Friday 1 July 2016

Where Did All The Martians Go?

Mars is arguably the only place in the Solar-System, other than Earth, where intelligent life could have developed. There is a lot of evidence to indicate that Mars once had a much thicker atmosphere, with a significant surface ocean of water. If such ideal conditions for life existed for a billion or more years then it's possible that a technological civilisation developed.

Mars as it looked a billion years ago, before the decline of its atmosphere, climate and civilisation

But what happened, and where did all the Martians go?

A while ago I wrote about the evidence of a nuclear war on Mars, a war that devastated the entire planet's delicate ecosystem millions of years ago.  With its atmosphere and environment already in severe decline, and its oceans almost gone, the war was the fatal final step towards rendering the planet uninhabitable.

The ruins of a Martian city a few centuries after the final war

The survivors, providing they were technologically advanced enough, would have had only two choices: retreat underground, or evacuate to space.

I suspect that both choices were taken.

Mass Evacuation

Astronomers on Mars, much like on Earth, would have long been interested in finding similar planets to their own in other star-systems. And at least a few would have been found. With the knowledge that their own planet would soon be uninhabitable I expect plans would have been put into action to ensure the survival of their species. Over many centuries the Martians would have launched thousands of missions into space, and created colonies in the asteroid belt with the sole purpose of constructing a fleet of generation ships capable of sending tens of thousands to the planets they hoped they could settle on.

As each generation ship was completed thousands of Martians would have boarded and been launched on an interstellar journey, a journey that would have taken tens of thousand of years, and hundreds of generations, to complete.

One of the mysterious bright spots on the Ceres asteroid . Could this be evidence of previous or on-going Martian mining activity for interstellar spacecraft construction?

It is likely that dozens of such generation ships would have started on such journeys before that final war rendered the surface of Mars truly uninhabitable. Some of those ships would have reached their destinations. It is quite possible that there are now several flourishing colonies of Martians within a few tens of light-years of our Solar-System.

Deep Underground

Despite the exodus of tens of thousands into space, the majority of Martians would have had to remain on Mars. With the surface rapidly becoming uninhabitable there would have been no choice but to build vast underground cities with the ability to sustain populations of millions almost indefinitely. This would be an impossible task on a dying planet, but a subterranean facility suitable for a million or so could succeed. While millions would have perished as the final desperate war was fought, at least a significant population could be maintained far below the surface, ready to eventually leave Mars when the possibility arose.

Is that huge underground haven on Mars still occupied? Or has it been abandoned? There was evidence seen not long ago that could have been recent launches, perhaps shuttles on their way to the asteroid belt to join one of the last generation ships.

Could we have already witnessed the final evacuation of Mars?

The entrance way to a long abandoned underground Martian city

If we have then there will be at least one huge abandoned underground facility that could be used by human colonists. It's something that we should be actively looking for.

We need to be doing the following:

  • Searching for evidence of Martian colonies on planets around nearby stars.
  • Exploring the regions of Mars where the entrances to the underground cities may be located, perhaps near the larger subsurface water deposits, or near the poles. We need to be careful, as Martians may still be living there.
  • Excavate the ruins of Martian surface cities to learn about their culture, technology, and if possible obtain clues as to where their generation ships have gone.
  • Send probes to the asteroid belt to uncover evidence of the Martian interstellar shipbuilding activity.

Possible remains of a Martian surface city, taken by NASA's Mars Global Surveyor

There is so much to learn about this fascinating planet. It is quite possible that the secrets of a once flourishing technological civilisation are lying just beneath the surface. The tantalising evidence of ruined cities should be the target of manned archaeological expeditions as soon as a permanent human presence is established on the planet.

Once humans arrive on Mars I would expect to see a deluge of sensational discoveries.  We could find that we are not the first advanced civilisation to evolve in the Solar-System. Such a discovery will force all of us to reconsider our place in the universe. And it will provide humanity with a supreme motivation to embark on interstellar exploration at last.