Space

Watching a planet grow Space

Watching a planet grow

Astronomers usually detect exoplanets based on irregularities in the glow of the parent star. Although more than 4,000 exoplanets have been cataloged to date, only 15 have been imaged directly by telescopes. Even in their best photos, the planets are just dots, simply because they are so far away and quite small. A new technique from the Hubble team is now expected to help image planets directly. The researchers have used it to catch a rare glimpse of a Jupiter-sized planet, still forming, that feeds on material surrounding a young star. They report it in the Astronomical Journal. "We…
Brown dwarfs at the speed limit Space

Brown dwarfs at the speed limit

Brown dwarfs are formed when a newborn star does not have enough mass to ignite the nuclear fusion of hydrogen. This is their essential difference to giant gas planets - brown dwarfs form quasi first and in the center of the system, gas giants follow later. As central objects of their system, brown dwarfs naturally inherit the rotation of the protostellar cloud. But some of them apparently give extra gas later. Astronomers at Western University in Canada have now discovered three brown dwarfs that spin faster than any previously found, coming close to the theoretical maximum speed. The astronomers…
Two pairs of quasars in the early universe Astrophysics

Two pairs of quasars in the early universe

Quasars are loners. This is not because they do not get along with their colleagues, but has something to do with their nature. They are nuclei of active galaxies. And every galaxy has only one nucleus. Billions of stars can rotate badly around several cores. Nevertheless, astronomers have now found two quasar pairs at a distance of about ten billion light years as they report in Nature Astronomy. (more…)
Basic structure of the cosmos pictured for the first time Astrophysics

Basic structure of the cosmos pictured for the first time

Stars group together to form galaxies. Galaxies form galaxy clusters. These form superclusters, between which vast, largely empty regions extend, the voids. All superclusters are connected by a honeycomb-like basic structure, the "cosmic web", which consists of filamentary gas structures of hydrogen. That these filaments must exist has been known for some time. On the one hand, they are known from simulations based on theories of the structure of the universe, which predict such a basic structure. On the other hand, they become visible when energetic quasars illuminate them like car headlights illuminating the nebula. However, the regions thus…
What a volcano would look like on a metal world Space

What a volcano would look like on a metal world

On Earth it rains water, on Titan liquid methane comes from the sky. On some planets it rains iron or even diamonds. Such differences also exist in volcanology. On Ceres, researchers have discovered ice volcanoes, while terrestrial volcanoes spew cinders of liquid rock. On the asteroid Psyche, which consists primarily of metal, there may once have been iron volcanoes. Perhaps elsewhere, too. But what would such volcanoes look like? Knowing that is important for detecting them on distant celestial bodies. A team of researchers led by Arianna Soldati of North Carolina State University has studied this in a very…
Quasar transmits from the early days of the universe Astrophysics

Quasar transmits from the early days of the universe

In the 1950s, astronomers discovered radio sources to which point-like, i.e. star-like objects could be assigned in the visible light range. Until then, whole galaxies had been identified as radio sources. The findings were called "quasi-stellar objects", or quasars for short. Later, however, researchers realized that quasars are embedded in galaxies after all, and in fact constitute their active nuclei radiating in many wavelength ranges. That they had been seen only as point sources was simply because they are very, very distant. In fact, they are the most distant objects in the universe that we can observe. This is…
Super Venus in our cosmic neighborhood Space

Super Venus in our cosmic neighborhood

Wolf 437, also called Gliese 486, is a red dwarf fairly close to the Sun - just 26 light-years away. What makes it interesting is a planet that astronomers now present in Science. Gliese 486 b moves around its parent star in a circular orbit within 1.5 days and at a distance of only 2.5 million kilometers (Earth: 150 million kilometers). Since its rotation around its own axis always takes the same time, the planet always turns the same side to its sun - similar to the moon to the earth. Although the star Gliese 486 is much fainter and…
When a star rips apart … Astrophysics

When a star rips apart …

... a muon deep under the ice of Antarctica creates a trace in a gigantic detector. The muon was created because a high-energy neutrino interacted with an atom in the detector. The neutrino began its journey about 700 million years ago, around the time the first animals evolved on Earth. That's the travel time it took for the particle to get from the distant, unnamed galaxy (cataloged as 2MASX J20570298+1412165) in the constellation of The Dolphin to Earth. It occurred as a result of "AT2019dsg." This is what astronomers call an event in which a star was ripped apart…