An international physics team with the participation of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has proposed a new concept that may allow selected cosmic extreme processes to be studied in the laboratory in the future. A special setup of two high-intensity laser beams could create conditions similar to those found near neutron stars, for example. An antimatter jet is generated and accelerated very efficiently, as the experts report in the journal Communications Physics (DOI: 10.1038/s42005-021-00636-x).
A new survey of our home galaxy, the Milky Way, combines the capabilities of the Very Large Array and the Effelsberg telescope in Germany to provide astronomers with valuable new insights into how stars much more massive than the Sun are formed.
A new approach to analysing the development of magnetic tangles on the Sun has led to a breakthrough in a longstanding debate about how solar energy is injected into the solar atmosphere before being released into space, causing space weather events. The first direct evidence that field lines become knotted before they emerge at the visible surface of the Sun has implications for our ability to predict the behaviour of active regions and the nature of the solar interior.
According to the latest cosmological models, large spiral galaxies such as the Milky Way grew by absorbing smaller galaxies, by a sort of galactic cannibalism. Evidence for this is given by very large structures, the tidal stellar streams, which are observed around them, which are the remains of these satellite galaxies. But the full histories of the majority of these cases are hard to study, because these flows of stars are very faint, and only the remains of the most recent mergers have been detected.
Scientists show for the first time that 'stealth' coronal mass ejections, a type of solar storm, can be detected early on the Sun's surface. This could help put measures in place that limit damage to technology and energy grids on Earth from the electromagnetic radiation. The new techniques can be implemented immediately, and their power to forecast risky events will become even greater once the new Solar Orbiter and similar spacecraft become fully operational.
A team of solar physicists led by Laurent Gizon of the Max Planck Institute for Solar System Research (MPS) and the University of Goettingen in Germany has reported the discovery of global oscillations of the Sun with very long periods, comparable to the 27-day solar rotation period. The oscillations manifest themselves at the solar surface as swirling motions with speeds on the order of 5 kilometers per hour.
Any life identified on planets orbiting white dwarf stars almost certainly evolved after the star's death, says a new study led by the University of Warwick that reveals the consequences of the intense and furious stellar winds that will batter a planet as its star is dying. The research is published in Monthly Notices of the Royal Astronomical Society, and lead author Dr Dimitri Veras will present it today (21 July) at the online National Astronomy Meeting (NAM 2021).
Black holes with masses equivalent to millions of suns do put a brake on the birth of new stars, say astronomers. Using machine learning and three state of the art simulations to back up results from a large sky survey, the researchers resolve a 20-year long debate on the formation of stars. Joanna Piotrowska, a PhD student at the University of Cambridge, will present the new work today (Tuesday 20 July) at the virtual National Astronomy Meeting (NAM 2021).
Scientists from the University of Graz, Kanzelhöhe Observatory, Skoltech, and the World Data Center SILSO at the Royal Observatory of Belgium, have presented the Catalogue of Hemispheric Sunspot Numbers. It will enable more accurate predictions of the solar cycle and space weather, which can affect human-made infrastructure both on Earth and in orbit.
The final stage of cataclysmic explosions of dying massive stars, called supernovae, could pack an up to six times bigger punch on the surrounding interstellar gas with the help of cosmic rays, according to a new study led by researchers at the University of Oxford. The work will be presented by PhD student Francisco Rodríguez Montero today (19 July) at the virtual National Astronomy Meeting (NAM 2021).