21st century science predictions

[Mr Brightside]

Androids that you can do a sex with

[Ambient Sheep]

<tag>King Crimson first draft</tag>

[Paul Calf]

<tag>The Doors reunion 'lacks verve'</tag>

[MoonDust]

Life started on Earth as soon as it was cool enough to do so. I think that means complex chemistry almost always leads to the simplest life forms. So I believe life also got started on Mars, possibly Venus, and a few of the moons of Jupiter and Saturn. It's possible Mars (being smaller) cooled first and meteor bombardments moved that life to Earth. We could actually be Martians.

So simple single-celled life should be all across the universe. What about sentients like us? From the earliest life forms to us took a third of the entire lifetime of the universe so far. That's an incredibly long time during which a planet has to be stable and easily able to hold life. Also we have no idea how long civilisations survive or what they do when go beyond our technilogical level (assuming they do).

However it seems likely there are at least several dozens of active civilisations in our galaxy alone, right now. But space is big. I mean really big. Detecting them will be extremely difficult. There's a sphere of very weak radio transmissions expanding from the Earth. But it is only a little over 200 light years across. Tiny in comparison to the Milky Way.

TL;DR single celled blobs yes. Anything more complicated, almost certainly not.

That's pretty much what I think. Any advanced civilisation is unlikely to be existing within contacting distance, as you said, given the expanse of our galaxy alone, let alone our universe.

Unless of course teleportation is possible and not the re-mit of sci-fi, then the other civilisations could visit us pretty sharpish.

However if we are limited as to how fast we travel, and teleportation isn't possible, some scientists reckon that it's most likely any contact we have with another civilisation will be via that civilisation's machines rather than beings. As you could send a machine out into space and it'll last a lot longer than a lifeform. I reckon if we invent AI one of the first things we should do is blast it off somewhere towards a habitable exo-planet, and equip it with info for who we are and where we are. Can't see humans having "first contact" to be honest.

But yeah, simple organisms must be so common. As I said, would be a game changer if they had DNA too. If that's the case it's most likely to be found in martian organisms, if as you mentioned, life on earth coming from meteor bombardments on Mars is true.