Is there life on Venus? Scientists detect traces of phosphine and ammonia in the planet’s clouds and say they could come from microbes

With its boiling temperatures and acidic clouds, it is one of the most formidable worlds in our solar system.

But exciting new findings suggest that life could exist on Venus, the second planet from the Sun.

Researchers have confirmed traces of ammonia and phosphine in the planet’s clouds: two potential “biomarkers” indicative of life.

On Earth, both compounds are produced during the decomposition of organic matter, such as plants and animals.

Since there are currently no other known natural processes for its production on Venus, it could be being produced by something unknown to scientists.

This follows the original detection of phosphine in the clouds of Venus in 2020, although the findings were soon debunked by skeptics.

The new findings were presented at the National Astronomy Meeting 2024 at the University of Hull on Wednesday.

Professor Jane Greaves, an astronomer at Cardiff University and author of the findings, said ammonia has been seen before in the solar system, but also on the gas giant planets Jupiter and Saturn.

“It’s natural there because its gas is mostly hydrogen,” he told MailOnline.

“It is much rarer on rocky planets like Earth or Venus.”

Ammonia is a naturally occurring, colorless, poisonous gas produced primarily by the anaerobic decomposition of plant and animal matter.

Professor Greaves and his colleagues detected the gas in the clouds of Venus using the Green Bank Telescope in West Virginia.

The giant 2.3-acre antenna detects faint radio waves raining down on us from objects in space.

“In simple terms, the Green Bank telescope captures a rainbow of light, except it does so in radio light,” said Professor Greaves.

‘When there is a lack of light, it is because a molecule has absorbed it and we use the exact wavelength to identify the molecule.’

Ammonia was detected in the upper parts of the planet’s clouds, where it is too cold for life to exist.

However, there is a possibility that ammonia is also found in the deeper, warmer areas of the clouds and then rises to the upper parts.

This is what the researchers will try to establish next.

Meanwhile, phosphine was discovered by a team led by Professor Greaves and Dr Dave Clements at Imperial College London’s Department of Physics, studying data from the James Clerk Maxwell Telescope in Hawaii.

Phosphine, a colorless gas that smells like garlic or rotting fish, is produced naturally on Earth by certain microorganisms in the absence of oxygen.

It can also be released in small quantities from the decomposition of organic matter or synthesized industrially in chemical plants.

Dr. Clements stressed that the detection of both gases on Venus is not evidence that life exists there and it is unknown what processes are emitting them.

“Most likely it is some chemical process that we currently don’t understand and know nothing about,” he told MailOnline.

‘But phosphine has been proposed as a biomarker for exoplanets (planets outside our solar system), and on Earth it is only found associated with life, so life is also a possibility.

“At this point we just don’t know: more observations and more laboratory and theoretical work are needed to understand what’s going on, and perhaps future missions to Venus will help as well.”

Venus is known as Earth’s “evil twin” because it is also rocky and about the same size, but its average surface temperature is a scorching 870 °F (465 °C).

Thanks to its dense atmosphere, Venus is even hotter than the planet Mercury, although the latter orbits closer to the Sun.

The rocky sphere is not only inhospitable but also barren, with a surface hot enough to melt lead and toxic clouds of sulfuric acid.

Because the clouds are so acidic, the phosphine would break down very quickly and would therefore need to be continually replenished.

However, it is generally believed in the astronomical community that the planet was not always such a hostile place.

Perhaps as recently as 700 million years ago, Venus likely had oceans similar to Earth’s and could have supported life as we know it today.

But those oceans disappeared when our neighbouring planet suffered a “runaway greenhouse effect” – a dramatic rise in temperatures.

It was in 2020 that scientists revealed traces of phosphine gas in the planet’s clouds that they said could have come from microbes.

At the time, Professor Greaves and his colleagues observed Venus using the James Clerk Maxwell Telescope at the Mauna Kea Observatory in Hawaii and the Atacama Large Millimeter/submillimeter Array in Chile.

They detected a so-called “spectral signature” that is unique to phosphine and estimated that the gas is present in Venus’s clouds at an abundance of about 20 parts per billion.

However, other scientists claimed not to be able to find the same signal, and members of Greaves’ team admitted a calibration error and downplayed the strength of their claims.

Now, using the James Clerk Maxwell Telescope again, Dr. Clements has been able to find phosphine again and believes it could be destroyed by sunlight during the day.

‘Ultraviolet rays in sunlight break up the molecule, which may explain why phosphine has been found in some observations while not in others,’ said Dr Clements.

Dr Robert Massey, deputy chief executive of the Royal Astronomical Society, who was not involved in the research, called the findings “very exciting”.

“But it should be noted that the results are only preliminary and more work is needed to learn more about the presence of these two potential biomarkers in the clouds of Venus,” he told MailOnline.

‘However, it is fascinating to think that these detections could indicate possible signs of life or some unknown chemical processes.

“It will be interesting to see what further research uncovers in the coming months and years.”