Results 31 to 40 of about 1,371 (185)
THE SUN’S PHOTOSPHERIC CONVECTION SPECTRUM [PDF]
The Astrophysical Journal, 2015 Spectra of the cellular photospheric flows are determined from full-disk Doppler velocity observations acquired by the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO) spacecraft. Three different analysis methods are used to separately determine spectral coefficients representing the poloidal flows, the toroidal
David H. Hathaway +3 more
openaire +2 more sources
Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 3, June 2026.Abstract Recent advances in solar physics increasingly rely on automated identification of coronal structures using machine learning. Yet most studies emphasize scientific performance without evaluating feasibility for onboard deployment to prioritize downlink observations.
P. Gonidakis +11 more
wiley +1 more source
Space Weather, Volume 24, Issue 6, June 2026.Abstract Ejections of magnetized plasma from the Sun, known as coronal mass ejections, can drive major geomagnetic activity if Earth‐directed, and are therefore monitored by space weather forecasters. The current focus being the forecast of the arrival time of a coronal mass ejection at Earth and the level of geomagnetic impact.
L. M. Green +7 more
wiley +1 more source
Urbanisation Restructures but Does Not Reduce Freshwater Pond Biodiversity
Diversity and Distributions, Volume 32, Issue 6, June 2026.ABSTRACT Aim Urbanisation is a dominant driver of landscape change leading to widespread displacement, degradation and fragmentation of habitat for native species and numerous studies have documented loss of biodiversity in response. However, most studies focus on a small range of taxa (e.g., vertebrates, plants), leaving many other groups poorly ...
Julia M. Portmann +5 more
wiley +1 more source
A Cosmological Fireball with 16% Gamma-Ray Radiative Efficiency
The Astrophysical Journal Letters, 2023 Gamma-ray bursts (GRBs) are the most powerful explosions in the universe. How efficiently the jet converts its energy to radiation is a long-standing problem, which is poorly constrained.
Liang Li +11 more
doaj +1 more source
Extreme Value Analysis of Solar Green‐Line Corona During the Time Interval 1939–2025
Space Weather, Volume 24, Issue 5, May 2026.Abstract Predicting the probability of extreme solar events is critical to understanding how to mitigate risks associated with space weather disasters, as their occurrence can pose a threat to life and infrastructure on Earth or in near‐Earth orbit. In the present study, extreme value theory is applied to the daily modified coronal index (MCI) for the ...
Miao Wan +6 more
wiley +1 more source
CI chondrite Oued Chebeika 002 links asteroids Bennu and Ryugu to common parent body
Meteoritics &Planetary Science, Volume 61, Issue 5, Page 801-818, May 2026.Abstract CI chondrites are a compositionally primitive group of meteorites that have undergone extensive aqueous alteration, providing insights into the evolution of primitive planetesimals. Oued Chebeika 002 is the most pristine CI chondrite to date.
Megan Broussard +11 more
wiley +1 more source
Ryugu reference project: Recommendations from the measurement definition team
Meteoritics &Planetary Science, Volume 61, Issue 5, Page 819-848, May 2026.Abstract Sample return missions play a significant role in planetary science by providing pristine extraterrestrial materials. JAXA's Hayabusa2 and NASA's OSIRIS‐REx missions have returned samples from the C‐type asteroids Ryugu and Bennu, respectively. The chemical and mineralogical compositions of these samples closely resemble those of CI chondrites,
Tetsuya Yokoyama +16 more
wiley +1 more source
Clues to the photosphere emission origin of gamma-ray burst polarization
Astronomy & AstrophysicsContext. Despite more than half a century of research, the dominant radiation mechanism of gamma-ray burst (GRB) prompt emission remains unsolved. Some progress has been made through the analyses of the observational spectra of Swift/BAT, Konus/Wind, and
Meng Yan-Zhi +4 more
doaj +1 more source
Spectral Irradiance Observations and Projections for Solar Cycle 25
Earth and Space Science, Volume 13, Issue 4, April 2026.Abstract The Ozone Monitoring Instrument (OMI) on the Aura satellite makes near‐daily measurements of solar spectral irradiance (SSI) at wavelengths between 265 and 500 nm for instrument calibration purposes. The low degradation and exceptional stability of OMI's calibration during its lifetime facilitates the creation of a new 18‐year OMI Version 7 ...
Matthew T. DeLand +3 more
wiley +1 more source