Astrophysics

When the fog dissolves Astrophysics

When the fog dissolves

In winter the fog sometimes does not dissolve the whole day. In space, planetary nebulae usually exist for many millennia, because they are star shells that have been ejected by their stars at the end of their lifetime. In the case of the Stingray Nebula, which was first catalogued in 1976 and is located 18,000 light years from Earth, this seems to be an exception. Images of the system taken by the Hubble Space Telescope in 2016 show a nebula that has drastically lost brightness and changed shape compared to Hubble images from 1996. Light blue gas shells near…
Milky Way’s Family Tree Astrophysics

Milky Way’s Family Tree

From small to large: this is one of the possible ways in which structures are created in the universe. Galaxies like our Milky Way are formed when several small predecessor objects join together. But what exactly did the Milky Way form from? An international team of astrophysicists led by Dr. Diederik Kruijssen from the Center for Astronomy at the University of Heidelberg has succeeded in reconstructing the merging history of our home galaxy and creating its family tree. To this end, the researchers analyzed the properties of globular star clusters orbiting the Milky Way. Globular clusters are dense groups…
How the universe heats up Astrophysics

How the universe heats up

Shortly after the Big Bang, in the Planck era, the universe was about 1032 Kelvin hot. Afterwards it expanded rapidly and cooled down as the energy spread over an ever larger space. By and large, this process should continue as long as the universe expands - an end to the expansion is not yet in sight, on the contrary. But there is a process that counteracts this cooling - at least temporarily. It is easy to understand. When 10,000 people go home from a football stadium, the mood cools down initially as the density of people decreases. But when…
Why the brain and the cosmos are structurally similar Astrophysics

Why the brain and the cosmos are structurally similar

The human brain has a volume of a about one liter (0,26 gallons, man: 1.27 l, woman: 1.13 l), i.e. one cubic decimeter or 0.001 cubic meter. The universe, on the other hand, has a volume of 2.3 million billion trillion cubic light years. Obviously, this is a huge difference of over 30 orders of magnitude. Nevertheless, both structures, the network of galaxies that criss-crosses the universe and the neural network in the brain, have surprising similarities, as Franco Vazza (astrophysicist at the University of Bologna) and Alberto Feletti (neurosurgeon at the University of Verona) note in a paper…
In search of dark matter with pendulums Astrophysics

In search of dark matter with pendulums

Current experiments that search for dark matter are mostly based on the idea that dark matter should somehow show up, i.e. by interacting with normal matter. Now, however, the only thing we really know about this important part of the universe is that an interaction with normal matter occurs via gravity. This is what first made researchers realize that dark matter exists. Is it perhaps because the search has so far been fruitless? Then a method could help, which researchers of the NIST and their colleagues presented now. "Our proposal is based purely on gravitational coupling, the only coupling…
Massive black hole turns star in solar size into spaghetti Astrophysics

Massive black hole turns star in solar size into spaghetti

About 215 million years ago the fate of a star was fulfilled: It was swallowed by a black hole with a million solar masses. The death struggle dragged on for a whole month. Meanwhile, the dying star was bidding farewell, a high-energy flare that emitted enough energy in the X-ray range alone to accelerate the Earth to one percent of the speed of light. This flare, called AT2019qiz and registered on Earth in 2019, was a gift to terrestrial astronomers. It is the first star death of this kind that was discovered so close to the Earth (although 215…
Galaxies in a cosmic spider web made of dark matter Astrophysics

Galaxies in a cosmic spider web made of dark matter

Using ESO's Very Large Telescope (VLT), astronomers have found six galaxies orbiting a supermassive black hole when the universe was less than a billion years old. The galaxies are in a kind of cosmic "spider web" of gas that covers an area 300 times the size of the Milky Way. "The filaments of the cosmic web are like spider web threads," explains Marco Mignoli, astronomer at the National Institute of Astrophysics (INAF) in Bologna, Italy, and lead author of the new research published today in Astronomy & Astrophysics. "The galaxies grow where the filaments cross, and gas flows -…
Black holes reveal themselves in the X-ray spectrum Astrophysics

Black holes reveal themselves in the X-ray spectrum

Black holes are the remnant of stars with more than eight solar masses. Everything we know points to their existence – the theory of relativity, cosmology, etc. And yet, only one supermassive black hole – with a mass of more than 6 billion solar masses – has been “photographed” to date with the help of surrounding radiation in the radio wavelength range. But stellar-mass black holes have not yet been seen. That’s why scientists are pleased that an international team of astrophysicists has now found distinct signatures of the event horizon of black holes that clearly distinguish them from…