Results 41 to 50 of about 2,093,430 (321)

Activity of Halley-type Comets 12P/Pons–Brooks and 13P/Olbers from SOHO/SWAN Observations

The Planetary Science Journal
The Solar Wind ANisotropies (SWAN) all-sky hydrogen Ly α camera on the Solar and Heliosphere Observatory (SOHO) observed the hydrogen coma of Halley-type comet (HTC) 12P/Pons–Brooks from SOHO’s halo orbit around L1 throughout its 2023–2024 apparition ...
M. R. Combi, T. Mäkinen, J.-L. Bertaux, E. Quémerais, S. Ferron   +4 more
doaj   +1 more source

On the origin of Comet Encke [PDF]

Monthly Notices of the Royal Astronomical Society, 1996
Numerical integrations are performed on test-particle orbits similar to those of 2PlEncke and (6063) Jason. For purely gravitational integrations, or integrations with non-gravitational forces applied of a magnitude similar to those currently observed for 2PlEncke, the orbits do not alter substantially, all remaining decoupled from Jupiter.
Steel, D. I., Asher, D. J.
openaire   +1 more source

Origin of Molecular Oxygen in Comets: Current Knowledge and Perspectives [PDF]

Space Science Reviews, 2018
The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument onboard the Rosetta spacecraft has measured molecular oxygen (O2) in the coma of comet 67P/Churyumov-Gerasimenko (67P/C-G) in surprisingly high abundances.
A. Luspay-Kuti, O. Mousis, J. Lunine, Y. Ellinger, F. Pauzat, U. Raut, A. Bouquet, K. Mandt, R. Maggiolo, T. Ronnet, B. Brugger, O. Ozgurel, S. Fuselier   +12 more
semanticscholar   +2 more sources

Photocatalytic Water Splitting on the Lunar Surface: Prospects for In Situ Resource Utilization

Advanced Materials Interfaces, EarlyView.
Water has been found in craters on the moon nearby locations which are illuminated >80% of the time. Photocatalysis uses energy from sunlight to drive chemical reactions such as water splitting to produce oxygen and hydrogen. It is a scalable technology that requires lighter equipment and utilizes resources available on the moon. ABSTRACT The discovery
Ranjani Kalyan, Thomas D. Small, Gregory F. Metha, Mahmoud Adel Hamza, Thomas J. O'Dea, Yideng Shen, Cameron J. Shearer   +6 more
wiley   +1 more source

Interstellar Object 3I/ATLAS Observed from Mars by China’s Tianwen-1 Spacecraft

The Astrophysical Journal Letters
China’s Tianwen-1 Mars orbiter successfully imaged the third interstellar object, 3I/ATLAS, during its close encounter with Mars using the onboard HiRIC CMOS camera. This is China’s first deep-space observation of an astronomical object.
Xin Ren, Wei Yan, Ruining Zhao, Shu Wang, Xingye Gao, Qiang Fu, Qing Zhang, Bin Yang, Man-To Hui, Zhiyong Xiao, Xiaodong Liu, Cunhui Li, Renhao Tian, Wenguang Liu, Dong Wang, Shaoran Liu, Cong Ren, Jie Dong, Xinbo Zhu, Pan Xie, Jian-Yang Li, Yan Geng, Jianjun Liu   +22 more
doaj   +1 more source

Chromosomal Instability Drives Glioblastoma Heterogeneity and Therapeutic Opportunities

Advanced Science, EarlyView.
ABSTRACT Glioblastoma, the most aggressive and lethal form of brain cancer, is defined by profound genomic instability, with Chromosomal Instability (CIN) playing a central role in driving tumor progression, therapy resistance, and poor prognosis. CIN is characterized by numerical and structural alterations, is driven by mechanisms such as mitotic ...
Amarnath Pal, Milan Patra, Rianita Mondal, Shubhasis Haldar   +3 more
wiley   +1 more source

Postperihelion Coma Composition of the Interstellar Comet 3I/ATLAS from Optical Spectroscopy

The Astrophysical Journal Letters
We present multiepoch optical spectroscopy of the interstellar comet 3I/ATLAS obtained between 2025 December and 2026 January (heliocentric distances of 1.8–3.3 au), yielding postperihelion production rates and mixing ratios for CN, C _3 , C _2 , CH, and
Ruining Zhao, Xiliang Zhang, Bin Yang, Xiangyu Fan, Shu Wang, Yang Huang, Jifeng Liu   +6 more
doaj   +1 more source

The Origins of Comets

Eos, Transactions American Geophysical Union, 1992
Do we live in astronomically disappointing times? Are the skies duller than they've been in the past‐comets less spectacular, meteors less frequent, and the zodiacal lights dimmer? Certainly as an amateur astronomer I have been haunted by that impression.
openaire   +1 more source

SMAD4 Palmitoylation Drives a Metabolic‐Transcriptional Circuit to Promote Tumorigenesis and Confers Radiosensitivity in Pancreatic Cancer

Advanced Science, EarlyView.
This study identifies palmitoylation as a novel regulatory modification of SMAD4, mediated by ZDHHC22/APT2. It activates fatty acid synthesis, creating a self‐reinforcing SMAD4–FASN–palmitate feedback loop that drives pancreatic cancer growth and enhances radiotherapy sensitivity.
Yang Wang, Shan Zhang, Junping Bai, Xiaobing Li, Yi Han, Min Ji, Chongyi Jiang, Xiaobei Ge, Tianyu Yu, Yongying Hou, Jun Zhang, Wangting Li, Yiran Song, Jiaying Cai, Yingqun Zhou, Liwei An, Feng Wang   +16 more
wiley   +1 more source

Origin of comets [PDF]

Astronomical School’s Report, 2003
Three basic conceptions of origin of comets are under discussion. The first one belongs to Laplace who supposed that comets are becoming the members of the Solar system being captured by a giant planet, e.g. Jupiter. It is the hypothesis of capture. Oort supposed that there is a giant cloud of cometary nuclei at the heliocentric distance ∼105 AU.
openaire   +2 more sources