Space

Rocky planets from the planet factory Space

Rocky planets from the planet factory

Why do rocky planets in a given star system usually look relatively similar? A new theory developed by Konstantin Batygin, professor of planetary science at Caltech, along with Alessandro Morbidelli of the Observatoire de la Côte d'Azur in France, may explain. "With the increase in exoplanet observations over the past decade, it has become clear that the standard theory of planet formation needs to be revised, starting with the basics. We need a theory that can explain both the formation of terrestrial planets in our solar system and the formation of self-similar systems of super-Earths, many of which have…
Why Venus died the heat death – and the Earth did not Life

Why Venus died the heat death – and the Earth did not

Venus, Earth's hot little sister, was probably once habitable, too, a long time ago. It basically orbits in the habitable zone. Surface temperatures of 450 degrees would actually not be expected there, were it not for the dense CO2 atmosphere that heats up the planet with its greenhouse effect. But why did this happen on Venus - and not on Earth so far? Volcanism is probably to blame, as researchers show in a new paper. According to the paper, volcanic activity that lasted hundreds to thousands of centuries and ejected massive amounts of material may have helped transform Venus…
Neutron star light – or something completely different? Space

Neutron star light – or something completely different?

Stars that are at least about three times heavier than the sun suffer a spectacular end. They manage to use all elements up to iron as fuel in different shells in their interior. Their core, which is only 10,000 kilometers across, then usually consists of iron and heavier elements. What happens to the dying star now depends mainly on this core. When it exceeds the Chandrasekhar limit of 1.44 solar masses, its matter can no longer resist its own gravity - and the star collapses into a neutron star. (more…)
Fluffy planet orbits a cool red dwarf star Space

Fluffy planet orbits a cool red dwarf star

Astronomers using the 3.5-meter WIYN telescope at Kitt Peak National Observatory in Arizona have observed an unusual Jupiter-like planet in orbit around a cool red dwarf star. This planet, designated TOI-3757 b, is located about 580 light-years from Earth in the constellation Auriga, the charioteer, and is the lowest density planet ever discovered around a red dwarf star. Researchers estimate that its average density is equivalent to that of a marshmallow. Red dwarf stars are the smallest and faintest members of the so-called main sequence stars - stars that convert hydrogen to helium at a uniform rate in their…
The ashes of the very first stars Astrophysics

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…
News from the cosmic origin of life Life

News from the cosmic origin of life

Nitriles, a class of organic molecules with a cyano group, i.e. a carbon atom bonded to a nitrogen atom via an unsaturated triple bond, are usually toxic. Yet, paradoxically, they are also an important precursor for molecules that are essential for life - namely, ribonucleic acid (RNA). Astrobiologists already knew that complex molecules are surprisingly common even in space, which is hostile to life. Now, a team of researchers from Spain, Japan, Chile, Italy and the United States has shown that a wide range of nitriles occur in interstellar space in the molecular cloud G+0.693-0.027, near the center of…
What’s hiding near Andromeda? Space

What’s hiding near Andromeda?

First there was an amateur astronomer: Giuseppe Donatiello found an interesting "spot" in the Dark Energy Camera data on the 4-meter Víctor M. Blanco telescope. Then, using the larger 8.1-meter Gemini North telescope, the professionals took a closer look and confirmed that the object, then named Pegasus V, was an ultra-faint dwarf galaxy on the edge of the Andromeda Galaxy. The observations revealed that the galaxy appears to be extremely poor in heavier elements compared to similar dwarf galaxies, which means that it is very old and probably represents a fossil of the first galaxies in the universe. In…