Visitors

Originally posted by woodypusher
...until Lisa Nowak came along 😲

What a memory you have!

I remembered the incident, particularly the diapers aspect of it, but I had forgotten the name of the astronaut.

Originally posted by johnnylongwoody
They say we are listening and watching outer space for intelligent life.

They also say we are sending signals into outer space to see if that will
attract intelligent life from other galaxies and planets.


Is this wise? Do we really want to attract the wrong sort?

If there is such a thing as the wrong sort out there
would we be wiser if we shut up?


Discuss....................................

Remember how in war of the worlds micro-organisms killed the aliens?

That might be very real concern to life forms from a different solar system. I doubt colonizing our world is practical even if an alien life form wanted to. They would avoid contact with our micro-organisms like....well...the plague.

A life form advanced enough to travel here would probably be responsible enough to avoid introducing their micro-organisms to our planet. A responsible visitor would not dare allow a fellow alien to come down here even in a sterilized space suit. One mishap would contaminate our would with DNA from their world. Forget ET walking around our planet. I can't imagine them doing something as stupid as that.

At most they would send robots to explore and gather specimens for study. If I were a curious alien looking to learn more about this world I would create a cyber insect and film everything in a very stealth way. Maybe they are doing that right now, but the vast distances from solar system to solar system are enough of a barrier to make that a bit unlikely.

Originally posted by Metal Brain
Remember how in war of the worlds micro-organisms killed the aliens?

That might be very real concern to life forms from a different solar system. I doubt colonizing our world is practical even if an alien life form wanted to. They would avoid contact with our micro-organisms like....well...the plague.

A life form advanced enough to travel here woul ...[text shortened]... istances from solar system to solar system are enough of a barrier to make that a bit unlikely.

Alien microbes would have the same chance or less of infecting humans than
the ones already on our planet.

The immune system uses a 'lock and key' approach to recognising pathogens.
Through combinatorial mechanisms, each cell is able to recognise vast
amounts of difference keys (non self's) and dispose of them accordingly.
Even if the 'keys' were of alien origin, the human immune system would still
be able to recognise them.

Viruses utilise cellular apparatus in order to reproduce. This is usually so
specific as to restrict a pathogen to a particular species.
A virus built to invade and replicate in an alien host would not be able to
do so in humans without an exceptionally high degree of similarity.

Originally posted by woodypusher
Doesn't that presuppose they'll be human and/or they'll want (or are capable of) to have sex with us? Even if they were, that hasn't been much of a repellent here on Earth.

Our idea of sex might be totally different from a theoretical galactic norm. Maybe their sex would involve intermixing plates of flesh, who knows what kinds of sex are possible.

The more fundamental issue would be if they even have our kind of DNA with its double helix.

Just recently a quadraplex helix was discovered in humans! So the double helix is not the only story for the huge amount of information needed to grow humans.

There may be shapes we have not even imagined, maybe a triple helix shape or a slinky shaped DNA or maybe even disconnected smaller structures that self assemble later.

The point is, there would be little chance of their bugs and our bugs being able to infect each other's ecology, plants, animals, sea creatures, birds, insects, etc.

Here is a link to the discovery of the quadruple DNA structure in humans:

http://www.newscientist.com/article/mg21729014.400-quadruple-helix-dna-discovered-in-human-cells.html

For instance, our chromosomes have telomeres on the ends to protect them from damage but what if some life form out in the galaxy developed torus shapes removing the need for end protection in the first place, perhaps making near immortals.

Originally posted by Thequ1ck
Alien microbes would have the same chance or less of infecting humans than
the ones already on our planet.

The immune system uses a 'lock and key' approach to recognising pathogens.
Through combinatorial mechanisms, each cell is able to recognise vast
amounts of difference keys (non self's) and dispose of them accordingly.
Even if the 'keys' were of ...[text shortened]... t would not be able to
do so in humans without an exceptionally high degree of similarity.

I'm not talking about viruses per se'

The fact is we don't know what kind of microbes are on other planets and how they work. You are just guessing. We have flesh eating bacteria on this planet. There might be something that seems relatively harmless to us that would be a real danger to an other worldly life form. We just don't know.

I can't imagine an alien life form willing to risk introducing their microbes on this planet. I think it is even more unlikely that they would be willing to contaminate their own planet with ours. It just doesn't make sense from a pragmatic view unless they have no intention of returning to their own planet. Their eco system would be disrupted as would ours.

