Results 101 to 110 of about 306 (178)

The First Detection of Molecular Activity in the Largest Known Oort Cloud Comet: ALMA Imaging of C/2014 UN271 (Bernardinelli–Bernstein) at 16.6 au from the Sun

The Astrophysical Journal Letters
We report observations of comet C/2014 UN271 (Bernardinelli–Bernstein) carried out on UT 2024 March 8 and 17 at a heliocentric distance ( r _H ) of 16.6 au using the Atacama Large Millimeter/submillimeter Array (ALMA).
Nathan X. Roth, Stefanie N. Milam, Martin A. Cordiner, Dominique Bockelée-Morvan, Nicolas Biver, Michael S. P. Kelley, Anthony J. Remijan, Steven B. Charnley, Carrie E. Holt, Kiernan D. Foster, Joseph Chatelain, Edward Gomez, Sarah Greenstreet, Tim Lister, Helen Usher   +14 more
doaj   +1 more source

Perihelion Asymmetry in the Water Production Rate of the Interstellar Object 3I/ATLAS

The Astrophysical Journal Letters
3I/ATLAS is an interstellar object whose activity provides critical insights into its composition and origin. However, due to its orbital geometry, the object is too close to the Sun near perihelion to be observed from the ground, and space-based ...
Hanjie Tan, Xiaoran Yan, Jian-Yang Li
doaj   +1 more source

Cometary Comae-Surface Links: The Physics of Gas and Dust from the Surface to a Spacecraft. [PDF]

Space Sci Rev, 2020
Marschall R, Skorov Y, Zakharov V, Rezac L, Gerig SB, Christou C, Dadzie SK, Migliorini A, Rinaldi G, Agarwal J, Vincent JB, Kappel D.   +11 more
europepmc   +1 more source

A Large Outburst, Coma Asymmetries, and the Color of Comet 243P/NEAT

The Planetary Science Journal
Water ice is a fundamental building material of comets and other bodies in the outer solar system. Yet the properties of cometary water ice are challenging to study, due to its volatility and the typical distances at which comets are observed.
Michael S. P. Kelley, Silvia Protopapa, Dennis Bodewits, Aren N. Heinze, Youssef Moulane, Quanzhi Ye, Bryce Bolin, Simon Conseil, Tony L. Farnham, Lori Feaga, Xing Gao, Chih-Hao Hsia, Emmanuel Jehin, Shrinivas R. Kulkarni, Russ R. Laher, Tim Lister, Frank J. Masci, Josiah Purdum, Bin Yang   +18 more
doaj   +1 more source

A Dormant Captured Oort Cloud Comet Awakens: (18916) 2000 OG44

The Astrophysical Journal Letters
We report the discovery of activity emanating from (18916) 2000 OG _44 (alternately designated 1977 SD), a minor planet previously reported to be both an extinct comet and an asteroid on a cometary orbit. We observed 2000 OG _44 with a thin tail oriented
Colin Orion Chandler, William J. Oldroyd, Chadwick A. Trujillo, Dmitrii E. Vavilov, William A. Burris   +4 more
doaj   +1 more source

CH3OH and HCN in Interstellar Comet 3I/ATLAS Mapped with the ALMA Atacama Compact Array: Distinct Outgassing Behaviors and a Remarkably High CH3OH/HCN Production Rate Ratio

The Astrophysical Journal Letters
We report the detection of methanol (CH _3 OH) toward interstellar comet 3I/ATLAS using the Atacama Compact Array of the Atacama Large Millimeter/submillimeter Array (ALMA) on UT 2025 August 28, September 18 and 22, and October 1 and of hydrogen cyanide (
Nathan X. Roth, Martin A. Cordiner, Dominique Bockelée-Morvan, Nicolas Biver, Jacques Crovisier, Stefanie N. Milam, Emmanuel Lellouch, Pablo Santos-Sanz, Dariusz C. Lis, Chunhua Qi, K. D. Foster, Jérémie Boissier, Kenji Furuya, Raphael Moreno, Steven B. Charnley, Anthony J. Remijan, Yi-Jehng Kuan, Lillian X. Hart   +17 more
doaj   +1 more source

Modeling Ice and Dust in Comet C/2017 K2 (Pan-STARRS)’s Coma

The Planetary Science Journal
C/2017 K2 (Pan-STARRS) is a long-period comet that has been active since 24 au inbound and likely as far out as 35 au, far beyond where the sublimation of water ice can power cometary activity.
Megan Firgard, Theodore Kareta
doaj   +1 more source

The Formation of Bilobate Comet Shapes through Sublimative Torques. [PDF]

Planet Sci J, 2021
Safrit TK, Steckloff JK, Bosh AS, Nesvorny D, Walsh K, Brasser R, Minton DA.   +6 more
europepmc   +1 more source

Organic Matter in Cometary Environments. [PDF]

Life (Basel), 2021
McKay AJ, Roth NX.
europepmc   +1 more source

Electric Fields Can Assist Prebiotic Reactivity on Hydrogen Cyanide Surfaces. [PDF]

ACS Cent Sci
Cappelletti M, Sandström H, Rahm M.
europepmc   +1 more source