Comets and Asteroids Archives

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Press Release

NASA Researchers Discover More Dark Comets

by Keith CowingDecember 10, 2024July 12, 2025

These celestial objects look like asteroids but act like comets now come in two flavors.

This image, taken by ESA’s Rosetta navigation camera, was taken from a about 53 miles from the center of Comet 67P/Churyumov-Gerasimenko on March 14, 2015. The image resolution is 24 feet per pixel and is cropped and processed to bring out the details of the comet's activity. ESA/Rosetta/NAVCAM

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Missions & Hardware, Press Release

NASA-Led Team Links Comet Water to Earth’s Oceans

by Keith CowingDecember 9, 2024December 9, 2024

Scientists find that cometary dust affects interpretation of spacecraft measurements, reopening the case for comets like 67P as potential sources of water for early Earth.

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

Ionizing Radiation Exposure On Arrokoth Shapes A Sugar World

by Keith CowingDecember 9, 2024December 9, 2024

The flyby of the New Horizons spacecraft of the Kuiper Belt Object Arrokoth revealed its reddish appearance and unraveled the unexpected presence of a methanol-rich surface.

Experiment setup of the TOF-MS in the MEFISTO chamber. Left panel: Lateral view of the experiment setup with the TOF-MS box mounted on the cooling plate. The electron beam from the top of the chamber impacts the ice in the sample holder at an incidence angle of 45◦ . Right panel: Photograph from the vantage point to the right of the sketch, showing the sample holder underneath the TOF-MS. The distance from the upper edge of the sample holder to the TOF-MS entrance is 100 mm. -- astro-ph.EP

Astrochemistry, Astrogeology, Comets and Asteroids, Enceladus, Europa, Icy Worlds, Status Report

Electron-Induced Radiolysis of Water Ice and the Buildup of Oxygen On Icy Worlds

by Keith CowingDecember 9, 2024December 9, 2024

Irradiation by energetic ions, electrons, and UV photons induces sputtering and chemical processes (radiolysis) in the surfaces of icy moons, comets, and icy grains.

NASA’s Office of Planetary Protection -- NASA

Biosignatures & Paleobiology, Comets and Asteroids, Mars, Meteorites & Asteroids, Microbiology & Virology, Missions & Hardware, NASA Astrobiology Program, Planetary Protection & Biosafety, Policy, Sample Return, Status Report

NASA’s Office of Planetary Protection Has A New Logo

by Keith CowingDecember 5, 2024December 5, 2024

Editor’s note: According to a LinkedIn post by James Benardini, Planetary Protection Officer at NASA: “NASA’s Office of Planetary Protection just released it’s new logo today! Excited to share this […]

Alma observation predictions to target water in HD 69830 showing the integrated flux in Jy.km.s−1 for the o-H2O 1029 − 936 transition at 321.22 GHz as a function of the temperature and the quantity of water. The black dashed line indicates the critical mass level when water starts self-shielding. The level at 0.012 Jy.km.s−1 is for a signalto-noise ratio of 5 represented by the solid white line labelled 5σ. This line is rather sensitive to low amounts of water and may allow for the detection of the first water gas disk in the near future. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Impact events, Status Report

An Impact-free Mechanism To Deliver Water To Terrestrial Planets And Exoplanets

by Keith CowingDecember 3, 2024December 3, 2024

To date, the most widespread scenario is that the Earth originated without water and was brought to the planet mainly due to impacts by wet asteroids coming from further out […]

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Impact events, Press Release

The Response of Planetary Atmospheres to the Impact of Icy Comets I: Tidally-Locked exo-Earths

by Keith CowingNovember 29, 2024November 29, 2024

Impacts by rocky and icy bodies are thought to have played a key role in shaping the composition of solar system objects, including the Earth’s habitability. Hence, it is likely […]

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, Status Report

He Awa Whiria: The Tidal Streams of Interstellar Objects

by Keith CowingNovember 28, 2024November 28, 2024

Upcoming surveys are likely to discover a new sample of interstellar objects (ISOs) within the Solar System, but questions remain about the origin and distribution of this population within the […]

Microscope image of one of the small fragments of asteroid 162173 Ryugu studied by scientists at the Advanced Photon Source. This fragment is roughly 400 microns in diameter, or about the width of six human hairs. Credit Image courtesy of Argonne National Laboratory

Astrochemistry, Astrogeology, Comets and Asteroids, Imaging & Spectroscopy, Meteorites & Asteroids, Planetary Protection & Biosafety, Press Release, Sample Return

Illuminating The Journey Of A 4-billion-year-old Asteroid

by Keith CowingNovember 25, 2024November 25, 2024

The Science Researchers at the Advanced Photon Source (APS) joined an international effort to study tiny fragments of a nearby asteroid. The APS, a Department of Energy Office of Science […]

A diagram of left-handed and right-handed versions of the amino acid isovaline, found in the Murchison meteorite. NASA

Astrochemistry, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Comets and Asteroids, Genomics, Proteomics, Bioinformatics, Imaging & Spectroscopy, Interstellar, Meteorites & Asteroids, Origin & Evolution of Life, Press Release

Astrochemistry: The Mystery of Life’s Handedness Deepens

by Keith CowingNovember 22, 2024November 22, 2024

The mystery of why life uses molecules with specific orientations has deepened with a NASA-funded discovery that RNA — a key molecule thought to have potentially held the instructions for […]