Hard Science Fiction

Apr 13 2022

Fast growing black hole discovered

Astronomers have known for a while that the centers of most galaxies are home to supermassive black holes. With ever-improving methods of investigation, they have been able to trace these giants far back into the past. They must have existed as early as 750 million years after the Big Bang. This raises one of the biggest mysteries in astronomy today: How could these supermassive black holes, which weigh millions to billions of times the mass of the Sun, grow so large so quickly? Current theories hold that supermassive black holes begin their lives in the dust-shrouded cores of galaxies…

Space

Apr 11 2022

Surprising cold on Neptune

Neptune, the outermost planet of our solar system, does not belong to the ice giants with its neighbor Uranus for nothing. The enormous distance to our central star ensures that the temperature out there falls below minus 200 degrees Celsius (-238 °F). Exactly how warm it gets depends, of course, on its current position in orbit. However, distinct seasons are not really to be expected: Neptune has an almost circular orbit, so it only moves away from or comes close to the Sun minimally, and at the same time it stands on this orbit with a very low axial…

Space

Apr 2 2022

4 mile high ice volcanoes on Pluto

The exploration of the dwarf planet Pluto is divided into two eras: Before the arrival of NASA's New Horizons probe, the celestial body was thought to be an icy, unspectacular Kuiper Belt object. But New Horizons then delivered images and data that sent astronomers into raptures. The composition of Pluto's surface shows that there are a variety of ages here, from relatively old, heavily cratered regions to very young surfaces with few to no impact craters. One of the regions with very few impact craters is dominated by huge mountains with humpbacked flanks not found anywhere else in the…

Peas, blueberries and grapes – not every galaxy is like the Milky Way

Space

Apr 1 2022

Peas, blueberries and grapes – not every galaxy is like the Milky Way

Elliptical galaxies, spiral galaxies, barred spiral galaxies, you've probably heard of them. But did you know that there are types of galaxies named after green peas, blueberries, or purple grapes? When a group of amateurs within the "Galaxy Zoo," a project conducted by citizen scientists, classified galaxies observed by the Sloan Digital Sky Survey (SDSS) by color and morphology, they found 251 very special galaxies that didn't easily fit into the known galaxy types. These galaxies, which looked round and dense like beans and appeared green on digital images, were later named "Green Pea Galaxies." (more…)

Space

Mar 30 2022

Earendel: The farthest star

Far-away stars, however luminous, cannot be photographed individually even with the best space-based telescopes. But this would be extremely interesting for researchers, because with increasing distance we are entering the early days of the universe, about which we still know too little. But with a bit of luck, the universe itself is helping astronomers - by placing powerful galaxies in such a convenient way that they amplify the light of a star that is actually much too distant - in this case in the form of the galaxy cluster WHL0137-08. For example, the Hubble Space Telescope recently succeeded in…

Space

Mar 23 2022

How old is the Milky Way?

Our home galaxy contains up to 400 billion stars, and to cross it would take 200,000 years even at the speed of light. Such a huge object (which is rather average in cosmic comparison) does not come into being overnight. The Milky Way was actually born relatively early - at a time when the universe was still quite young. But when exactly, and how do you measure that? Quite simply, if you want to know how old a forest is, you determine the age of its trees. The stars of the Milky Way do not have annual rings, but…

Astrophysics

Mar 19 2022

When the universe began to boil

How did the supermassive black holes come into being, which today are gigantic sentinels in the center of many galaxies? Initially, one proceeded from the obvious: The giants grew by accreting other matter or consuming black holes, that is, by merging with them. Step by step, from small to medium to giant. But this concept has a couple of problems. First, we have not yet been able to detect the necessary intermediate stages. They should still exist, but so far we have only found small black holes - or the really big ones. Problem number 2 is that there…

Even on smaller icy moons, the chances for life on the ocean floor are good

Enceladus

Mar 3 2022

Even on smaller icy moons, the chances for life on the ocean floor are good

The fact that astrobiologists have such high hopes for icy moons like Enceladus or Europa is not only due to the oceans they have been able to detect under their ice crusts, but also to the fact that they are geologically active worlds. The culprits are the giant parent planets Saturn and Jupiter, respectively, which really knead the moons with their gravitational force. This creates heat, which keeps the water in their hidden oceans liquid and relatively warm. The water in turn dissolves from the underlying rock layers what potential life could need. Energy is also released in the…