Originally posted by Metal Brain
I'm not talking about viruses per se'

The fact is we don't know what kind of microbes are on other planets and how they work. You are just guessing. We have flesh eating bacteria on this planet. There might be something that seems relatively harmless to us that would be a real danger to an other worldly life form. We just don't know.

I can't imagin ntion of returning to their own planet. Their eco system would be disrupted as would ours.

I'm guessing that microbes that evolved in alternative ecosystems are very
unlikely to adapt to ours, over thousands or even millions of years.

In the context of war of the worlds, it just doesn't make biological sense.

You might, however get a microbe that eats up all the oxygen or contaminates
soil, something like that.

And besides, compared to an alien culture capable of crossing space-time,
what's to say we're not the microbes?

I think if aliens did visit our planet they would've already done experiments on our atmospheric composition, viruses, temperatures, gravity, etc. and know if our planet was suitable for conquering or whatever else they have in mind. Maybe some of the UFO's were unmanned (unalienated?) drones sent here to measure all of that.

Deep Thought mentioned Twilight Zone earlier. My favorite episode was 'To Serve Man'. Aliens visited and made friends with us only to make us a food source. The alien was played by Ted Cassidy (Lurch on Addams Family). Another TZ episode had Roddy McDowell wind up in an alien zoo.

Originally posted by Thequ1ck
I'm guessing that microbes that evolved in alternative ecosystems are very
unlikely to adapt to ours, over thousands or even millions of years.

In the context of war of the worlds, it just doesn't make biological sense.

You might, however get a microbe that eats up all the oxygen or contaminates
soil, something like that.

And besides, compared to ...[text shortened]... alien culture capable of crossing space-time,
what's to say we're not the microbes?

There was a big fuss about spacecraft going to Mars carrying micro-organisms that could live on Mars. You underestimate our microbes and you surely underestimate any other worldy kinds. You should think of microbes as adaptable pests that will not relent. That is the reality.

"Personally, I don't think there's intelligent life on other planets. Why should other planets be any different from this one?"

Bob Monkhouse

Originally posted by woodypusher
...

Deep Thought mentioned Twilight Zone earlier. My favorite episode was 'To Serve Man'. Aliens visited and made friends with us only to make us a food source. The alien was played by Ted Cassidy (Lurch on Addams Family). Another TZ episode had Roddy McDowell wind up in an alien zoo.

The one with Rosy McDowell sounds a bit Kurt Vonnegut.

Some micro-organisms are very adaptable. They are called extremophiles.

http://www.infocusmagazine.org/5.3/eng_mars.html

Any alien that came to our planet's surface would be extremely irresponsible. I'm betting any space traveling life forms would be smart enough to never descend to Earth. Contamination would be too high of a risk.

Originally posted by Metal Brain
Some micro-organisms are very adaptable. They are called extremophiles.

http://www.infocusmagazine.org/5.3/eng_mars.html

Any alien that came to our planet's surface would be extremely irresponsible. I'm betting any space traveling life forms would be smart enough to never descend to Earth. Contamination would be too high of a risk.

There are several theories about the origins of life on Earth, one of them being the nebula cloud seeding theory of Linus Pauling, where a cloud or nebula in interstellar space seeds the whole solar system. If that is true then looking for life in our own solar system, Mars, Titan, whatever, they may all be some variation on our kind of DNA.

My guess is life formed from other nebula or whatever, will have completely different structures, for instance, it was just shown that humans are not just stuck with the double helix thing, but there has recently been found a quadruple helix. Since that has already been found in humans, it makes speculations about variations in what DNA can be like a lot more viable. Alien equivalent of our DNA could be vastly different and therefore an extreme high probability we could never infect them and vice versa.

Originally posted by sonhouse
Our idea of sex might be totally different from a theoretical galactic norm. Maybe their sex would involve intermixing plates of flesh, who knows what kinds of sex are possible.

The more fundamental issue would be if they even have our kind of DNA with its double helix.

Just recently a quadraplex helix was discovered in humans! So the double helix i shapes removing the need for end protection in the first place, perhaps making near immortals.

Quadruple Helix.... if you please, as is now known!! .... 😉

-m.

Edit: My apologies. I respnded to quickly to seeing double helix, and didn't read on. 😳