Hard Science Fiction

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…

Space

May 13 2023

Who polluted the globular clusters?

Globular clusters are very dense, spherical collections of stars with a radius of a dozen to a hundred light-years. They can contain up to a million stars and are found in all kinds of galaxies. There are about 180 of them in our galaxy. One of their great mysteries is the composition of the stars they contain. Although they were all born at the same time in the same gas cloud, the proportions of oxygen, nitrogen, sodium and aluminum, for example, vary from one star to another. A team from the Universities of Geneva (UNIGE) and Barcelona and the…

Life

Apr 19 2023

More life at the first stars?

The very first stars consisted only of hydrogen and helium - there were no other elements in the still young cosmos. When they died in gigantic explosions, they released what had accumulated in them: heavier elements, which were needed so that planets could form. The more heavy elements (cosmologists call them "metals," although chemically they aren't necessarily), the more planets can form, the better chance life has, right? Not quite. Whether life has a chance depends on more than just the composition of a celestial body. In fact, planets located in the habitable zones of metal-poor stars may be…

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…

Space

Apr 5 2023

85,000 volcanoes on Venus

You are planning a trip to Venus? Then you'd better avoid the numerous volcanoes there. This works better with good map material, as it is now finally available: Planetologists Paul Byrne and Rebecca Hahn from Washington University have counted 85,000 volcanoes on our neighboring planet Venus - and entered them on a map for the first time. The accompanying database is publicly available. "This work is the most comprehensive map of all volcanic structures on Venus ever produced," says Byrne, associate professor of earth and planetary sciences at Washington University in St. Louis. "It provides researchers with an enormously…

Space

Mar 22 2023

Why ‘Oumuamua accelerated

Comet (?) 'Oumuamua is the first known object formed outside the solar system that astronomers could observe on its way through our solar system. Its nature is still not conclusively explained - at least for some researchers. What we do know: It has not shown any radiation. Measurements in this regard are so accurate that even a cell phone transmitting on the object would have been noticed. But 'Oumuamua also shows a small non-gravitational acceleration. So it didn't move exactly as would have been expected based on mass and velocity. This is not unusual for comets. They typically release…