When we think about whether there could be life elsewhere in the universe, we are often thinking about microbes on Mars or advanced civilizations from distant galaxies – but a recent discovery has scientists wondering whether there could be life on another planet close to Earth.
Scientists have discovered the gas phosphine in the atmosphere of our neighbor planet Venus. There are no known ways of producing this gas by a chemical reaction; only living bacteria can make it on Earth. Therefore, scientists believe that there could be life on Venus.
Venus is named after the Roman goddess of love. It has also been called the morning star because it often shines bright in the eastern sky before sunrise.
Humans have known about this planet for thousands of years, and in the Middle East, people worshipped it as a god. If you look at a modern Muslim mosque, you will still see the symbol of a crescent moon together with Venus.
In many ways, Venus is the twin planet of Earth. It is almost the same size, and the gravity on the surface is nearly the same. Since it is also in the solar system’s habitable zone, scientists long regarded it as the most promising place to look for alien life.
But in the first space mission into the Venusian atmosphere in 1967, scientists learned that the planet’s environment more closely resembled hell. Its surface temperature is a scorching hot 500° Fahrenheit, and it is raining sulfuric acid. No life as we know it can survive on the surface, so the scientists shifted their attention to Mars instead.
Gas from Bacteria?
Now, a team of scientists believe they have found phosphine in the upper atmosphere of Venus. Phosphine is a smelly and highly poisonous gas. On Earth, there is no known way to produce it through chemical reactions. Only certain types of anaerobic bacteria can create the gas.
Could this mean that there is life in the upper atmosphere of Venus? Scientists are encouraged because the temperature in that region is in the right range for life.
On Mars, they discovered methane. On Earth, this substance is produced in the guts of animals and by some bacteria. Maybe the methane on Mars comes from life? Scientists are not sure, but they say they have found ways nature can produce it chemically.
To check if there is life on Venus requires a space mission. A spacecraft must enter its atmosphere to collect gas samples. It then must successfully escape and return to Earth without being destroyed.
Unfortunately, that’s very difficult and expensive! At the moment, scientists and entrepreneurs like Elon Musk are more interested in going to Mars, so it may be a long time until we see a mission to Venus.