Brandon Q. Morris's Blog, page 3

Conditions for life in the Enceladus ocean increasingly certain

Saturn’s moon plays a special role in my books. Therefore, I am always very happy when there is news about possible life in the moon’s ice ocean. Like the following. A team of scientists has apparently discovered new evidence for an important building block for life in the subsurface ocean of Saturn’s moon Enceladus. Their model calculations suggest that Enceladus’ ocean should be relatively rich in dissolved phosphorus, an essential ingredient for life.

“Enceladus is one of the most important t...

Gas bubble chases around core of Milky Way

Astronomers have discovered a hot gas bubble rotating clockwise around the black hole Sagittarius A* – the core of our Galaxy. However, this bubble has not been found directly, but via an accompanying phenomenon: flares in the X-ray range, which have been detected again and again, starting from the black hole Sgr A*. Since nothing can leave the black hole itself, a phenomenon in the immediate vicinity must be responsible – the gas bubble.

“We suspect that we are dealing with a hot gas bubble or...

What do black holes have to do with the Big Bang?

A few milliseconds after the Big Bang, there was apparent chaos in the universe. While particles merged and broke apart again, incredibly strong pressure waves ran through the early cosmos. They pressed the particles so tightly against each other that black holes were formed, today called primordial black holes by astrophysicists.

What impact did these black holes have on the formation of the first stars, about a hundred million years later? The Standard Model assumes that black holes at that ti...

What saved Earth from the fate of Mars?

Three billion years ago, liquid water existed on Mars as well as on Earth. Today, this is only the case on our home planet. Why is that? Mars no longer has such a strong magnetic field as the Earth. Therefore the solar wind can take the atmosphere better there than here. The magnetic field is generated in the outer core of the Earth, where liquid iron rotates (this is called a “geodynamo”). About 565 million years ago, however, the strength of the magnetic field decreased to 10 percent of its pr...

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...

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 galaxi...

Worlds quite different from Earth could also harbor life

Are our ideas of the habitable zones around a star too Earth-centric? Of course. We’ve only found one example of life in the universe so far, so we all draw conclusions. But there are alternatives, as researchers from the University of Bern and the University of Zurich have just reported in a study published in the journal Nature Astronomy. According to the study, favorable conditions could even prevail for billions of years on planets that barely resemble our home planet.

“One of the reasons wa...

What NASA is up to in the clouds of Venus

In nine years (2031), our hot neighboring planet Venus will be visited by NASA’s DAVINCI mission (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging). In a paper, the scientists and engineers involved have now explained what the probe is supposed to do. As its name suggests, it is primarily concerned with the planet’s dense atmosphere, in which – unlike on the hot surface – conditions are expected to be favorable even for life. Davinci is therefore primarily a flying chem...

Why Uranus and Neptune are colored differently

Actually, Uranus and Neptune, the two outer planets of the solar system, are quite similar. Known as the “ice giants,” the planets have similar masses (14.5 to 17 Earth masses), sizes (51,000 to 49,000 km at the equator), and atmospheric compositions (hydrogen at around 80%, helium around 15%, methane about 2%) – and yet they differ significantly in appearance. In the visible wavelength range, Neptune has a rich, deep blue hue, while Uranus has a much paler cyan hue. Astronomers have now found a...

How heavy are the stars?

R136a1 is currently the heaviest known star. It weighs as much as 265 suns. Most stars, however, are much smaller and lighter – down to about one tenth of the mass of the sun. Celestial bodies that have accumulated too little gas cannot ignite nuclear fusion and remain brown dwarfs. Supergiants like R136a1, on the other hand, glow intensely but die young. How heavy are the stars of the universe on average? This is described by the so-called primordial mass function. It says that heavy stars are ...