Previously, these steady ‘relativistic jets’ were only seen from black holes which form part of a black hole X-ray binary, a system containing a black hole orbited by a normal star which is so close that the black hole's gravity can peel off the outer part of the normal star and suck in its gas through an accretion disk or disk of matter.
A computer-generated visualisation of a black hole or neutron star X-ray binary system. Image produced using a visualisation tool provided by Rob Hynes of the Louisiana State University, USA.
Using the extremely sensitive infrared Spitzer Space Telescope recently launched by NASA, the team discovered one of these steady jets of matter coming from a neutron star (a super-dense type of dead star) in an X-ray binary system. For many years scientists have debated whether there was something unique to black holes that fuelled relativistic jets. It is now clear that the jets must be fuelled by something that both black holes and neutron stars share.
Neutron stars form in the death knells of massive stars, when the pressure at the centre of the star is so large that the electrons and protons of normal matter combine to form a star made almost entirely of neutrons. Not quite dense enough to be black holes, they have masses slightly larger than the Sun's, but diameters about the size of a city, making them as dense as the nuclei of atoms.
Dr Thomas Maccarone, of the University of Southampton, explains: ‘Jets of matter shot off by black holes are usually observed with a radio telescope which enables astronomers to isolate the jet from everything else in the system. However, observing a neutron star’s jets with a radio telescope would take many hours because the jets are very faint. The Spitzer Space Telescope sees light which is redder than the reddest colours visible by the human eye and also redder than the light given off by normal stars.’
Using the Spitzer Telescope, the researchers were therefore able to detect the faint jet of a particular neutron star, 4U 0614+091, in minutes even though it is located about 10,000 light-years away in the constellation Orion. This signal would have taken almost a day to detect on the most powerful radio telescopes on Earth. The Spitzer Telescope also helped the team infer details about the jet’s geometry. The team’s data indicates that the presence of an accretion disk and an intense gravitational field may be all that is needed to create and fuel a jet of matter.
Dr Maccarone continues: ‘For the past 25 years, astronomers have debated the importance of a black hole in jet production. By comparing the behaviour of the relativistic jets seen from neutron star X-ray binaries and from black hole X-ray binaries, astronomers have hoped to compare neutron stars and black holes directly and possibly to see whether these jets are extracting the black holes' rotational energy. This discovery blazes the trail for future studies which should help reveal the nature of relativistic jets.’
Sarah Watts | 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