Results 61 to 70 of about 4,973 (222)

From Flybys to Sample Return: A Review of Space Probes and Robotic Sampling Technologies for Small Bodies

Journal of Field Robotics, EarlyView.
ABSTRACT As a crucial puzzle piece of deep space exploration, exploring small bodies can provide significant scientific insights and valuable mineral resources. Unlike missions to the Moon and Mars, small‐body missions pose distinct technical challenges, including communication delays, weak gravity, and uncertain environments. This paper reviews a full
Xin Zhang, Hao Zhou, Dalin Zhou, Zhaojie Ju   +3 more
wiley   +1 more source

Modelling accretion disk winds in quasars

, 2014
Outflows are ubiquitous in active galactic nuclei (AGN). They can take the form of either dramatic radio jets, which extend vast distances into the inter-galactic medium, or of much smaller scale winds - whose existence can be inferred only indirectly ...
Nick Higginbottom, Higginbottom, Nicholas   +1 more
core   +1 more source

Cosmic Evolution of Nearby Radio Active Galactic Nuclei

Journal of Physics: Conference Series, 2019
Abstract The exact formation mechanism of massive galaxy in the universe still become an open question in modern astrophysics. Radio emission from active galactic nucleus (AGN) is known to be suppressing stellar growth in the most massive galaxies, thus becoming significant ingredient in modeling galaxy formation process.
Taufik Andika, I., Ikbal Arifyanto, M., Istiqomah, A., Amalina, S., Aprilia, Hakim, M.   +5 more
openaire   +2 more sources

A Low‐Power Radioisotope XRF Spectrometer for Detection of Light Elements on Planetary Missions

X-Ray Spectrometry, EarlyView.
ABSTRACT Current X‐ray spectrometers for in situ geochemical analysis on planetary missions typically rely either on X‐ray tubes, which demand electrical power and add mass and thermal complexity, or on alpha particle X‐ray spectrometers (APXS) that use rare 244Cm$$ {}^{244}\mathrm{Cm} $$ sources, and come with severe concerns on radiation safety and ...
Leandro Silveri, Artem Knyazev, Hashem Alaidaros, Maryam Manzoor Amanullah, Zach Ioannou, Tengiz Ibrayev, Danish Khan, Sara Leardini, Laura Manenti, Simi Maria Emilia Mangani, Safa Naseem, Sandhya Sharma, Sara Trevisan, Alia Zino, Francesco Arneodo   +14 more
wiley   +1 more source

Very high energy gamma ray observations of southern hemisphere blazars [PDF]

, 1997
This thesis is concerned with very high energy γ-ray observations of blazars observable from the southern hemisphere. The data presented were obtained using the recently deployed University of Durham Mark 6 high sensitivity Čerenkov telescope. Chapters 1
Dickinson, M.R., Dickinson, Mark R.
core  

Probing galaxy evolution below the noise threshold with radio observations [PDF]

, 2020
Philosophiae Doctor - PhDThe faint radio population consisting of star forming galaxies (SFG) and radio-quiet active galactic nuclei (AGN) is important in the study of galaxy evolution.
Malefahlo, Eliab D
core   +1 more source

The Merging Galaxy Cluster Environment Affects the Morphology of Radio Active Galactic Nuclei

The Astrophysical Journal
It has previously been found that the galaxy cluster environment can affect the fueling and evolution of active galactic nuclei (AGN). This work examines the effect of the merging cluster environment on the properties of radio AGN by comparing the radio ...
Mary Rickel, Emily Moravec, Yjan A. Gordon, Martin J. Hardcastle, Jonathon C. S. Pierce, Lawrence E. Bilton, Ian D. Roberts   +6 more
doaj   +1 more source

Changing-Look AGNs or Short-Lived Radio Sources?

Frontiers in Astronomy and Space Sciences, 2017
The evolution of extragalactic radio sources has been a fundamental problem in the study of active galactic nuclei for many years. A standard evolutionary model has been created based on observations of a wide range of radio sources.
Aleksandra Wołowska, Magdalena Kunert-Bajraszewska, Kunal Mooley, Gregg Hallinan   +3 more
doaj   +1 more source

The SVP–FRO6 Module Integrates the Control of Leaf Senescence and Flowering in Arabidopsis

Plant, Cell &Environment, EarlyView.
ABSTRACT Plants coordinate major developmental transitions by integrating intrinsic genetic programs with environmental signals, where nutrient availability serves as a critical external factor shaping growth and fitness. Iron (Fe), an essential micronutrient for cellular respiration and photosynthesis, is strictly regulated through sophisticated ...
Hyunsu Park, Yeong Seon Yoon, Sanghoon Park, Ukcheol Jeong, Hyeyoung Choi, Hyunwoo Oh, Dovran Shamamedov, Zhonghai Li, Hye Ryun Woo   +8 more
wiley   +1 more source

Optical polarimetry studies of Seyfert galaxies [PDF]

, 1999
Optical imaging polarimetry has been performed on seven nearby Seyfert galaxies, three with face-on and four with edge-on host galaxies of various morphological classifications.
Felton, Michelle Ann
core