Category Astronomy/Space

Craters on the surface of the asteroid 21 Lutetia. Credit: ESA

An international study reveals that asteroids have endured a multitude of impact strikes since their formation 4,565 million years ago. Scientists have reconstructed a timeline of these collisions using a physics-based model which reproduces the process through time, comparing its results with present-day information about chondrite meteorites.

The size distribution of the objects which make up the asteroid belt between Mars and Jupiter indicates that these asteroids have been struck by projectiles >20cm in size at least 100 million times. The resultant craters from these strikes are proportional to both the diameters and the velocities of these projectiles.

The information compiled on ordinary chondrites indicates that these m...

Magnetohydrodynamic turbulence powered by neutrino-driven convection behind the stalled shock of a core-collapse supernova simulation. This simulation shows that the presence of rotation and weak magnetic fields dramatically impacts the development of the supernova mechanism as compared to non-rotating, non-magnetic stars. The nascent neutron star is just barely visible in the center below the turbulent convection. Credit: Sean M. Couch, Michigan State University

Michigan State University researchers are using Mira to perform large-scale 3D simulations of the final moments of a supernova’s life cycle...

The VLA radio map of the region around the Great Red Spot in Jupiter’s atmosphere shows complex upwellings and downwellings of ammonia gas (upper map), that shape the colorful cloud layers seen in the approximately true-color Hubble map (lower map). Two radio wavelengths are shown in blue (2 cm) and gold (3 cm), probing depths of 30-90 kilometers below the clouds. Credit: Radio: Michael H. Wong, Imke de Pater (UC Berkeley), Robert J. Sault (Univ. Melbourne). Optical: NASA, ESA, A.A. Simon (GSFC), M.H. Wong (UC Berkeley), and G.S. Orton (JPL-Caltech)

Astronomers using the upgraded Karl G...

This image shows the installation of the mini-eTPC demonstrator detector during on-line test beams at the 9 MV Tandem accelerator facility at IFIN-HH, Magurele, Romania. From left: Jan Stefan Bihalowicz, Lukasz Janiak, Marcin Zaremba. Credit: Faculty of Physics, University of Warsaw

The most intense source of gamma radiation constructed to date will soon become operational at the ELI Nuclear Physics research facility. It will be possible to study reactions that reveal the details of many processes occurring within stars, in particular those leading to the formation of oxygen.

All oxygen was ultimately formed through thermonuclear reactions deep inside stars. Lab studies of astrophysical processes leading to oxygen formation are extremely important...