Artist's impression of the possible closest black hole to Earth and its red giant star companion. Credit: Ohio State University / Lauren Fanfer

This Black Hole May Be Closest To Earth— 10 Things You Need To Know

Scientists even named the tiny object - "the Unicorn".

The dark companion of the red giant V723 Mon has become a candidate for the closest black hole to Earth. Astronomers came to this conclusion after analyzing the observations of the giant ground-based and space telescopes. The black hole has an estimated mass of 3.04 times the mass of the Sun, making it one of the lightest black holes known.

Studies of neutron stars and stellar-mass black holes in the Milky Way play a critical role in understanding the final evolution of massive stars and the mechanism of core-collapse.

However, to date, these types of compact objects are represented mainly by pulsars, magnetars, or binary systems, where a neutron star or black hole actively interacts with its companion.

To gain a better understanding of the properties of such objects, astronomers need to discover both single black holes and black holes in binary systems that are inactive.

10 things you need to know about the possible closest black hole to Earth and its red giant

1. A group of astronomers led by Tharindu Jayasinghe of Ohio State University announced the discovery of a candidate for the role of the closest known black hole to Earth.

2. It was discovered during the analysis of data from observations of ground-based and space telescopes for the bright red giant V723 Mon, which is located in the constellation Unicorn at a distance of 1,500 light-years from the Sun.

3. Earlier observations of this star made it possible to classify it as an eclipsing binary, while the idea of ​​a triple star system turned out to be untenable.

4. To understand the mass of V723 Mon, and, as a consequence, its nature, scientists carried out a number of simulations based on the light curves and data on the radial velocity variations of the giant.

5. The mass of V723 Mon has been estimated at one solar mass, and its radius at 24.9 times the solar radius.

6. On the other hand, the second object in the system was found to be much more impressive. Its mass was estimated at 3.04 ± 0.06 solar masses, which is more than the permissible mass of the white dwarf (1.44 solar masses) and the maximum known masses of neutron stars (2.01 and 2.14 the mass of the sun).

7. Thus, the simplest explanation for the observed properties of the V723 Mon system is that the companion of the red giant is a black hole, the mass of which lies in the gap between massive neutron stars and low-mass black holes.

8. In this case, the hole does not accrete the material of the star but slightly changes its shape due to tidal forces. You can see the artist’s impression of the red giant in the featured image above. Obviously, it has a distorted shape.

9. Scientists note that exotic scenarios such as a pair of neutron stars or a pair of “white dwarf – neutron star” can be used as an explanation for these observations.

10. To make more accurate conclusions, it is necessary to conduct multiwavelength observations of the system, but so far the dark companion V723 Mon has become a candidate for the closest black hole to Earth.

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Falk, D. (2021, April 29). Newfound black hole may be the closest to Earth.
Jayasinghe, T., Stanek, K., Thompson, T., Kochanek, C., Rowan, D., Vallely, P., . . . Murphy, S. (2021, March 26). A unicorn In Monoceros: THE $3M_odot$ dark companion to the BRIGHT, nearby red giant V723 mon is a NON-INTERACTING, mass-gap black hole candidate.
Wall, M. (2021, April 21). Tiny newfound ‘Unicorn’ is closest known black hole to Earth.

Written by Vladislav Tchakarov

Hello, my name is Vladislav and I am glad to have you here on Curiosmos. As a history student, I have a strong passion for history and science, and the opportunity to research and write in this field on a daily basis is a dream come true.

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