The sky above Mars just got busy.
The Hope probe launched by the United Arab Emirates has just arrived in orbit around Mars, slowing from a cracking speed of 121,000 km/h. It joins China's Tianwen-1 spacecraft, already orbiting Mars and next week Nasa's Perseverance Rover lands to begin exploring the surface of Mars. Its primary goal is to search for life on the red planet.
And the quest to discover life beyond planet Earth is not just confined to Mars.
Just before Christmas, Peter Beck of Rocket Lab revealed plans to send a mission to Venus to search for life. Hard on the heels of this, astronomers from Cardiff and other institutions reported the presence of trace amounts of phosphine gas in the atmosphere of Venus – a possible signature of life, they suggest.
How realistic is this hugely expensive quest? Sceptics will say scientists will always have their grandiose pursuits and Nasa needs to position itself for continued funding. On the other hand, fortune does favour the brave. But does it favour the brash?
Scientists and engineers are usually understated, preferring to see a result firmly established before any bold claims are made. Science progresses with a healthy dose of scepticism.
So, when certainty is proclaimed in any field of research, the pushback is immediate and robust. Not, however, it would seem in the search for extra-terrestrial life.
Go back a decade. Researchers at the University of California reported the discovery of an Earth-sized planet orbiting a nearby star. Its distance from the star would make it not too hot and not too cold – possibly just right for life. One of the discoverers Professor Steven Vogt excitedly stated, "Personally, given the ubiquity and propensity of life to flourish wherever it can, my own personal feeling is that the chances of life on this planet are 100 per cent."
Overstatement like this should ring warning bells. Misplaced enthusiasm (hubris?) obscures the objective mind. His certainty was rather short-lived for he went on to state, "I have almost no doubt about it."
Yet we encounter similar statements quite regularly from Nasa and other scientists. One of the common messages is: if there's water out there, then life will surely be found – as though life were some simple inevitable consequence of a watery primordial soup, suitably warmed and stirred.
Indeed, Nasa's chief scientist recently warned: "The world is not prepared for the discovery of life on another planet even though it may only be a couple of years away."
It's an interesting thought, isn't it? Of course, Earth's microbes have been found circulating high in our atmosphere. Many can survive the most extreme environments. One would first have to demonstrate that any putative Martian or Venusian microbes didn't originate from Earth.
But, so inured are we to the idea of "life out there" that I would want to turn this on its head to say, "the world is not prepared for the discovery that there is no other life in our solar system, nor in our galaxy, nor anywhere else in the universe." We are unique.
I say this simply because life is unbelievably complex and improbable. As far as we can tell, we are preposterously lucky to be alive. A recent study from Oxford University concludes that we are probably alone in the universe. The ramifications, if this is true, are profound.
At the very least, it underscores our almost universal persuasion that life is sacred. Life requires vastly more than a mere felicitous combination of simple organic molecules and water. A recent article in the prestigious scientific journal, Nature, argues that life is so complex that we may never fully understand it – an infinite onion of layered complexity.
The central issue is that DNA coding is highly sophisticated and astonishingly efficient in terms of energy consumption and low error-rate. Then, the molecular machinery for copying, decoding and translating DNA to make proteins is more complex, requiring a large number of complicated proteins working in subtle consort to manufacture proteins. We have the inevitable chicken and egg puzzle: how did it all get started?
Some argue it all started with bacteria that survive in extreme conditions - so-called extremophiles - but these require additional molecular machinery to repair the rapid damage to DNA that accompanies extreme conditions. Is it really feasible that it all started with more complex life?
In my lab book, the search for extra-terrestrial life is a very, very long shot. I would prefer to tackle problems more likely to be resolved. Indeed, the art of the scientist is to identify what is achievable and the funding agencies usually crack that particular whip.
This doesn't seem to apply to the multibillion-dollar hunt for "life out there". It may be high-stakes Nobel Prize territory but, personally, I'm not holding my breath. I'd rather we looked after life down here.
• Dr Jeff Tallon is a physicist working mainly in the field of superconductivity.