Archive

Archive for August 14, 2013

Magnetic Star Reveals Its Hidden Power

August 14, 2013 Leave a comment

Artist's impression. Credit: ESA/ATG Medialab

Artist’s impression. Credit: ESA/ATG Medialab

A team of astronomers including two researchers from UCL’s Mullard Space Science Laboratory has made the first ever measurement of the magnetic field at a specific spot on the surface of a magnetar. Magnetars are a type of neutron star, the dense and compact core of a giant star which has blasted away its outer layers in a supernova explosion.

Magnetars have among the strongest magnetic fields in the Universe. Until now, only their large scale magnetic field had been measured. However, using a new technique and observations of a magnetar in X-rays, the astronomers have now revealed a strong, localised surface magnetic field on one.

Magnetars are very puzzling neutron stars. Astronomers discovered them through their unusual behaviour when observed in X-ray wavelengths, including sudden outbursts of radiation and occasional giant flares. These peculiar features of magnetars are caused by the evolution, dissipation and decay of their super-strong magnetic fields, which are hundreds or thousands of times more intense than those of the more common type of neutron stars, the radio pulsars.

Full Story: http://www.ucl.ac.uk/maps-faculty/maps-news-publication/maps1323
Also: http://www.esa.int/Our_Activities/Space_Science/Mysterious_magnetar_boasts_one_of_strongest_magnetic_fields_in_Universe

Advertisements

Newly Found Pulsar Helps Astronomers Explore Milky Way’s Mysterious Core

August 14, 2013 Leave a comment

Artist's conception. Credit: Bill Saxton, NRAO/AUI/NSF

Artist’s conception. Credit: Bill Saxton, NRAO/AUI/NSF

Astronomers have made an important measurement of the magnetic field emanating from a swirling disk of material surrounding the black hole at the center of our Milky Way Galaxy. The measurement, made by observing a recently-discovered pulsar, is providing them with a powerful new tool for studying the mysterious region at the core of our home galaxy.

The Milky Way’s central black hole is some four million times more massive than the Sun. Black holes, concentrations of mass so dense that not even light can escape them, can pull in material from their surroundings. That material usually forms a swirling disk around the black hole, with material falling from the outer portion of the disk inward until it is sucked into the black hole itself.

Such disks concentrate not only the matter pulled into them but also the magnetic fields associated with that matter, forming a giant, twisting magnetic field that is thought to propel some of the matter back outward along its poles in superfast “jets.”

The region near the black hole is obscured from visible-light observations by gas and dust, and is an exotic, extreme environment still little-understood by astronomers. The magnetic field in the central portion of the region is an important component that affects other phenomena.

Full Story: http://www.nrao.edu/pr/2013/magfield/#caption
Also: http://www.astron.nl/about-astron/press-public/news/new-radio-pulsar-explores-feeding-habits-milky-way’s-massive-black-ho
Also: http://www.astron.nl/about-astron/press-public/news/new-radio-pulsar-explores-feeding-habits-milky-way’s-massive-black-ho