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They might have come across a wandering black hole

We cannot directly observe black holes, only by the effects they create, for example, if they have a companion from which material is taken. However, it is assumed that our galaxy may be full of small, mostly lonely ones, so they can only be seen in special cases with black holes. The Review of the Hubble Space Telescope website It resembles the density of a black hole as if a naval fleet were being squeezed into a basketball. Usually, a single black hole is an object with multiple solar masses, whose strong gravity bends the space around it, and the path of starlight is also deflected as a result of this effect, allowing its detection.

Astronomers say hundreds of millions of these black holes could make their way through hundreds of billions of stars in our galaxy, but discovering them presents an astonishing challenge. However, it may have succeeded recently, thanks to the fact that the star’s light passing behind the supposed black hole has been amplified and deflected for a short time by gravity. The researchers were able to detect this through long-term observational and measurement work, thanks to Hubble’s excellent resolution. A black hole usually deflects a star’s light, blocking other objects with excellent gravitational lensing effects.

For the first time, with a series of observations lasting about 6 years, we were able to prove that a single black hole migrates through our galaxy, interstellar space, by measuring the mass of an invisible object. So far, we’ve only come across such small black holes with a few star weights through companion stars, so the real special thing now is.

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Using the method of microgravity, the change in the star’s light behind the black hole showed the existence and nature of the black hole.

Source: NASA, ESA, STScI, Joseph Olmsted

The black hole now discovered is located in the arms of the Milky Way’s Carina-Sagittarius, about 5,000 light-years away, but the discovery statistically means that the closest may be only 80 light-years away (our nearest star, Proxima Centauri, is just 80 light-years away. 4 light years). Similar solitary black holes are made up of giant stars that weigh approx. 20 solar masses, after completing the formation of a constellation in a supernova explosion, its remnants are compressed to become extremely dense due to their gravity. Because the explosion is not perfectly symmetrical, the resulting black hole will blast into the galaxy to gain momentum.

Circled is the star that brightened during the observation period due to the supposed black hole.

Source: STScI / NASA / ESA

Many ground-based telescopes monitor the star-rich central region of the Milky Way for signs of a black hole and then use Hubble to conduct follow-up investigations to confirm – or refute – the hypothesis. Currently, the stray has been found using this method, STScI, which also operates Hubble, and a team of researchers from the University of Berkeley was investigating one potential site, and although there were slight differences in their results, both teams found the black hole stray.

2011-2017 star shines and fades in Hubble shot due to alleged black hole,

Source: NASA, European Space Agency, Kailash Sahu (STScI), with image processing by Joseph DePasquale of STScI

The microgravity method is as follows: a distant object, for example we try to observe an exoplanet by waiting for another object of greater mass to pass between the target and the Earth. The gravity of a massive intermediate object deflects and amplifies the light of a distant target object, making the invisible visible. Now, however, astronomers were not interested in the object behind them, but rather in the object that caused the lens effect. Of the nearly 30,000 cases examined so far, a black hole has a very unique fingerprint. The black hole’s intense gravity stretched the star’s light for more than 200 days, and the possibility that the star’s color didn’t change – another star might change it, the two stars’ light in front of each other – but that hasn’t happened now. In our case, the elongated light of the star can be detected in the background for 270 days.

With the help of Hubble, it is also possible to determine the mass and motion of the black hole, and to make precise measurements of how much star light the black hole dissipates. One research group says it has 7 solar masses, which is clearly in the range of a black hole, while the other research group says it has 1.6-4.4 solar masses, in this case a larger mass means a black hole and a smaller mass means a neutron star. The researchers estimated the black hole’s speed at 160,000 kilometers per hour, which is faster than other stars in that region of our galaxy (roughly equivalent to reaching the moon in 3 hours).

Whether the object is a black hole or a neutron star, it is sure to be the first sight to discover a single, dark, star-sized object in this way.

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