A shower of matter from space millions of years ago could have led to drastic changes in the Earth’s climate, followed by the extinction of life on a massive scale, which also killed off the dinosaurs. This at least is a theory put forward by scientists from the University of Bonn. Normally, the solar wind acts as a shield against showers of cosmic particles, which prevents too many energy-rich particles from raining down on our atmosphere. Since 1997 scientists from Bonn, funded by the German Research Council (Deutsche Forschungsgemeinschaft or DFG), have been examining how and why this gigantic shield works.
They were the undisputed masters of a whole geological era until they suddenly disappeared 65 million years ago. ‘Perhaps Earth just became too damp and too cold for dinosaurs at that time,’ Professor Hans Jörg Fahr from the Bonn Institute of Astrophysics and Extraterrestrial Research surmises. The reason for the sudden change in climate could have been excessive pressure on our cosmic umbrella.
The solar system does not stand still, in fact it orbits the centre of the Milky Way once every 250 million years. In the process it also passes through dense clouds of interstellar matter, which causes problems for the solar wind and thus for the Earth. Whereas the solar wind normally protects the Earth from a hail of interstellar particles like a huge bullet-proof vest, there are then suddenly up to a hundred times more particles raining down into the earth’s atmosphere at enormous speeds. On impact they smash the air molecules into electrically charged fragments. These function as condensation nuclei on which droplets of water form. “The result is dense cloud cover with greater precipitation and sinking temperatures,” says Professor Fahr, who bases his remarks on research worldwide.
Professor Hans Jörg Fahr | alphagalileo
Hundreds of bubble streams link biology, seismology off Washington's coast
22.03.2019 | University of Washington
Atmospheric scientists reveal the effect of sea-ice loss on Arctic warming
11.03.2019 | Institute of Atmospheric Physics, Chinese Academy of Sciences
DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.
The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...
Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.
The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...
Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.
Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...
The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.
A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...
Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.
"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...
11.03.2019 | Event News
01.03.2019 | Event News
28.02.2019 | Event News
25.03.2019 | Trade Fair News
25.03.2019 | Life Sciences
25.03.2019 | Information Technology