Astrophysics

Record: Most severe gamma eruption observed to date Astrophysics

Record: Most severe gamma eruption observed to date

A cosmic explosion of gigantic proportions kept astronomers on tenterhooks in mid-October - the closest and possibly most energetic gamma-ray burst (GRB) ever observed. The GRB, designated GRB 221009A, occurred at a distance of about 2.4 billion light-years in the direction of the constellation Arrow. It was first detected on the morning of Oct. 9 by X-ray and gamma-ray space telescopes, including NASA's Fermi Gamma-ray Space Telescope, the Neil Gehrels Swift Observatory and the Wind spacecraft. As news of this discovery quickly spread, two teams of astronomers worked closely with Gemini South staff to obtain the earliest possible observations…
The ashes of the very first stars Astrophysics

The ashes of the very first stars

The universe was just 100 million years old when the first stars already flared up. Very early on, dark matter amplified inhomogeneities in the structure of the universe in such a way that there were areas with a higher concentration of hydrogen. This clumped together, and as still happens today, a star was formed. With our sun these very first cosmic beacons, which are called "Population III" today, are hardly comparable. They must have consisted mainly of hydrogen and helium - already because there were no other elements at all in the early universe. This is how these stars should…
Gas bubble chases around core of Milky Way Astrophysics

Gas bubble chases around core of Milky Way

Astronomers have discovered a hot gas bubble rotating clockwise around the black hole Sagittarius A* - the core of our Galaxy. However, this bubble has not been found directly, but via an accompanying phenomenon: flares in the X-ray range, which have been detected again and again, starting from the black hole Sgr A*. Since nothing can leave the black hole itself, a phenomenon in the immediate vicinity must be responsible - the gas bubble. (more…)
What do black holes have to do with the Big Bang? Astrophysics

What do black holes have to do with the Big Bang?

A few milliseconds after the Big Bang, there was apparent chaos in the universe. While particles merged and broke apart again, incredibly strong pressure waves ran through the early cosmos. They pressed the particles so tightly against each other that black holes were formed, today called primordial black holes by astrophysicists. What impact did these black holes have on the formation of the first stars, about a hundred million years later? The Standard Model assumes that black holes at that time favored the formation of halo-like structures through their gravitational pull as condensation nuclei, similar to how clouds are formed…
How heavy are the stars? Astrophysics

How heavy are the stars?

R136a1 is currently the heaviest known star. It weighs as much as 265 suns. Most stars, however, are much smaller and lighter - down to about one tenth of the mass of the sun. Celestial bodies that have accumulated too little gas cannot ignite nuclear fusion and remain brown dwarfs. Supergiants like R136a1, on the other hand, glow intensely but die young. How heavy are the stars of the universe on average? This is described by the so-called primordial mass function. It says that heavy stars are much rarer than light ones. So the universe is likely to be…
Does a hidden mirror universe influence our world? Astrophysics

Does a hidden mirror universe influence our world?

One of the fundamental parameters of our universe is the Hubble constant H0. It indicates the speed with which distant objects move away from us and thus determines the fate of the entire universe. Today we know that it is not a constant in the strict sense, since H0 changes with time. However, science has a fundamental problem with it. Depending on how it is measured, its value differs. The difference between the measurement methods even grows the more precise the measurements are. If H0 is calculated from the standard model of cosmology (Lambda Cold Dark Matter, ΛCDM), the…
Topology is everywhere Astrophysics

Topology is everywhere

Topology is an important branch of mathematics. It deals with such properties of mathematical forms that are preserved under constant deformation (i.e. without tearing or cutting them). Topology is also the basis of the plot in my upcoming Möbius trilogy. The strange artifact in question is a topological construct. As an author, I am naturally delighted when an international team of researchers has now discovered and published in the journal Science that almost all materials in nature have at least one topological state. This contradicts the forty-year-old assumption that topological materials are rare and esoteric. "Topology is everywhere" is…
Black hole winds are no longer what they used to be Astrophysics

Black hole winds are no longer what they used to be

In the early times of the universe, black holes in the centers of active galaxies grew much faster than today. Only in this way it can be explained that 500 to thousand million years after the big bang there were already such huge black holes. Today, however, things look different - the black holes at the centers are evolving in parallel with their host galaxies. When and why did this change occur? That's what a study led by three researchers from Italy's National Institute of Astrophysics (INAF) in Trieste has found, published in the journal Nature. The work is…