Astrophysics

May 29 2023

In search of the asymmetry of the universe

If the universe would be symmetrical, there would be neither you nor me nor anything else - except a lot of energy. Because then matter and antimatter, which must have existed at that time (symmetry presupposed) in identical quantity, would have annihilated each other shortly after the big bang. This did not happen. Matter retained the upper hand. So we know that the universe cannot be symmetrical. But why? The physics supplies us to it - still - keone clues. Astrophysicists have therefore been looking for visual traces for a long time, which might reveal something about the nature…

Where do the bubbles outside the Milky Way come from?

Astrophysics

May 16 2023

Where do the bubbles outside the Milky Way come from?

Back in 2020, astronomers made a striking discovery in the first complete sky map from the eRosita X-ray telescope aboard the SRG observatory: a huge circular structure of hot gas below the Milky Way plane that occupies most of the southern sky. A similar structure in the northern sky, called the "North Polar Spur," had been known for some time and was thought to have originated from an early supernova explosion. Taken together, the northern and southern structures instead both appear to emerge from the galactic center and are reminiscent of an hourglass in shape. These so-called eRosita bubbles…

Astrophysics

Apr 12 2023

A new picture of dark matter

We can't see it - but by observing its effects, we can still find out where it's hiding. We're talking about dark matter. Researchers at the Atacama Cosmology Telescope (ACT) have now used this principle to create a groundbreaking new image that shows the most detailed map of dark matter to date. It covers a quarter of the entire sky and extends deep into the cosmos. Moreover, it confirms - once again - Einstein's theory of how massive structures grow and bend light over the universe's lifetime of 13.8 billion years. "We've mapped the invisible dark matter across the entire…

Astrophysics

Apr 7 2023

The flattest explosion

An explosion the size of our solar system has stunned scientists because its shape - similar to an extremely flat disk - challenges everything we know about explosions in space. The observed explosion was a bright Fast Blue Optical Transient (FBOT) - an extremely rare type of explosion, much rarer than, say, supernovae. The first bright FBOT was discovered in 2018 and was nicknamed "the cow." Explosions of stars in the universe are almost always spherical, because the stars themselves are spherical. However, this explosion, which occurred 180 million light-years away, is the flattest ever discovered in space, with a…

Astrophysics

Mar 8 2023

The Way of the Water

The water that fills the earth's oceans, lakes and rivers has come a long way. It is initially formed in molecular clouds, which consist of 90 percent molecular hydrogen. When individual regions in these clouds condense into stars, it plays an important role in the formation of the protoplanetary disk. In the process, it is often transported as ice to their outer regions, from where it is later carried by comets to the inner planets. Cosmologists have already been able to document the first and the last section of this path well, but they have had measurement problems with…

Record: Most severe gamma eruption observed to date

Astrophysics

Oct 18 2022

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…

Astrophysics

Sep 28 2022

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

Sep 22 2022

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…)