What is the panspermia theory and what does it say about the possibility that the universe is full of life

One of the big questions that we have not yet resolved, and that no one expects will be resolved in the short term, is the origin of life on Earth (or anywhere else).

Science has tried to understand it, but despite amazing progress, many inexplicable mysteries remain.

What could have triggered that that made life from non-life?

For there is a hypothesis, whose antecedents go back to the Old Kingdom in Egypt, and are also found in early Hinduism, in the philosophy of the Greek pre-Socratic philosopher Anaxagoras, and among Jewish and Christian Gnostics, which although it has been repeatedly discarded, has survived Over time.

It’s about the panspermia theory.

Some of those early sources argued that the entire cosmos is full of seeds and that life on Earth originated from them.

The modern version postulates – in a nutshell – that life exists throughout the Universe and can be transported through space from one place to another.

Certainly not proven.

And several experts point out that, even if proven, it would not necessarily solve the question of the origin of life.

Despite that, it is still interesting, and various discoveries have given it some credibility.

A team of prominent scientists from MIT and Harvard, for example, “are so sufficiently convinced of the plausibility of panspermia They have invested over a decade, and a good amount of funding from NASA and other funds, “notes the NASA Astrobiology blog,” to design and produce an instrument that can be sent to Mars and potentially detect DNA or the most primitive RNA “, and check if any form of life was brought to Mars.

Will it be possible?

As British physicist Brian Cox recounts, in a video from BBC Ideas and the British Open University, this is what we know:

Life is incredibly adaptable, just look at the way our own species has managed to thrive around the world.

And microorganisms, such as archaea and bacteria, have been able to modify themselves over millions of years of evolution to adapt to a wide range of conditions.

That means that today there are microbes that can survive on a variety of diets – sulfur, ammonia, the metal manganese – and in the presence or absence of oxygen.

Some even survive in the most extreme conditions on Earth.

Pyrococcus furiosus It thrives in hydrothermal vents on the seafloor. Its optimum growth temperature is 100 degrees Celsius, a heat that would kill most living things. While the antarctic Psychrobacter frigidicola prefers decidedly cooler things.

You can also find Extremophiles in hot acid or surviving desiccation in salt-covered deserts.

And some of those creatures can even cope with various extremes at once.

You can find Deinococcus radiodurans in both hot springs and Antarctic soil, it survives desiccation and is one of the most radiation-resistant organisms we know of.

All that makes Extremophiles are probably the organisms most capable of surviving and potentially colonizing the harsh environments of other planets and moons, provided liquid water is present at least part of the time.

But…

How would they get to those other places?

Well, the easiest way is to travel with us as we explore our Solar System and beyond.

Bacteria have been discovered in NASA spacecraft Tersicoccus phoenicis… ¿we will have accidentally introduced bacteria from Earth to the Moon and Mars?

Another possible way for these microbes to move through the Solar System is by hitchhiking on meteorites.

When these collide on a planet, rocks and debris fly out, generating more meteorites.

So far, they have found 313 Martian meteorites on Earth, and it was also found a terrestrial rock on the moon, from what we know that there has been interplanetary transfer of rocks.

But…

How would they manage to survive in space?

Once in space, those hardy travelers can easily cope with the cold and lack of oxygen.

Even normal bacteria, in extreme conditions, can enter a state of torpor by creating safe spaces surrounded by thick walls, which are known as spores, heat, cold, drought, acid and UV resistant bacterial DNA packages traveling through space.

However, a big problem is that space is teeming with ionizing radiation that destroys DNA.

But that’s not stopping Deinococcus. Groups of that little individual have survived three years of exposure to outer space. Others have survived up to six years as spores.

Another obstacle is time. Space is immense, so traveling anywhere takes a long time.

That said, in 2020, Japanese scientists revived bacteria that had been dormant on the ocean floor for 100 million yearsSo maybe the extraordinary distances are not a problem for those tiny space travelers.

The last step is to survive the crash landing in your new home.

And bacteria have been shown to do just that … as long as they are housed in deep fractures in cosmic rock.

It could be?

So microbial life may have already traveled somewhere like Mars.

Conditions there were remarkably similar to those on Earth 3.8 billion years ago.

Could these Extremophilic microbes have colonized the underground aquifers of Mars?

If they are already there, have they adapted to their new environment?

Or maybe life on Earth originated on Mars and then traveled to our planet?

They may not be little green aliens or intelligent life as we understand it, but the very possibility that life has transferred through the Solar System and beyond is deeply intriguing.

And with the James T. Webb Telescope beginning its search for telltale signs of distant life on other planets, could we perhaps discover that life is much more inevitable than we ever think?

* Much of this article is a video adaptation of BBC Ideas “Are we thinking about alien life all wrong?”, conducted with academic consultant Dr. Mark Fox-Powell, a researcher at The Open University, and presented by physicist Brian Cox.

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