Today is the 44th anniversary of the Arecibo message into deep space.

https://www.news.com.au/technology/...e/news-story/e7501d80bec109fe0988e8f1d8dfd3a5

Today is the 44th anniversary of the Arecibo message sent out into deep space.

Just think in a few thousand years there could be someone picking that message up. Isn't relativity fun?

 

Fun, yeah.. when they send something back.. like an invasion fleet..

 

We'll get a UFP fine for broadcasting to another celestial body without a license.

 

People worry too much. Invasion fleet. The chances of alien life getting any of our broadcasts is not very high. Wouldn't they have already come by now with all the junk our planet spews into space?

 

All that junk doesn't leave Earth orbit except the long range probes and even those have barely left the solar system...

 

In a few thousand years, I won't be anything more than dust. So bring it on.

 

Not space junk but EM junk, a world like ours with telecommunications, TV, radio and all other forms of comms would be like a bright spot in the night sky if anyone wanted to find us.

 

Most of our signals simply aren't powerful enough to broadcast very far...our early ground based radar systems might do the trick,
but the rest will be lost in the interstellar background noise

 

Still if you were looking at our solar system and our part of the galaxy Earth would stand out.

 

Unless there's some way around special relativity we don't know about I find an invasion fleet unlikely, just for economic reasons. There's no possible benefit they could get from invading us, the resources spent to bring anything back would cost more than the resources to get here, and they'd get those resources thousands of years late.

Unless of course they had no intention of going back to their home planet.

 

Well Earth is pretty good real estate if you want a nice planet to colonize just have to get rid of the bipeds that infest it.

 

https://www.theregister.co.uk/2015/07/16/america_soviets_space_race/
And very dimly possibly a radioactive manhole cover flying somewhere on its way to the Oort cloud right now

 

Bring it on, I have a baseball bat with their name on it.

 

If they invade just unleash a virus. There must be something in some secret lab somewhere for that occasion.

 

A virus would only work if the aliens have compatible RNA building blocks. Or the virus (assuming it can even enter the cell) simply does not know how to hijack the protein building machine to reproduce.

It’s probably easier to poison aliens than infecting them with the flu.

Even local species are immune to most virus.
A virus is a highly specialized self reproduction machine that needs exactly the right host or one close enough to overcome incompatibility by mutation.

 

Those are very good points I didn't think of.

 

Yeah like why? Why did they do that? Nude pics telling potential aliens "hey look!"

 

Travelling 25 Kly physically would be prohibitive. It will take millions of years with conventional propulsion, and while relativistic anti-matter propulsion may reduce travel time to around 90 Ka, dodging micrometeorites for that long would be like winning the lottery. Without some nerdy relativistic dust shield, they will be toast, and nerds are known to rather dwell underground in close proximity to their family abode, and not be much fond of rushing into battle. Even if the alien warriors are maniacal enough to devote thousands of years to storm our planet over a silly pixel depiction of their genitalia, and while we have time to mount their defence – our natural micrometeorite shield would have decimated them. If their craft is sturdy enough for a few of their cryo pods to survive the trip, we'll be answering their distress call when they arrive. That would be pretty embarrassing and humiliating – their only chance to avoid shame is if we've gone back to taking no prisoners.

I believe the aliens would rationally weigh their options, and conclude the smartest move is to sterilize the Earth with a giant gamma ray exactly 50 Ka from now, from which I would be perfectly safe in my underground shelter.

 

They won't find us as they'll be looking for a system with nine planets.