Results 21 to 30 of about 528 (133)
Adapted Empirical Modeling of Near‐Sun Solar‐Wind Speeds for Use in Ensemble Forecasts
Abstract Solar wind science and forecasting relies on empirical relations between modeled coronal magnetic‐field structure—particularly flux‐tube expansion and distance to coronal hole boundary—and solar‐wind speed. There is lots of uncertainty in these relations, creating large uncertainties in the inner‐boundary conditions to heliospheric models ...
N. O. Edward‐Inatimi +7 more
wiley +1 more source
The ORCA‐TWIN qCMOS Experiment I. Science Case and Commissioning at Calar Alto Observatory
ABSTRACT We describe a pilot study to explore a new generation of fast and low noise CMOS image sensors for time domain astronomy, using two remote telescopes with a baseline of 1635 km. The experiment involves direct imaging with novel qCMOS image sensor technology that combines fast readout with sub‐electron readout noise.
Martin M. Roth +20 more
wiley +1 more source
Centre-to-limb properties of small, photospheric quiet-Sun jets [PDF]
9 pages, 9 ...
Rubio da Costa, F. +4 more
openaire +3 more sources
Forecasting Continuum Intensity for Solar Active Region Emergence Prediction Using Transformers
Abstract Early and accurate prediction of solar active region (AR) emergence is crucial for space weather forecasting. Building on established Long Short‐Term Memory (LSTM) based approaches for forecasting the continuum intensity decrease associated with AR emergence, this work expands the modeling with new architectures and targets.
Jonas Tirona +7 more
wiley +1 more source
MODELING THE SUN’S SMALL-SCALE GLOBAL PHOTOSPHERIC MAGNETIC FIELD [PDF]
ABSTRACT We present a new model for the Sun’s global photospheric magnetic field during a deep minimum of activity, in which no active regions emerge. The emergence and subsequent evolution of small-scale magnetic features across the full solar surface is simulated, subject to the influence of a global supergranular flow pattern ...
K. A. Meyer, D. H. Mackay
openaire +3 more sources
Abstract The Potential Field Source Surface (PFSS) extrapolation is a method for estimating the large scale coronal magnetic field from photospheric magnetograms. The source surface serves as the outer boundary of its solution domain, and is typically a spherical surface.
Shiouhe Wang +4 more
wiley +1 more source
Search for photospheric footpoints of quiet Sun transition region loops [PDF]
CONTEXT:The footpoints of quiet Sun Transition Region (TR) loops do not seem to coincide with the photospheric magnetic structures appearing in traditional low-sensitivity magnetograms. AIMS: To look for the so-far unidentified photospheric footpoints of TR loops using G-band bright points (BPs) as proxies for photospheric magnetic field concentrations.
Sánchez Almeida, J. +5 more
openaire +5 more sources
The Sun's Global Photospheric and Coronal Magnetic Fields: Observations and Models [PDF]
61 pages, 18 figures.
Mackay, Duncan Hendry +1 more
openaire +5 more sources
The UK Met Office’s Coronal Mass Ejection (CME) Ensemble Prediction System
Abstract We describe the 24‐member Coronal Mass Ejection (CME) ensemble prediction system that is used operationally at the UK's Met Office Space Weather Operations Center (MOSWOC) to forecast the arrival time of CMEs at Earth. The ensemble system was built on ad‐hoc assumptions and there is the need to investigate whether the technique can be improved
Siegfried Gonzi +8 more
wiley +1 more source
Noble gases and nitrogen in material from asteroid Bennu
Abstract We report the elemental and isotopic abundances of all stable noble gases (helium, neon, argon, krypton, and xenon) in eight particles from asteroid Bennu returned by NASA's OSIRIS‐REx mission. We also report nitrogen abundances and isotopic ratios that were analyzed alongside neon and argon in four additional Bennu particles.
B. Marty +7 more
wiley +1 more source

