Life

A place on Earth where everything’s dead Life

A place on Earth where everything’s dead

So far, the Earth is the only place in the universe where life has been proven to exist. But even on our planet, there are places that life cannot survive. The geothermal fields in the Ethiopian region of Dallol are one of these places. Near the Danakil Depression in northeastern Ethiopia, close to the border with Eritrea, a volcanic explosion in 1926 formed a crater with a diameter of 30 meters (98 ft), exposing hot salt springs. The emerging water is 70°C (158°F) and extremely acidic with a pH value below 1. At the same time, the air temperature…
Life might also exist on cold planets Life

Life might also exist on cold planets

Our Earth has already lived through several ice ages, during which the oceans were covered with ice all the way down to the equator – so-called Snowball eras. Life on our planet has survived all these times; primarily due to one reason: at the time, life existed only in the oceans, and the depths of the oceans still offered good conditions for life. What would have happened if life had already made its way onto land? That was the basis of a study done by Canadian researchers. Snowball Earths result basically when the percentage of carbon dioxide (CO2) in…
Traces of life in a meteorite from Mars Life

Traces of life in a meteorite from Mars

ALH-77005 has already been through a lot. The lump of stone, which weighs around one pound, was ripped from the surface of Mars 178 million years ago by the impact of a bigger meteorite. The force of the impact flung it into space. Through no fault of its own, ALH-77005 was then put on a course to Earth, where it arrived three million years later. It was bigger at the time, but its entry into the Earth’s thick atmosphere would have broken it apart. A lump of brown-gray stone, weighing 483 grams and measuring 9.5 cm x 7.5 cm…
Where are we most likely to find signs of extraterrestrial life? Life

Where are we most likely to find signs of extraterrestrial life?

Today, astronomers know that most stars develop a planetary system during the course of their life. It is estimated that the total number of planets exceeds the total number of stars. On average, each star has between one and two planets. With its 200 billion stars, the Milky Way therefore might have around 300 billion planets. Of course, there is a huge amount of variability in these planets. There are gas giants that rotate on very tight orbits and are almost as hot as their host star. There are icy planets on the distant outskirts of their systems, like…
Did life come from outer space? Life

Did life come from outer space?

How did the building blocks of life come about on Earth? So far, science has not given a very exact answer to this question. The most important experiment on this question was conducted in 1952 by Stanley Miller and Harold Urey at the University of Chicago. They mixed together simple chemical substances of a hypothetical young Earth atmosphere – water, methane, ammonia, hydrogen, and carbon monoxide, but no oxygen – and exposed this mixture to electrical discharges that were meant to replicate the energy supplied from lightning in thunderstorms. The result: after some time, organic molecules were produced. At…