Are we alone in the universe ? Is Earth the only life-sustaining planet ? Has life ever existed on neighboring planets ? These are questions that have plagued the human race since time immemorial.
An international team of scientists has recently discovered the existence of phosphine in the atmosphere of Venus, causing quite the stir, potentially being a sign of life (among many other explanations). What is even more interesting is that researchers are perplexed as to how phosphine got there.
Earth’s evil twin
The Evening star has always shone brightly in our night sky but is there could be other life forms staring back. Venus, our nearest neighbor and sister planet, is named after the Roman goddess of love and beauty. It is of similar size and mass to Earth. What is even more interesting is that researchers are perplexed as to how phosphine got there. On Earth, phosphine is only made industrially or by microbes that flourish in oxygen-free environments.
Paradoxically, the rocky planet is as inhospitable as they come. Venus has sulphuric acid rains, which almost certainly have the potential to destroy any living organic molecules, not protected by a cell. Our DNA would be rapidly destroyed by such conditions. Some bacteria can survive in such acidic conditions.
Venus also a suffocating CO2 atmosphere possible, making it the last holiday destination of choice for humans. If you thought press-ups in our world were bad, Venus also has a surface atmospheric pressure up to 100 times greater than Earth. Based on our understanding of life on Earth, Venus is about the last planet in the Solar System that we would expect to find living organisms.
Does phosphine equal life ?
The presence of phosphine on Venus could be signs of aerial alien biology. Or perhaps, the biosphere of Venus is strengthening to one day provide the basis for life. Or the presence of the chemical could be unexpected and unexplained biochemistry or some geological process on the lifeless planet that we are yet to understand.
Two detections of phosphine in the atmosphere of Venus have occurred nearly two years apart, once in 2017, and the second in 2019. Whatever is producing the compound is ongoing. What is sure is that the discovery reaffirms the mysteries of the universe that humanity has yet to explain. Conditions higher up in the atmosphere of Venus are less temperature and toxic than the planet’s surface, and the pressure is less crushing. The upper atmosphere of Venus is much milder. In fact, temperatures are low enough to enable droplets of water to form, which, in theory, could be a basis for life.
The ingredients for life
There is still a great mystery surrounding the origin of life on earth with multiple competing theories. What most of the scientific world is sure of is that there are a set of environmental conditions that are vital for life : liquid water, mild temperatures, a process to concentrate molecules, a complex natural environment, and trace metals.
Back in 1967, Harold Morowitz and Carl Sagan had speculated that the clouds of Venus may harbor life. On earth, phosphine is only made industrially or by microbes that flourish in oxygen-free environments. This has led many scientists to believe that the possibility of life having existed on Venus can not be ruled out. However, many skeptics have stated that such extraordinary claims require extraordinary evidence. There are several possibilities for the existence of phosphine in the atmosphere of Venus, including lightning, volcanoes, and even delivery by meteorites. However, each of these would not be able to produce the level of phosphine detected.
The Russians claim Venus for their own
Jim Bridenstine of NASA called the discovery “the most significant development yet in building the case for life off Earth”. Under its Discovery Program, NASA is considering four space missions for launch later this decade, and two of them would be orbiters of Venus. However, it is not just NASA that has an interest in the planet. In the coming decades, the European Space Agency (ESA) is considering a planet-scanning radar probe of Venus.
Roscosmos, the Russian space agency, now says it is avoiding “wide international cooperation.” In a bizarre turn of events, Moscow has claimed Venus as a ‘Russian planet’. Russia seeks to preserve its preeminence on the planet. The Russian government believes the country has historically dominated the exploration of Venus.
We won’t meet our alien neighbors just yet
What is certain is that life on Venus at the moment is highly unlikely. Average surface temperatures on Venus reach up to 400℃ – I struggle to bear a Hamman for more than 5 minutes. Surface temperatures this hot make it impossible for liquid water to form, and these levels of heat would most likely destroy most organic molecules. Fear not ! We will not have the opportunity to meet our extraterrestrial overlords anytime soon.