Oort Cloud comet Archives

Upper. Detections of H2O, HCN, C2H2, and OH∗ in E3 covering iSHELL echelle order 170–172. The uppermost trace is the observed cometary spectrum with the telluric transmittance model superimposed. Below are individual molecular fluorescence models color-coded by species. The bottom trace shows the residual (cometary spectrum minus all models) with the 1σ uncertainty envelope overlaid and shaded. Lower. Zoomed plots covering the gray shaded regions indicated in the upper panel. In this case, the uppermost trace is the telluric-subtracted comet spectrum, with individual fluorescence models plotted below. We searched for NH2, a potentially confounding species in this spectral region, but did not detect it. Our 3σ upper limit is NH2/H2O < 0.03%. -- astro-ph.EP

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

Coma Volatile Composition And Thermal Physics In Comet C/2022 E3 (ZTF) Measured Near Closest Approach To Earth With NASA-IRTF

by Keith CowingFebruary 11, 2026February 11, 2026

The 2023 perihelion passage of comet C/2022 E3 (ZTF) afforded an opportunity to measure the abundances and spatial distributions of coma volatiles in an Oort cloud comet at high spatial […]

3I spectrum (dots) and the reflectance spectra of three CR and one R chondrite discussed in the text. -- astro-ph.EP

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Interstellar, Status Report

Spectrophotometric Evidence For A Metal-bearing, Carbonaceous, and Pristine Interstellar Comet 3I/ATLAS

by Keith CowingNovember 30, 2025November 30, 2025

3I/ATLAS is only the second confirmed cometary object known to enter the Solar System from interstellar space.

Oort Cloud comet

Coma Volatile Composition And Thermal Physics In Comet C/2022 E3 (ZTF) Measured Near Closest Approach To Earth With NASA-IRTF

Spectrophotometric Evidence For A Metal-bearing, Carbonaceous, and Pristine Interstellar Comet 3I/ATLAS

ALMA Central Molecular Zone Exploration Survey (ACES) I: Overview

RNA And Proteins Joined Up At The Origins Of Life: Persistence Is The Point

Selection For Growth Drives The Emergence Of Genetic Heredity In Protocells

NASA SMD ROSES-25 Amendment 65: New Opportunity: C.4 Planetary Science Enabling Facilities

TESS Photometry and Radial Velocity Analysis of the sub-Neptune Exoplanet π Mensae c and the Wider π Mensae Planetary System