The stars More than 8 solar masses will not end up white dwarf but it explodes supernovae SNII. Those with masses greater than 20/30 solar masses should not ejaculate enough issue in the blast so thatcollapse Gravity often gives a neutron starIt’s a stellar black hole. Those observed have masses between 5 and 15 solar masses. They refer to themselves in Milky Way Because of this material, they separate from a companion star, which forms an accretion disk, where the forces of viscous friction between the streams of matter spiral upward.star Compact, heat it up to the emission point X ray.
but according to astrophysicists Theorists who study the birth of neutron stars and stellar black holes, it may happen that the explosion asymmetric Thus the final compressed body is pushed as if Rocket. It is easy to calculate, as shown inStudied astrophysics from the famous house of William Pressfrom just the fact that it exploded in Binary system With a large loss of mass, the laws of mechanics also mean that a neutron star Or a newly formed stellar black hole being ejected massively Speedsometimes to the point of being able to free themselves from the gravitational pull of gravity Milky Way.
So astrophysicists think there must be a large number of single stellar black holes wandering or swooping through our galaxy. The number of these things can be roughly estimated 100 million But there are many uncertainties regarding the models that describe their birth, so it’s a little more accurate to say that this number is probably somewhere between 10 million and a billion. On the contrarydetermining this number will make it possible to sort these models and also to obtain information about the star and thus the chemical evolution of galaxies because they are rich in new heavy elements with each supernova explosion NS secondly.
But how do you detect these isolated black holes because they do not accumulate matter and therefore do not generate radiation indirectly?
Astronomers may have discovered the first floating black hole in the Milky Way, thanks to a technology called gravitational microlensing. For a fairly accurate French translation, click the white rectangle at the bottom right. The English translation should then appear. Then click on the nut to the right of the rectangle, then click on “Subtitles” and finally on “Translate automatically”. Choose “French”. © NASA’s Goddard Space Flight Center
Black hole makes stars shine
The general relativity gives the answer. expected to field gravity Which can eventually lead to bending a ray of light that is sent from a point very close to the surface of the events of the black hole, to the point where it falls in the direction of this black hole, and is also able to deflect the rays of stars in front of which this object can interfere with an observer so much that the environment Close to the black hole behaves like gravity lenswhich can temporarily increase brightness The star in front of which the black hole passes.
So astrophysicists have vowed to hunt down events that show microgravity using different tools, and two teams have just announced, Across Posted in Astrophysical Journal Letters and another in Astrophysical Journalthat they have finally found a candidate for a solitary stellar black hole in the Milky Way.
The two teams initially relied on monitoring campaigns with optical data coming from one sideGravitational Optical Lens Experiment (OGLE) on the other hand experience Microlens observations in astrophysics (Ministry Of Agriculture). OGLE uses a 1.3-meter telescope in Chile operated by the University of Warsaw, and the Ministry of Agriculture uses a 1.8-meter telescope in New Zealand operated by Osaka University. Since both micro-lens reconnaissance captured the same object, it Gate Two names: MOA-2011-BLG-191 and OGLE-2011-BLG-0462 or OB110462 for short.
The team is led by Cassie Lahm and Jessica Low In theUniversity of California at Berkeley The stellar black hole behind the event has been estimated to be between 2,280 and 6260 . light years Towards the center of the Milky Way, in Carina-Sagittarius spiral arm of our galaxy. It has also been estimated that the mass of an invisible compact body is between 1.6 and 4.4 times that of Sun (The larger the object, the stronger the effect of the lens, so we can measure its mass). So astrophysicists are cautious because it could be a neutron star or a black hole.
But the other team members led Kailash Sahu The Space Telescope Science Institute In Baltimore (Maryland) based on the same data but also on observations from the Hubble telescope, she is more confident in her assertions. As for its members, the compact object is about 5,153 light-years away and above all would have a mass about 7.1 times the mass of the Sun. This time, the object is too heavy to be a neutron star according to the theory of these objects, and the most likely hypothesis is that it is indeed a black hole and not a neutron star. Another strange star is still unknown.
Saho’s team estimates that the isolated black hole is moving through the galaxy at a staggering 160,000 kilometers per hour, fast enough to travel from Earth to Earth. the moon In less than three hours.
This discovery allows Astronomy scientists To estimate statistically that the closest isolated stellar-mass black hole to Earth could be close to 80 light-years away.
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