The first extragalactic black hole

In the world of black hole researchers, there is a group led by Tomer Shenar that, so far, has mostly demonstrated the non-existence of black holes previously announced by other teams.
As Shenar himself recalled, however,

For the first time, our group has come together to discuss the discovery of a black hole, instead of eliminating one.

We are talking about a black hole found inside the Tarantula Nebula, which is part of the Large Magellanic Cloud, one of the satellite galaxies of the Milky Way.
In particular, this black hole, of stellar mass, is of the "dormant" type, that is, it emits very low levels of X radiation, which are the radiations with which black holes are generally discovered.
This happens because the black hole interacts very little with its surroundings.
Another interesting aspect of the discovery is the absence of any trace of the star that generated the black hole.

[It] appears to have completely collapsed, with no sign of a previous explosion.

This black hole, the first extragalactic, was discovered orbiting a massive star thanks to six years of observations at ESO's Very Large Telescope.

Fluorine in the early universe

Using ALMA (Atacama Large Millimeter/submillimeter Array), a team of astronomers has detected fluorine in a galaxy far, far away: its light reached us after a journey of over 12 billion years.
What we see of the NGP-190387 galaxy is a large cloud of gas crystallized at the time when the universe was only 1.4 billion years old. And since stars shed chemical elements into their surroundings only when they reach the end of their life, which generally ends explosively, the detection of fluorine in the gases of NGP-190387 implies that the stars in the galaxy must have lived relatively short lives. In particular these characteristics are possessed by the Wolf–Rayet stars.
Furthermore, the levels of fluorine in NGP-190387 (the first galaxy after the Milky Way where this chemical element was observed) are comparable to those of our galaxy, with the difference that the latter is older than a dozen and more than billions of years compared to NGP-190387.

We have shown that Wolf–Rayet stars, which are among the most massive stars known and can explode violently as they reach the end of their lives, help us, in a way, to maintain good dental health!

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- Maximilien Franco from the University of Hertfordshire in the UK

(ESO's press release)

42: A family portrait

No, this is not the towel day, but what ESO released yesterday is undoubtedly something quite useful for any space tourist: a series of 42 detailed images of the largest asteroids in the solar system.
The main asteroid belt, located just beyond the orbit of Mars, is made up of rocky objects of various sizes, reaching up to 200 km in diameter, without forgetting the largest of all, Ceres and Vesta, respectively 940 and 520 kilometers in diameter. The family portrait of the 42 asteroids was made using the Very Large Telescope:

Supermassive web hole

With the help of ESO’s Very Large Telescope (VLT), astronomers have found six galaxies lying around a supermassive black hole when the Universe was less than a billion years old. This is the first time such a close grouping has been seen so soon after the Big Bang and the finding helps us better understand how supermassive black holes, one of which exists at the centre of our Milky Way, formed and grew to their enormous sizes so quickly. It supports the theory that black holes can grow rapidly within large, web-like structures which contain plenty of gas to fuel them.

The location of the supermassive black hole is in the Sextans' constellation.
Sextans is a small and dark constellation straddling the celestial equator and located near Leo. Introduced in 1687 by Johannes Hevelius, thanks to its equatorial position, the Sextant is visible from most of the Earth's surface.
The main stars are not particularly bright, but with a particularly clean sky it is possible to identify them even with the naked eye, in particular Alpha Sextantis, a blue-white giant with a magnitude of 4.48, and 35 Sextantis, an orange double star, the whose main star has a magnitude of 5.79. Also noteworthy there are the white Gamma Sextantis (magnitude 5.07) and the blue Beta Sextantis (magnitude 5.08).

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(via ESO)

A Day in the life of ESO

the video about the #ESO50years celebration day posted by @ulaulaman

In order to celebrate the 50th anniversary of the ESO, it was realized a streaming with a lot of talk by some ESO's researchers. After the celebration day, there was released the video of the weblive:

In the image a screenshot from Fernando Papat's talk with a quotation by Giorgio de Santillana