Brandon Q. Morris's Blog, page 14

How Earth rocks on the sea of space-time

A constant radiation in the microwave range, the background radiation, has long told cosmologists that something important happened 380,000 years after the Big Bang. At that time, electrons and protons recombined to form molecular hydrogen, so that space finally became transparent, allowing light to propagate. We can still measure the remnants of this light, shifted into the infrared.

But a lot happened shortly after the Big Bang. The very early universe was determined by time-varying scalar fie...

Luhman-16 B: The striped dwarf

Luhman-16 B is a brown dwarf – a star that was a little too small to actually become a star and ignite hydrogen fusion in its interior. Brown dwarfs are about the size of Jupiter, but typically dozens of times more massive. Luhman-16 B, along with its brother Luhman-16 A, is the closest to Earth of this type of celestial object. It is also the target of the “Majestic Dracht” in Proxima log 2.

Because of their nature – they do not glow – brown dwarfs are quite difficult to observe. Only with the ...

Intelligent life in the Milky Way is slowly dying out

Mankind is pretty late and pretty far out. That’s the conclusion of a study that statistically examines the development of intelligent life in the Milky Way. In it, the authors look at a whole range of factors that they think influence the evolution of intelligent life, such as the frequency of Sun-like stars hosting Earth-like planets, the frequency of civilization destroying supernovas, the length of time it takes for intelligent life to evolve (if conditions are right), and the tendency of ad...

Were the first black holes born in the form of baby universes?

Shortly after the Big Bang, the universe was still impenetrable. Its density was so high that a variation of only 50 percent – a coffee bean in a cake batter – would have been enough to produce a black hole immediately. The density was at least variable enough to let grow whole galaxies from the differences later. However, there seem to have been no “coffee beans” at that time – this is revealed today by the rather uniform cosmic background radiation.

Nevertheless, so-called promordial black hol...

Intergalactic gas filaments crisscross the universe

They crisscross the cosmos like cobwebs in a room that hasn’t seen a vacuum cleaner in a long time: In so-called filaments, unfathomably large, threadlike structures of hot gas that surround and connect galaxies and clusters of galaxies, astrophysicists have long suspected the previously hidden half of matter in our universe.

We owe our existence to a tiny error. After the big bang 13.8 billion years ago, the matter of the cosmos spread out in a gigantic gas cloud and was almost evenly distribut...

The most distant galaxy in the universe

How large is the universe? As large as the most distant object we can detect, might be one answer. But this is not quite true: The most distant visible object only marks the boundaries of the observable universe. This could be GN-z11. A team of astronomers used the Keck I telescope to measure the distance to this ancient galaxy. They found that GN-z11 is not only the oldest galaxy, but also the most distant. It is so far away that it actually defines the boundary of the observable universe itsel...

A lonely pair of gas giants that could never become a star

Star formation processes sometimes give rise to astronomical objects called brown dwarfs. They are smaller and colder than stars, and in the most extreme cases can have masses and temperatures down to those of exoplanets. Like stars, brown dwarfs often wander through space alone, but they can also appear in binary systems, where two brown dwarfs orbit each other and travel together in the galaxy.

Researchers led by Clémence Fontanive of the Center for Space and Habitability (CSH) at the Universi...

Richly covered menu in the Enceladus ocean

Life needs energy for its existence. The more extensive and diverse the supplies of a potential ecosystem are, the more stable the communities that develop there can be. For Saturn’s moon Enceladus, a new study now indicates that a diverse metabolic menu could support a potentially diverse microbial community in the liquid-water ocean beneath the moon’s icy skin.

Using data from NASA’s Cassini spacecraft, scientists at the Southwest Research Institute (SwRI) have modeled the chemical processes i...

Mysterious Signal from Proxima Centauri

“Towards the end of the 21st century, a call for help reaches Earth from the star closest to the sun, Proxima Centauri,” begins the blurb for “Proxima Rising.” The end of the century is still far off, but an apparently non-natural radio signal from the red dwarf has already reached us. The Guardian was the first to report it, and now the story is going around the world. The data in question was collected by the Parkes Observatory in Australia back on April 29, 2019.

“This is the most exciting si...

Spiders in Space: Light as a Substitute for Gravity

The University of Basel has just issued a very nice story in a press release. Its about spiders, and the following is probably only great for those who like the useful animals at least a little bit. But let the (translated) press release have its say.

On earth, spiders form asymmetrical webs, whose center is shifted towards the upper edge. In resting state the spiders sit upside down, because they can move faster in the direction of gravity towards freshly caught prey. But what do arachnids...