Life | Hard Science Fiction

May 4 2022

More life on younger planets

Nowadays we know more than 5000 exoplanets. Among them are some that are similar in size to Earth, are also made of rock, and orbit their star in an area that astrobiologists call the habitable zone. Habitable here refers to life as we know it, which is based on water and carbon and therefore also requires liquid water on the surface. Which of these candidates should we look at first, for example with the new James Webb telescope, which will also be able to determine the atmospheric composition of distant worlds? Where are the chances of finding life the…

Life

Jan 3 2021

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 advanced civilizations to self-destruct. The researchers incorporated these factors, with varying values, into a simulation of the Milky…

Life

Sep 25 2020

Signs of life from the clouds of Venus?

Our hot sister planet, Venus, basically has no potential for life on its surface – the pressure and temperature are much too high. Nevertheless, in “The Clouds of Venus,” a team from NASA made an interesting discovery. I was reminded of this when I read a new press release from Cardiff University. Astronomer Jane Greaves and her colleagues have been analyzing Venus’s atmosphere for years and stumbled across an interesting substance: phosphane (older, but chemically incorrect name: phosphine). On Earth, phosphane, a compound of phosphorus and hydrogen (PH3), is a gas produced predominantly by anaerobic biological sources. The conditions on…

How many civilizations are there in the Milky Way?

Life

Jul 2 2020

How many civilizations are there in the Milky Way?

Are there other thinking creatures in the universe? Researchers recently determined that life should be at least relatively common. In terms of intelligence, however, the results, which were based on an analysis of its development on Earth, were less clear. A new article published in the Astrophysical Journal has come to somewhat more encouraging results. Astrophysicist Tom Westby, one of the authors, explains his group’s approach: “The classic method for estimating the number of intelligent civilizations relies on making guesses of values relating to life. Opinions about such matters, however, vary quite substantially. Our new study simplifies these assumptions using…

Life

Jun 21 2020

How common is life in the universe?

The question is basically unanswerable. The well-known Drake equation feigns a certain degree of precision but suffers from the fact that it is nearly impossible to reach agreement on values for any of its seven factors. Right now, we have only one example for intelligent life, and for us to draw conclusions for the entire universe from just our own existence would, indeed, be very human, but would be scientifically problematic. There is, however, an alternative. We could ask what the likelihood would be for life to develop on Earth if we turned back the clock and started over from…

Astrophysics

May 13 2020

Life in a hydrogen-rich atmosphere

The exoplanet K2-18b, about 124 light-years from Earth, is a kind of mini-Neptune, as astronomers discovered this past year. It is seven to ten times heavier than Earth and its radius is 2.7 times larger. K2-18b orbits its host star, a red dwarf, once every 33 days. Thus, it is located in its star’s habitable zone. For astronomers, however, it has one other special noteworthy feature: hydrogen, helium, and water vapor have been detected in its atmosphere. In the media, K2-18b has even been described as “Earth 2.0,” which it very definitively is not. The researchers who studied it…

Life

Apr 10 2020

There’s life, even hundreds of meters below the ocean floor

On Earth, there’s life everywhere – well, almost everywhere, one exception being the geothermal fields in the Ethiopian region of Dallol. Researchers have detected at least primitive bacteria almost everywhere: on the highest mountains, in hydrothermal vents, in corrosive lakes, and even deep in the oceans. Scientists have even found traces of life hundreds of meters below the bottom of the sea, as reported in an article in the magazine, Communications Biology. In their research, the scientists looked, in particular, at the Earth’s upper oceanic crust. It consists of basaltic lava, which has been deposited there from the depths…

Life

Mar 17 2020

Bad news for life on Titan – or not?

So that life as we know it can emerge, it must be able to differentiate itself somehow from its environment. Therefore, every cell needs a shell that allows nutrients to pass through it from the outside, but nevertheless protects the cell’s insides from the outside world. On Earth, cell membranes perform this function and are made from lipids, hydrocarbon compounds that include, among other things, fatty acids. On Saturn’s moon, Titan, it is much too cold, at an average temperature of -180 °C, for the formation of lipids. But there is a different class of substances there that astrobiologists…