Illustration of the white dwarf and its companion HD49798. If it was possible to look at the system up-close, it would look something like this. Credits: Francesco Mereghetti, background image: NASA, ESA and T.M. Brown (STScI)
The mass determination is reliable because the XMM–Newton tracking data allowed the astronomers to use the most robust method for ‘weighing’ a star, one that uses the gravitational physics devised by Isaac Newton in the 17th century. Most likely, the white dwarf has grown to its unusual mass by stealing gas from its companion star, a process known as accretion. At 1.3 solar masses, the white dwarf is now close to a dangerous limit.
When it grows larger than 1.4 solar masses, a white dwarf is thought to either explode, or collapse to form an even more compact object called a neutron star. The explosion of a white dwarf is the leading explanation for type Ia supernovae, bright events that are used as standard beacons by astronomers to measure the expansion of the Universe. Until now, astronomers have not been able to find an accreting white dwarf in a binary system where the mass could be determined so accurately.
Our descendants are in for quite a show. Thanks to XMM-Newton, we can already start looking forward to it.
Norbert Schartel | alfa
First Juno science results supported by University of Leicester's Jupiter 'forecast'
26.05.2017 | University of Leicester
Measured for the first time: Direction of light waves changed by quantum effect
24.05.2017 | Vienna University of Technology
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy