The black hole closest to Earth does not exist, it is actually a binary star system

In 2020, scientists announced the discovery of the black hole closest to the earth so far, a three-body system HR 6819 composed of 1,120 light-years away and two other bright stars, but follow-up observations pointed out that black holes do not exist, and HR 6819 is only composed of 2 stars binary system. Higher-resolution observations now show that there is indeed no black hole in the HR 6819 system, but two stars that are in the “stellar blood-sucking” stage orbiting at close range.

The year before last, when astronomers used the FEROS spectrometer on the MPG/ESO telescope at La Silla Observatory in Chile to conduct an in-depth study of the HR 6819 binary system in the existing database, they found that the system may be a triple star with a black hole. Metasystem, in which two stars revolve around each other in the form of binary stars, and the black hole orbits the pair of stars in a distant place, with a revolution period of about 40 days, in which the mass of the black hole is about 4 times that of the sun.

However, a few months later, another team conducted a second analysis based on the same data and found that the HR 6819 system was actually just a binary star system, with both stars orbiting for 40 days and no black hole at the center.

To find out, the two teams decided to work together to collect new observations using the Very Large Telescope (VLT) and the Very Large Telescope Interferometer (VLTI), resulting in higher-resolution images from the VLT that showed the two stars were only a short distance away. At one-third the distance between Earth and the sun, there are no bright companion stars orbiting further out, and no black holes.

As for why astronomers misunderstood the existence of black holes in the system in the first place? The team believes the best explanation is that they captured a phenomenon shortly after one of the stars sucked up the atmosphere of the companion star, sometimes referred to as a “stellar blood-sucking” process, which is relatively difficult to detect during the stage of stellar evolution, and further study of HR 6819 will reveal Uncover how the stellar blood-feeding process affects the evolution of massive stars.

Although the “disappearing” black hole is disappointing, the current black hole closest to Earth may become the one 1,500 light-years away that forms a binary system with π1 Grus, but astronomers believe that one day they will discover the number of stars lurking in the Milky Way. Tens of millions, even hundreds of millions of small black holes.

The backside of exoplanets is full of surprises, and WASP-121b will rain liquid gemstones at night

The weather on the backside of exoplanets can be unbelievably wonderful, such as the hot exoplanet WASP-121b 850 light-years away, which accumulates metallic iron clouds, rains liquid gemstones, and blows 17,703 kilometers per hour on the backside. of strong winds.

WASP-121b is an exothermal Jupiter nearly 2 times larger than Jupiter. It is 850 light-years away from Earth. It was first discovered in 2015 and has one of the shortest planetary orbits ever detected, orbiting the star in 30 hours. WASP-121b is also tidally locked by the parent star, so the sun-facing (daytime) side facing the parent star is so hot that the atmospheric molecules are almost disintegrating.

Previous studies have found that WASP-121b has stratosphere and water vapor, and includes heavy metals such as iron, magnesium, chromium, and vanadium, which escape into space in the form of gas on the sunny side without precedent in history. According to the new study by the MIT team, the scientists further mapped the dramatic temperature changes from the sun side to the back side and tracked how water circulates in WASP-121b.

Earth’s water evaporates, condenses into clouds, and rains in constant cycles; but the WASP-121b molecule cycles much more strongly. The researchers pointed out that molecules will decompose into atoms at high temperature on the sunny side, and the temperature of the back (night) side of WASP-121b is half lower than that of the other side. and reassemble into molecules.

This cycle, while not forming clouds of water, creates clouds of metallic iron and corundum—the minerals that make up rubies and sapphires—and drops a strange rain of liquid gemstones before the clouds leave the night.

Other astronomers have scheduled the James Webb Space Telescope to observe WASP-121b later this year, hoping to map changes in carbon monoxide in addition to water vapor. MIT astronomer Mikal-Evans said this would be the first time measuring carbon-containing molecules in an exoplanet’s atmosphere, and analyzing atmospheric carbon and oxygen levels could provide clues to where such planets formed.

The new paper is published in the journal Nature Astronomy.

With a diameter of 250 million light-years, the interior is dark, how terrible is the Bode constellation?

We often say that the matter in the universe is uniformly distributed in all spaces after the big bang. With the passage of time, because of the imbalance between the expansion speed of the universe and the size relationship between celestial galaxies, its gravitational effect on matter is also unbalanced. It is different, so there are more blank spaces in the cosmic space.

But in general, the distribution of matter and galaxies in the cosmic space is relatively balanced, and there will be no particularly large deviations.

However, scientists have found a very large “hole” in the northeast direction of the Virgo galaxy in the northern sky. The hole is about 250 million light-years in diameter and about 700 million light-years away from Earth.

At this location, which is more than 2,500 times larger than the Milky Way’s 100,000 light-years, there are so few stars in it that it becomes a huge blank area, which scientists have named the “Boes Void”.

Boes Hollow
As one of the largest known voids in the universe, there are so few galaxies in the Boes Void that it is almost impossible to find a single galaxy until an average of 10 million light-years.

We can compare it like this: the diameter of the Milky Way is only about 1/2500 of that of the constellation Boe, and in terms of volume, the constellation Boo can hold tens of millions of galaxies. In this “small” Milky Way galaxy, there are 100-400 billion stars alone, but in this huge constellation Boes, scientists have discovered here in the more than ten years since its discovery in 1981 to 1997. The number of galaxies is less than 60. The gap is so large that Boes is sometimes referred to as the “super-void”.

According to the scientists’ calculation of the distribution of galaxies in other spaces, it is reasonable that there should be at least 2,000 galaxies in the constellation Boo, but the reality is quite rare, and the distances between them are quite far, on average, almost 2000 galaxies. 10 million light years. Why is the Shepherd’s seat so empty?

Because galaxies are too rare, there is a view that the original matter in the Boes constellation void may have been taken away by other surrounding matter with greater gravitational force in the early stage of its formation. Later, the universe expanded and the galaxies moved away faster than the speed of light. The Booness hole is naturally getting bigger and bigger.

From the distribution of some sparse galaxies, it has been suggested that the super-large void in Boes may be formed by the combination of multiple small voids. Others believe that the constellation of Boes is not empty and is filled with dark matter and dark energy.

The formation of cosmic voids
Scientists have discovered some (dark) blue regions from the microwave background radiation distribution map that studies the distribution of heat in the universe after the Big Bang. They are the “holes” of the energy-poor and extremely sparsely distributed universe.

There are not many “voids” in the universe, and Boes is just one of them. The largest cosmic void discovered by human beings is far more terrifying than the size of the constellation Shepherd. Its diameter can reach 1.8 billion light-years. It is simply an invincible giant, known as a “super void”.

These voids do not mean that they exist in a complete vacuum, but in terms of the total distribution of matter in the universe, the matter here is 20% or more less than that in other regions, and the density is extremely low. When there are voids in the universe, where no galaxies are found, there are naturally no stars, planets and other matter. Because no celestial body can exist independently of a galaxy.

That is, to some extent, we can understand the void of the universe as a dark region of “nothing”, including the Boes Void.

Maybe some people think that the gap between the galaxies is too big? Where did so many empty words come from?

According to scientists’ research on cosmic voids, about 10,000 galaxies have disappeared from the universe. The area where they were originally also lost energy due to the “invisibility” of matter, and gradually cooled to become the low temperature region of the universe. The blue part of the above-mentioned cosmic microwave background radiation map, the darker the color, the lower the temperature, there is almost no matter here.

But in this case, scientists also don’t know where these stars go, or why the galaxies are so far away from this area. It has been suggested that if dark matter is to be blamed, then the formation of voids may be related to the activity of dark matter.

So is there any other possibility besides dark matter? Some scientists have proposed another possibility: the expansion of advanced civilizations in the universe. How should this be understood?

What advanced civilization did?
Regarding the speculation and exploration of cosmic civilization, the world has never lacked reservations about advanced civilizations other than humans. After all, the universe currently has no boundaries for human beings, and it is not completely certain whether there will be civilizations that we do not know about.

According to the level of Kardashev civilization, civilization in the universe should have three major stages: planetary energy utilization, star system energy utilization, and (galaxy) parent galaxy energy utilization.

Based on this understanding, we can make a bold guess: Could the voids in the universe be caused by advanced civilizations that utilize the energy of other galaxies in the universe?

In order to better develop their own civilization, these advanced civilizations take, store, utilize and consume the energy of the galaxy, leaving only a void with nothing. When the energy of the nearby galaxy is completely absorbed, the advanced civilization will The range of galactic energy sources will continue to increase, and the voids will become larger and larger.

Such speculation is not completely unreasonable, but it is a bit exaggerated. The energy utilization of a star system is exaggerated enough. How advanced civilization must it consume tens of millions of galaxy energy? According to this consumption, how long will the galaxy energy in the universe be enough for these civilizations to consume?

Obviously, not many people agree with this view.

Other astronomers believe that these cold regions of space are evidence of cosmic cycles. It’s just that the theory of cosmic circulation is still in the stage of speculation and confirmation, and which view is more informative, we have to wait for more astronomical observations.