- Dr Michelle Thaller claims that ‘possible signs of live’ have been seen on Venus
- Venus is the hottest planet in our solar system at a scorching 475°C (900°F)
A planet that suffers scorching 475°C (900°F) temperatures beneath a thick acidic atmosphere may be the last place you’d expect alien life in our Solar System.
But one NASA scientist claims that extraterrestrials are most likely hiding on Venus amid conditions that are unbearable for humans.
The new theory was put forward by Dr Michelle Thaller, a research scientist at the US-based Goddard Space Flight Centre.
She says that ‘possible signs of life’ have already been seen within the carbon-dioxide filled atmosphere, adding that she was absolutely certain that life exists somewhere.
‘We see possible signs of life in the atmosphere of Venus,’ Dr Thaller said in an interview with The Sun.
NASA’s Dr Michelle Thaller claims that ‘possible signs of live’ have been seen on Venus
‘I never expected Venus. Venus is now one where we see something in the atmosphere that looks very much like it could be produced by bacteria.’
VENUS: THE BASICS
Venus, the second planet from the sun, is a rocky world about the same size and mass as the Earth.
However, its atmosphere is radically different to ours — being 96 per cent carbon dioxide and having a surface temperature of 867°F (464°C) and pressure 92 times that of on the Earth.
The inhospitable planet is swaddled in clouds of sulphuric acid that make the surface impossible to glimpse.
In the past, it has been suggested that Venus likely had oceans similar to Earth’s — but these would have vaporised as it underwent a runaway greenhouse effect.
The surface of Venus is a dry desertscape, which is periodically changed by volcanic activity.
Facts and Figures
Orbital period: 225 days
Surface area: 460.2 million km²
Distance from Sun: 108.2 million km
Length of day: 116d 18h 0m
Radius: 6,051.8 km
Mass: 4.867 × 10^24 kg (0.815 M⊕)
Venus is often described as ‘Earth’s twin’ due to its similar size and structure.
But their conditions couldn’t be further apart, as astronomers believe it would be impossible for humans to exist on Venus.
Positioned 67 million miles from the Sun, Venus is the hottest planet in our solar system, suffering temperatures that can even melt lead.
Its atmosphere – comprised of sulfuric acid and carbon dioxide – also adds to the inhospitable situation, sparking a ‘runaway greenhouse effect’ that prevents heat from escaping to the space beyond.
Despite this, scientists have long debated whether Venus’ clouds may host microbial lifeforms that can survive off sulfur, methane and iron.
Many theorise that photosynthesis is possible on the planet’s surface as Venus receives enough solar energy to penetrate through its thick clouds.
However, Professor Dominic Papineau, an astrobiologist at the University College of London, believes Dr Thaller’s views are ‘difficult to realistically hypothesise’.
Speaking to MailOnline, he explained: ‘For life-related chemical reactions to take place, liquid water is necessary. Hence, to find extraterrestrial life, we need to find liquid water, and to find extraterrestrial fossils requires looking for sedimentary rocks that were associated with liquid water in the past.
‘This make life on Venus today difficult to realistically hypothesise, because its surface is too hot, although Venus might have had liquid water in its past.
‘A problem with a possible fossil record on Venus however is the widespread volcanism that appears to have covered most of the surface in the last few hundreds of millions of years.’
Venus is the hottest planet in our solar system at a scorching 475°C (900°F)
Positioned 67 million miles from the Sun, Venus is the hottest planet in the solar system
Even still, both Professor Papineau and Dr Thaller agree that the icy moons of our solar system could also be sites of potential microbial life.
NASA suggests there are 290 ‘traditional Moons’ in our solar system – excluding 462 smaller asteroids and minor planets.
‘More likely we could find extraterrestrial life and/or fossil on Mars and in the icy moons of the outer solar system,’ Professor Papineau continued.
‘This is because liquid water exists on those planetary bodies, including within ice at the Martian south pole. Mars and icy moons also have a geological record that might preserve fossils.’
MailOnline has approached Dr Thaller for comment.
CARBON DIOXIDE AND SULPHURIC ACID DROPLETS FEATURE IN THE ATMOSPHERE OF VENUS
Venus’s atmosphere consists mainly of carbon dioxide, with clouds of sulphuric acid droplets.
The thick atmosphere traps the sun’s heat, resulting in surface temperatures higher than 470°C (880°F).
The atmosphere has many layers with different temperatures.
At the level where the clouds are, about 30 miles (50 km) up from the surface, it’s about the same temperature as on the surface of the Earth.
As Venus moves forward in its solar orbit while slowly rotating backwards on its axis, the top level of clouds zips around the planet every four Earth days.
They are driven by hurricane-force winds travelling at about 224 miles (360 km) per hour.
Atmospheric lightning bursts light up these quick-moving clouds.
Speeds within the clouds decrease with cloud height, and at the surface are estimated to be just a few miles (km) per hour.
On the ground, it would look like a very hazy, overcast day on Earth and the atmosphere is so heavy it would feel like you were one mile (1.6km) deep underwater.