Results 111 to 120 of about 74,488 (217)

Hydromagnesite Precipitation in an Ultramafic‐Hosted Alkaline Lake: Insights From Lake Salda for Jezero Crater, Mars

Journal of Geophysical Research: Planets, Volume 131, Issue 5, May 2026.
Abstract Lake Salda (SW Turkey) is one of the most compelling terrestrial analogs for Jezero Crater on Mars due to its highly alkaline, Mg‐rich waters and hydromagnesite‐forming microbialites. This study integrates hydrochemical measurements, saturation‐index modeling, SEM–TEM imaging, and X‐ray diffraction (XRD) analysis to disentangle the biotic and ...
Mirosław Słowakiewicz, Mario Borrelli, Gürçay Kıvanç Akyıldız, Marek Szczerba, Ezher Tagliasacchi, Edoardo Perri   +5 more
wiley   +1 more source

Microspherules formed by lightning strikes

Meteoritics &Planetary Science, Volume 61, Issue 5, Page 743-767, May 2026.
Abstract Natural microspherules are formed by high‐temperature processes and are present throughout the geologic record to the present day. We report the discovery of large numbers of microspherules recovered from a rock pavement in the Pilbara region, Western Australia.
M. R. Boyd, M. J. Genge, A. G. Tomkins
wiley   +1 more source

Mid-infrared Variability in Nearby Galaxies from the MaNGA Sample

The Astrophysical Journal
We use mid-infrared variability in galaxies to search for active galactic nuclei (AGN) in the local universe. We use a sample of 10,220 galaxies from the Mapping Nearby Galaxies at Apache Point Observatory survey, part of the Sloan Digital Sky Survey ...
Aashay Pai, Michael R. Blanton, John Moustakas   +2 more
doaj   +1 more source

A Catalog of Broad Hα and Hβ Active Galactic Nuclei in MaNGA

The Astrophysical Journal
Broad H α and H β emission lines (FWHM > 1000 km s ^−1 ) are incredibly efficient tracers of the high-velocity clouds encircling active galactic nuclei (AGNs).
James Negus, Julia M. Comerford, Francisco Müller Sánchez   +2 more
doaj   +1 more source

Variability-selected low luminosity AGNs in the SA57 and in the CDFS

, 2009
Low Luminosity Active Galactic Nuclei (LLAGNs) are contaminated by the light of their host galaxies, thus they cannot be detected by the usual colour techniques. For this reason their evolution in cosmic time is poorly known.
Boutsia, K., Trevese, D., Vagnetti, F.
core  

The QPO in RE J1034+396 Originates in the Hot Corona

The Astrophysical Journal
RE J1034+396 is one of the few active galactic nuclei (AGNs) with a significant quasiperiodic oscillation (QPO). The QPO has been observed in over 1 Ms of XMM-Newton observations spanning over a decade. We investigate the power spectral density function (
Chloe S. Taylor, Dan R. Wilkins, Steven W. Allen   +2 more
doaj   +1 more source

Gamma rays from active galactic nuclei [PDF]

The general properties of Active Galactic Nuclei (AGN) and quasars are reviewed with emphasis on their continuum spectral emission. Two general classes of models for the continuum are outlined and critically reviewed in view of the impending GRO (Gamma ...
Kazanas, Demosthenes
core   +1 more source

ABSTRACTS

Precision Radiation Oncology, EarlyView.
wiley   +1 more source

VLA FRAMEx. III. Circumnuclear Radio Emission Mechanisms in Hard X-Ray Selected Active Galactic Nuclei

The Astrophysical Journal
We present Stokes I continuum analysis for a volume-limited sample (
Andrew J. Sargent, Alexander J. van der Horst, Megan C. Johnson, Nathan J. Secrest, Travis C. Fischer, Onic I. Shuvo, Macon A. Magno, Luis C. Fernandez   +7 more
doaj   +1 more source

VLA FRAMEx. II. Radio Spectra of Nearby Active Galactic Nuclei at Subarcsecond Resolution

The Astrophysical Journal
We present 4–12 GHz in-band spectral energy distributions with accompanying 6 GHz and 10 GHz imaging results for a volume-complete sample ( 0) spectral indices.
Andrew J. Sargent, Alexander J. van der Horst, Megan C. Johnson, Travis C. Fischer, Nathan J. Secrest, Phil J. Cigan, Onic I. Shuvo, Krista L. Smith   +7 more
doaj   +1 more source