Related papers: The carbon monoxide-rich interstellar comet 2I/Bor…
The 18O/17O ratio of the Solar System is 5.2 while that of the interstellar medium (ISM) and young stellar objects is ~4. This difference cannot be explained by pollution of the Sun's natal molecular cloud by 18O-rich supernova ejecta…
Cometary comae are generally depleted in nitrogen. The main carriers for volatile nitrogen in comets are NH3 and HCN. It is known that ammonia readily combines with many acids like e.g. HCN, HNCO, HCOOH, etc. encountered in the interstellar…
Since 1950 when Oort published his paper on the structure of the cloud of comets it is believed that stars passing near this hypothetical cometary reservoir play an important role in the dynamical evolution of long period comets and…
The fragile structure of chondritic-porous interplanetary dust particles (CP- IDPs) and their minimal parent-body alteration have led researchers to believe these particles originate in comets rather than asteroids where aqueous and thermal…
Remote observations of comets, especially using high spectral resolution millimeter spectroscopy, have enabled the detection of over 25 molecules in comets for the last twenty years. Among the molecules identified at radio wavelengths,…
Comets are made of volatile and refractory material and naturally experience various degrees of sublimation as they orbit around the Sun. This gas release, accompanied by dust, represents what is traditionally described as activity.…
Complex organic molecules (COMs) have been detected abundantly at various stages of star formation, particularly in the warm protostellar phase. The progress in gas-phase measurements has been accelerated by the advent of the Atacama Large…
We present analysis of observations of CO2 and OI emission in three comets to measure the CO2 abundance and evaluate the possibility of employing observations of OI emission in comets as a proxy for CO2. We obtained NIR imaging sensitive to…
Interstellar hydrides -- that is, molecules containing a single heavy element atom with one or more hydrogen atoms -- were among the first molecules detected outside the solar system. They lie at the root of interstellar chemistry, being…
Comets hold answers to mysteries of the Solar System by recording presolar history, the initial states of planet formation and prebiotic organics and volatiles to the early Earth. Analysis of returned samples from a comet nucleus will…
Hyperactive comet activity typically becomes evident beyond the frost line (3 to 4 au) where it becomes too cold for water-ice to sublimate. If carbon monoxide (CO) and carbon dioxide (CO2) are the species that drive activity at…
Cool, evolved stars are the main source of chemical enrichment of the interstellar medium (ISM), and understanding their mass loss and structure offers a unique opportunity to study the cycle of matter in the Universe. Pulsation,…
Far ultraviolet observations of comets yield information about the energetic processes that dissociate the sublimated gases from their primitive surfaces. Understanding which emission processes are dominant, their effects on the observed…
Alice is a far-ultraviolet imaging spectrograph onboard Rosetta that, amongst multiple objectives, is designed to observe emissions from various atomic and molecular species from within the coma of comet 67P/Churyumov-Gerasimenko. The…
We present an analysis of the results of photometric investigations of two distant comets, C/2002 VQ94 (LINEAR) and 29P/Schwassmann-Wachmann 1, obtained with the 6m telescope of the Special Astrophysical Observatory of the Russian Academy…
We present multi-epoch optical spectroscopy of the interstellar comet 3I/ATLAS obtained between December 2025 and January 2026 (heliocentric distances 1.8-3.3 au), yielding post-perihelion production rates and mixing ratios for CN, C$_3$,…
Ices are the main carriers of volatiles in protoplanetary disks and are crucial to our understanding of the chemistry that ultimately sets the organic composition of planets. The ERS program Ice Age on the JWST follows the ice evolution…
The extremely thin atmosphere of Jupiter's volcanic moon Io primarily consists of sulfur (S), sodium (Na), and oxygen (O) molecules that are controlled by the combination of the sublimation and volcanic outgasses. We present the first…
Tiny meteoroids entering the Earth's atmosphere and inducing meteor showers have long been thought to originate partly from cometary dust. Together with other dust particles, they form a huge cloud around the Sun, the zodiacal cloud. From…
Cold ($\sim$10 K) and dense ($\sim$10$^{5}$ cm$^{-3}$) cores of gas and dust within molecular clouds, known as starless and dynamically evolved prestellar cores, are the birthplaces of low-mass ($M$ $\leq$ few M$_\odot$) stars. As…