Uploaded February 2014 | Updated September 2026, 21 hours ago
http://www.astropage.eu/index_news.php?id=1400 In tödlicher Umarmung - Millisekundenpulsare verdampfen ihre Begleitsterne
Black widow spiders and their Australian cousins, known as redbacks, are notorious for an unsettling tendency to kill and devour their male partners. Astronomers have noted similar behavior among two rare breeds of binary system that contain rapidly spinning neutron stars, also known as pulsars.
The essential features of black widow and redback binaries are that they place a normal but very low-mass star in close proximity to a millisecond pulsar, which has disastrous consequences for the star. Black widow systems contain stars that are both physically smaller and of much lower mass than those found in redbacks.
So far, astronomers have found at least 18 black widows and nine redbacks within the Milky Way, and additional members of each class have been discovered within the dense globular star clusters that orbit our galaxy.
One black widow system, named PSR J1311-3430 and discovered in 2012, sets the record for the tightest orbit of its class and contains one of the heaviest neutron stars known. The pulsar's featherweight companion, which is only a dozen or so times the mass of Jupiter and just 60 percent of its size, completes an orbit every 93 minutes - less time than it takes to watch most movies.
The side of the star facing the pulsar is heated to more than 21,000 degrees Fahrenheit (nearly 12,000 C), or more than twice as hot as the sun's surface. Recent studies allow a range of values extending down to 2 solar masses for the pulsar, making it one of the most massive neutron stars known.
NASA's Goddard Space Flight Center
Greenbank Telescope image credit: NRAO/AUI
http://www.astropage.eu/index_news.php?id=1400 In tödlicher Umarmung - Millisekundenpulsare verdampfen ihre Begleitsterne
Black widow spiders and their Australian cousins, known as redbacks, are notorious for an unsettling tendency to kill and devour their male partners. Astronomers have noted similar behavior among two rare breeds of binary system that contain rapidly spinning neutron stars, also known as pulsars.
The essential features of black widow and redback binaries are that they place a normal but very low-mass star in close proximity to a millisecond pulsar, which has disastrous consequences for the star. Black widow systems contain stars that are both physically smaller and of much lower mass than those found in redbacks.
So far, astronomers have found at least 18 black widows and nine redbacks within the Milky Way, and additional members of each class have been discovered within the dense globular star clusters that orbit our galaxy.
One black widow system, named PSR J1311-3430 and discovered in 2012, sets the record for the tightest orbit of its class and contains one of the heaviest neutron stars known. The pulsar's featherweight companion, which is only a dozen or so times the mass of Jupiter and just 60 percent of its size, completes an orbit every 93 minutes - less time than it takes to watch most movies.
The side of the star facing the pulsar is heated to more than 21,000 degrees Fahrenheit (nearly 12,000 C), or more than twice as hot as the sun's surface. Recent studies allow a range of values extending down to 2 solar masses for the pulsar, making it one of the most massive neutron stars known.
NASA's Goddard Space Flight Center
Greenbank Telescope image credit: NRAO/AUI


![XJ1500+0154 Animations
Every so often, an object will pass too close to a black hole and be ripped apart by its intense gravitational forces. As the object, such as a star, approaches the danger zone of the black hole, its stellar debris is flung outward at high speeds, while the stars material falls towards the black hole. This in-falling material becomes hotter and hotter until it generates a signature outburst of X-rays. Astronomers call these tidal disruption events, or TDEs, and they can be used to better understand how black holes grow and affect their environments.
While astronomers have seen multiple examples of TDEs in recent years, a new discovery stands out among the rest. Using data from three X-ray telescopes: Chandra, Swift, and XMM-Newton, researchers have found a TDE that has lasted about ten years, much longer than other events. What could cause this decade-long meal by the black hole? There are a couple of possibilities. The first is that this black hole, located in a galaxy about 1.8 billion light years from Earth, completely shredded the largest star astronomers have known to be destroyed in a TDE. The other, also intriguing, possibility is that in previous TDEs the star wasnt completely ripped apart, but in this event it was. While astronomers continue to study this source and look for others like it, we are reminded just how amazing black holes can be.
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(Credit: X-ray: NASA/CXC/UNH/D.Lin et al, Optical: CFHT, Illustration: NASA/CXC/M.Weiss) XJ1500+0154 Animations](https://i.ytimg.com/vi/WXanjtSw63E/mqdefault.jpg)







