Bacteria from the Earth’s surface is likely to have beaten humans to be the true winner of the space race, research suggests.
Scientists have discovered that tiny bacteria can travel much higher above the Earth than previously thought, suggesting they may have been travelling into outer space well before the first rocket voyage was conducted.
The bacteria could have landed on other worlds after being carried by high-speed vertical winds more than 120 kilometres above the planet’s surface – a distance far higher than previously thought and at an altitude that is considered to be in space.
During his orbit of the Earth, Gagarin, aged 27, travelled to a maximum altitude of 330km and was guided entirely by an automatic control system as he orbited Earth.
Before him, Laika the dog, as well as monkeys, chimpanzees and mice, had been sent into space. A 1947 rocket flight carrying fruit flies is thought to be the first time living creatures were sent into space.
The US operation saw the flies propelled into space on board captured German V-2 rockets to study radiation exposure at high altitudes.
The latest study, published in the journal Proceedings of the Royal Society A, notes that bacteria from Earth could have been taken far beyond the planet deep into space after being hit by “hypervelocity space dust”.
During a process referred to “life transfer” between the Earth and other worlds, some of these micro-organisms may have found their way to different planets.
The study, led by Prof Arjun Berera from the School of Physics and Astronomy at the University of Edinburgh, found that dust samples taken from outside the International Space Station had been found to contain DNA from several kinds of bacteria.
Prof Berera’s team found that powerful vertical winds can travel up to 150 metres per second and have the ability to blow “small bacteria-sized” particles up at least 120km into the air to reach “greater altitudes”.
Prof Berera told The National that researchers had set out to explore whether “atmospheric dynamics could allow for small biological sized particles to be propelled up to 150km.”
“Our paper showed that vertical winds do have the kind of force needed to allow such upward motion of small particles from lower in the atmosphere,” he said.
“The paper was still just a proof of concept and much more is still needed to understand the complex atmospheric dynamics of vertical winds. We looked at some specific cases based on known data, and that showed this sort of upward motion for small biological particles is possible.”
He said while the team could not find evidence suggesting particles could reach a height of 150km above the Earth’s surface, “we think it presents plausible evidence that this is possible, but more data and understanding of vertical winds is still needed.”
Meanwhile, the deadline to decommission the International Space Station, a collaboration between several nations which orbits the Earth at 400km, is fast approaching.
US President Joe Biden wants to extend the operation of the space station until 2030 but will need the approval of international partners including Russia to do so.
Approval from partners in Europe, Japan and Canada must also be secured if the ISS is to continue its work.