It's because we want to know what is there already first.
If we introduce life to Mars - then after that - when scientists announce that they have found life on Mars - the obvious first assumption will always be "Sure, of course you have found life, what do you expect, after all we just introduced life to the planet, didn't we?".
That would turn what could be the most important discovery in biology of this century into a huge embarrassing and silly anticlimax.
So - we are very careful not to introduce life to Mars right now, or anywhere else, until we get a chance to look properly to see if there is life there already. But it is really hard to find - you can't see a microbe from orbit. And it may be in small colonies, just hanging on in thin films of liquid in a harsh landscape. Nevertheless it could well be revolutionizing - especially if it is based on a different biological basis from Earth life. It would be utterly tragic to lose the opportunity to find this life, just because we were careless about protecting the rest of our solar system from earth life.
It's not just of value to science and scientific understanding. Microbiology is our best nanotechnology. We can't match what life can do in many cases. So imagine if we had a whole new lifeform that was based on totally different principles?
Also finding another form of life could help us understand how our type of life works better too, by comparing the two. So could have implications for medicine, biology, agriculture, who knows what else. It's potentially of huge benefit to our civilization. Not saying that is bound to happen, we don't know if it is likely even. But just to have a chance of that, is something we can't let pass by just because we have neglected protecting the solar system from Earth life.
But apart from that, we have no idea how they would develop. It's like a huge experiment treating a planet like a petri dish.
It's okay to try introducing life to a petri dish in a laboratory and see what it does. Even let it evolve for some generations and see how it changes.
But if you do that to a planet - what do you do if the life evolves in a way you don't want? What for instance if it becomes hazardous to humans? Or it starts to transform the planet?
You can't just scrub the planet clean and start again. Your act of introducing life to it has divided the planets history into two halves, the billions of years before that when it didn't have life, and the billions of years afterwards when whatever follows on from your experiment develops there. Are we ready to take responsibility for the birth of a new ecosystem and its following billions of years of development? Or should we perhaps wait until we have learnt a bit more about planetary midwifery? And perhaps got to the point where we are long enough lived as a civilization to be able to keep an eye on the planet through its difficult early stages, and know what to do if it goes off the lines in its baby and toddler phases.
And - many seem to assume that introducing life to a planet will automatically make it more habitable for life. But in the past, Earth has gone into a snowball / slushball phase for millions of years when it was not nearly as habitable as it is now or was before. Mars may well have had life in the past, it may even have life now - we don't know but there are possible habitats not yet confirmed where Earth life could survive on the surface, so presumably Mars life also if it existed. So it could have life, but if so, it has not made it into a more habitable planet.
So there may well be quite an element of luck involved. Being on the right planet, with the right resources, and then, maybe the right things happening at the right time. For instance Earth's oxygenation event made the climate suddenly much colder because CO2, which is a greenhouse gas, got removed from the atmosphere. But the sun at the same time got warmer. That worked fine for Earth - but the same process would have been a disaster on Mars, plunging it into a freezing cold phase.
Lots of other things could go wrong.
See also my:
Imagined Colours Of Future Mars - What Happens If We Treat A Planet As A Giant Petri Dish?
Our Spacecraft Could Look Straight At an Extraterrestrial Microbe - And Not See a Thing!
Will We Meet ET Microbes On Mars? Why We Should Care Deeply About Them - Like Tigers
If we introduce life to Mars - then after that - when scientists announce that they have found life on Mars - the obvious first assumption will always be "Sure, of course you have found life, what do you expect, after all we just introduced life to the planet, didn't we?".
That would turn what could be the most important discovery in biology of this century into a huge embarrassing and silly anticlimax.
So - we are very careful not to introduce life to Mars right now, or anywhere else, until we get a chance to look properly to see if there is life there already. But it is really hard to find - you can't see a microbe from orbit. And it may be in small colonies, just hanging on in thin films of liquid in a harsh landscape. Nevertheless it could well be revolutionizing - especially if it is based on a different biological basis from Earth life. It would be utterly tragic to lose the opportunity to find this life, just because we were careless about protecting the rest of our solar system from earth life.
It's not just of value to science and scientific understanding. Microbiology is our best nanotechnology. We can't match what life can do in many cases. So imagine if we had a whole new lifeform that was based on totally different principles?
Also finding another form of life could help us understand how our type of life works better too, by comparing the two. So could have implications for medicine, biology, agriculture, who knows what else. It's potentially of huge benefit to our civilization. Not saying that is bound to happen, we don't know if it is likely even. But just to have a chance of that, is something we can't let pass by just because we have neglected protecting the solar system from Earth life.
But apart from that, we have no idea how they would develop. It's like a huge experiment treating a planet like a petri dish.
It's okay to try introducing life to a petri dish in a laboratory and see what it does. Even let it evolve for some generations and see how it changes.
But if you do that to a planet - what do you do if the life evolves in a way you don't want? What for instance if it becomes hazardous to humans? Or it starts to transform the planet?
You can't just scrub the planet clean and start again. Your act of introducing life to it has divided the planets history into two halves, the billions of years before that when it didn't have life, and the billions of years afterwards when whatever follows on from your experiment develops there. Are we ready to take responsibility for the birth of a new ecosystem and its following billions of years of development? Or should we perhaps wait until we have learnt a bit more about planetary midwifery? And perhaps got to the point where we are long enough lived as a civilization to be able to keep an eye on the planet through its difficult early stages, and know what to do if it goes off the lines in its baby and toddler phases.
And - many seem to assume that introducing life to a planet will automatically make it more habitable for life. But in the past, Earth has gone into a snowball / slushball phase for millions of years when it was not nearly as habitable as it is now or was before. Mars may well have had life in the past, it may even have life now - we don't know but there are possible habitats not yet confirmed where Earth life could survive on the surface, so presumably Mars life also if it existed. So it could have life, but if so, it has not made it into a more habitable planet.
So there may well be quite an element of luck involved. Being on the right planet, with the right resources, and then, maybe the right things happening at the right time. For instance Earth's oxygenation event made the climate suddenly much colder because CO2, which is a greenhouse gas, got removed from the atmosphere. But the sun at the same time got warmer. That worked fine for Earth - but the same process would have been a disaster on Mars, plunging it into a freezing cold phase.
Lots of other things could go wrong.
See also my:
Imagined Colours Of Future Mars - What Happens If We Treat A Planet As A Giant Petri Dish?
Our Spacecraft Could Look Straight At an Extraterrestrial Microbe - And Not See a Thing!
Will We Meet ET Microbes On Mars? Why We Should Care Deeply About Them - Like Tigers
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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