The results will be reported in two papers in the 1st November issue of Nature.
Although the papers deal with two entirely different types of objects, newly forming stars in our Galaxy and distant quasars, they solve very similar problems that have lacked direct observational evidence in tackling them.
Stars form from molecular gas clouds which collapse under gravity. However, as the cloud collapses it spins up, gaining angular momentum – which depends on the mass and rotational speed, and the clouds should fly apart preventing the star forming. Yet we know stars do form! It has been known for sometime that newly forming stars produce jets and outflows of material but their exact role and how the jets are constrained and don’t simply dissipate, has not been clear. The University of Hertfordshire team, using the Anglo-Australian Observatory, NSW, Australia, studied the jets associated with a young star, and showed that helical magnetic fields, rather like the coils of a spring, are able to keep the jets collimated and that this aids the removal of angular momentum, thereby allowing the star to increase its mass.
Quasars are the very bright cores of galaxies and are believed to be powered by supermassive black holes. These have masses billions of times that of the Sun, and material is fed into the black hole through a disk of material around it, known as an accretion disk. As material is accreted onto the disk, it starts to spin very quickly and this prevents further material being added, and the quasar would then run out of new fuel and switch off. Observations at the William Herschel Telescope La Palma, made by teams from the University of Hertfordshire and the Rochester Institute of Technology, New York, have shown that powerful rotating winds are launched from the accretion disk, and this reduces the angular momentum of the disk and allows the black hole to be fed and the quasar to continue shining brightly.
Observations for both discoveries used optical and infrared instruments sensitive to the polarization of light (as are Polaroid sun glasses). “The University of Hertfordshire has a world reputation for astronomical polarimetry”, said Professor James Hough, Director of Astronomy Research, and added that “these results showed that polarimetry is a key technique in many areas of astrophysics ranging from stars to distant quasars”.
Helene Murphy | alfa
Early opaque universe linked to galaxy scarcity
15.08.2018 | University of California - Riverside
MSU astronomers discovered supermassive black hole in an ultracompact dwarf galaxy
14.08.2018 | Lomonosov Moscow State University
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.
Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
15.08.2018 | Physics and Astronomy
15.08.2018 | Materials Sciences
15.08.2018 | Life Sciences