The world is watching the outbreak: a new black hole has been discovered in the Galaxy

About the event of a galactic scale, to which the attention of all astrophysicists of the world has been riveted for more than a week, scientists report. In the course of planned observations of the region of the Galactic Center – the core, which once gave rise to the formation of our galactic system, a new black hole was discovered. The brightness of the glow of the object Swift J1727.8-1613 is one of the three largest events over the past 10 years.

Russian astrophysicist, Doctor of Physical and Mathematical Sciences, Deputy Director for Research at the Space Research Institute of the Russian Academy of Sciences (IKI RAS) Alexander Lutovinov spoke about the discovery:

– This new object, named Swift J1727.8-1613, appeared about a week ago. Since August 24th, it has become the brightest object currently observed in X-rays. Naturally, almost all the world’s observatories immediately pointed towards the center of our Galaxy, where the flare occurred.

Help “MK”.

The Galactic Center is a relatively small region at the center of our Galaxy, which is located 8.5 kiloparsecs from our solar system in the direction of the constellation Sagittarius. The radius of the Center is about 1000 parsecs (pc).

1 pc is equal to 3.2616 light years.

1 light year is equal to 9.46 trillion km. To overcome such a distance, moving at a constant speed of 100 km / h, it will take about 11 million years, and with the speed of the ISS (8 km / s), it will take 37.5 thousand years to overcome 1 light year.

It is noteworthy that the flare itself was registered by the SWIFT observatories (after which the new object got its name) and INTEGRAL. Moreover, the latter at that moment was conducting observations of the region of the center of the Galaxy at the request of Russian scientists from the IKI RAS. Soon, the appearance of a new object in the sky was confirmed by other observatories, including ground-based ones, which conduct observations in the optical range. The extreme brightness of the source in X-rays was confirmed on August 27 by the results of observations by the ART-XC telescope named after. Mikhail Pavlinsky of the Russian observatory Spektr-RG. According to scientists, they temporarily interrupted all previous ART-XC programs and began to observe the brightest event in the sky.

– How did you manage to notice this outbreak first? Did you expect it and therefore brought the INTEGRAL to this area in advance? I ask Alexander Lutovinov.

– Not certainly in that way. The INTEGRAL observatory carried out routine observations of the region of the Galactic Center at the request of Academician Rashid Alievich Sunyaev. And at some point, a trigger was triggered about the appearance of a bright event in the field of view. Approximately at the same time, a similar trigger worked at the SWIFT observatory, after which information about the event was automatically distributed among scientists. The value and uniqueness of the data obtained by the INTEGRAL observatory lies in the fact that they contain information about the first hours of the development of an X-ray flare – in fact, we see its growth in hard X-ray in real time.

– What is this glow?

– According to preliminary data, this is a black hole, unknown before, which is located in our Galaxy, and which very quickly became extremely bright. For example, the ART-XC telescope registered approximately 30 million photons from its side and the so-called quasi-periodic oscillations (oscillations or flickers of the X-ray emission of an astronomical object at certain frequencies – Auth.).

Why do these flickers occur?

– They are associated with the rotation and precession (change in the direction of the axis of rotation – Ed.) of the internal orbits of the accretion disk – a ring structure that appears around a black hole as a result of the fall of stellar matter onto it.

“So you sort of caught a black hole eating breakfast?”

– Yes, a black hole, which usually does not glow, reveals itself only in this way, at the moment of “eating” the matter of a nearby star. This happens after certain evolutionary processes on the star, when it suddenly begins to overflow the so-called Roche lobe (this is the area where the equilibrium point between two astronomical objects is located), and the substance begins to flow into the black hole.

– How far is the black hole discovered in this way from us, is its size known?

– There are no exact estimates of the mass of this object yet, as well as the exact distance, its lower limit is estimated at about 10,000 light years (about 3 kiloparsecs).

What similar event can be compared with this event?

There are several dozen known black holes in our galaxy. However, by the strength of the outbreak of the latter, not everyone can compare with it. Perhaps Swift J1727.8-1613 is one of the three brightest X-ray events in the last decade. In any case, we intend to continue monitoring it and, hopefully, will further refine many of its parameters.

Help “MK”. The INTEGRAL observatory is an orbital observatory designed to study galactic and extragalactic objects in the hard X-ray and gamma-ray range. This is a joint project of the European Space Agency, Roscosmos and NASA.