember 27, 2024November 27, 2024

Graphical Abstract: self-replication: When sulfur is positioned between the two nitrogens of benzothiadiazole, it can engage in edge-on molecular recognition events. We present a new potential self-replicating system based on this interaction, and evidence for autocatalysis. The designs have implications for exobiology, due to their cosmic similarities and potential for genetic capacity. -- Chemistry A European Journal

Astrochemistry, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Imaging & Spectroscopy, Interstellar, Origin & Evolution of Life

Self‐Replication Without Hydrogen‐Bonds: An Exobiotic Design

by Keith CowingNovember 27, 2024November 27, 2024

Radiative cooling rate per molecule under optically thin and LTE conditions as a function of temperature. The upper panel shows the cooling rates of C-bearing species, while the lower panel displays those of H- and O-bearing species, respectively. The net radiative cooling rate of each species is calculated by summing the cooling rate for each energy transition (Equation (12) in Supplementary Information), with reference to line data provided by HITRAN and ExoMol database. -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Water/Hycean Worlds & Oceanography

Suppression of Hydrodynamic Escape of an H2-rich Early Earth Atmosphere by Radiative Cooling of Carbon Oxides

by Keith CowingNovember 27, 2024September 18, 2025