wut?

Green Bank Observatory, Green Bank, WV.

https://greenbankobservatory.org/

I've visited there 3 times, beautiful area, and a small scientific community unto itself.

If you have a chance, visit.

quote:

Originally posted by SIGnified:
wut?

Haha, I said the same thing after reading that.

Not a huge problem. A lot of low power communications never actually exit the atmosphere. They are reflected back towards the ground.

Microwave communications are hampered because the energy is easily absorbed by water vapor in the atmosphere. Just think about how your microwave oven works.

A really focused beam can get away but yes, the inverse square law kicks in really quickly.

Looking up at the night sky is looking back in time. Except for the solar system objects, what you see at night is what it looked like when the light left the object. Just for giggles look up the distances to the major stars in Orion of the Dipper.

quote:

Originally posted by preten2b:
Soooo.. If we knew messages couldn't be received at any meaningful distance, why did we spend good money trying to listen to worlds far beyond??

Because they were tax dollars.

The Great Barrier Theory pretty much guarantees we are a fluke.

Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.

quote:

Originally posted by Mars_Attacks:
The Great Barrier Theory pretty much guarantees we are a fluke.

Not only this, but the incredibly vast distances all but guarantee we will never have contact with another civilization.

As pointed out, while our bubble of light speed communication might be 100 light years in an expanding sphere, a vast majority of this influence is too weak to even get very far. Now add in that another civilization must be able to detect it, or even recognize what they’re detecting.

Then consider the possibility that “they” may exist in a state of constant lack of cooperation as we see on this planet. Despite our technological advances, we seem to be sliding in the wrong direction in a number of categories.

Now add in the vast distances involved- if we detected a radio signal from, say, 100 light years away, that signal is now 100 years old. Let’s say it’s further; 1000 light years. Or 10,000. Or a million. Is this civilization still around? If we set out at light speed towards the origin, it would take us as long to get there as the signal took to get to us.

There is a lot of aspects to consider about space travel and what is in it for us. Do we start loading up Arks with people and supplies and fling them into the void on one way trips? Unless our goal is exploring only our solar system, that’s what any meaningful attempt would amount to. One way trips of exploration that would basically mean cutting ties with the earth forever.

Here's the problem with this whole discussion... we are limiting this to light years....

most of the universe it seems is made up of some 'other' substance that it seems our greatest minds can't quite figure out... and that substance is not confined to the speed of light but 'constant'.

In other words it is all connected and instantaneous across the entire universe! It's best not to think too much about this or your head will explode and it might adversely effect some'one' 2 gazzilon light years away.

And just as we wrap our heads around the distances involved and speed of light limits, and dark matter, lets not forget the theory of folding space so that 2 distant points can be right next to each other.

quote:

Originally posted by Balzé Halzé:

quote:

Originally posted by SIGnified:
wut?

Haha, I said the same thing after reading that.

The constant erosion and dismissal of STEM education is apparent.

No wonder people are so easily duped by media and legislators, who themselves are the most ignorant of all.

We owe everything to physics and mathematics(and Newton). If scientists are such charlatins, how are you using a computer?

Relative size of "space" (as quickly related in a physics class).

IF the sun were the size of a quarter and located in Fort Worth, the nearest star would be located near Boston and, Earth would be smaller than a grain of sand located less than 10 meters away from said quarter.

So now ask yourself, "self, just how much do we really know about any other star when we are talking about those distances when observed from said grain of sand using equipment much smaller than an electron and, how much is just a guess?"

not looking outwards means that we think
that we're the only intelligent life - so why bother

it also assumes that if there were other life out there, they can't be as advanced as us so why bother

given the age of the universe, we've only really been a technologically 'advanced' civilization for a few hundred years

if we're they only life here, space is a pretty big waste

quote:

Originally posted by flashguy:

quote:

Originally posted by Hildur:
So signals via microwaves and light don't degrade over distance? I can shine my flashlight at the stars and some alien 100 light years away 100 years from now is going to wonder where that came from?

Radio waves, microwaves, light, and even gamma rays are all forms of electromagnetic waves, and subject to degradation by the inverse square law. Cosmic rays and high-energy particle jets can travel much greater distances with little degradation.

The stars and galaxies we see that are hundreds, and even billions of light-years away are visible only because they were very intense to begin with.

flashguy

I'm nitpicking terminology, but this might help to visualize what is going on. Waves/Particles are difficult to visualize if you try to think about both - it seems contradictory.
Electromagnetic radiation doesn't 'degrade', but it will spread out and appear weaker at a given point (wave). A photon (particle) from a flashlight (or radio transmitter) will travel in a straight line at the speed of light forever with the same 'intensity' in a vacuum. If it hits something (which is not possible in a perfect vacuum), it can lose energy & be deflected, or other situations we will ignore in the rest of this post.

So it is true to say that photons emitted by mankind's radio transmitters have a maximum possible distance travelled from earth of ~100 light years. Mankind wasn't transmitting anything before & the photons that didn't hit anything have travelled at the speed of light (c) for ~100 years. If we assume 1895 as the 1st radio transmission, it's closer to 130 light years, but really 100 vs 130 light years isn't significant in the context of the picture of the Milky Way vs a ~200 light-year sphere around Earth.

What 'degrades' is the SIGNAL. Example, turning a flashlight on & off in Morse code during daytime. All the photons (the 'light beam') look like they are travelling together in straight lines, if you could see it in daylight. But, they actually have slightly different angles & will spread apart as they travel further and it will be much harder to 'detect' the specific photons from the flashlight. Also, photons from the sun & other light sources with about the same energy (light color) are going to hit your eye at the same time.
On a bright day, with a weak flashlight, this can happen over naked-eye distances - you might be able to see the person holding the flashlight, but not whether it is on or off. The photons from the flashlight are reaching your eye in the same pattern, but they are impossible to recognize as such. "Looking for a needle in a needlestack" comes to mind.

Now imagine that over ridiculously huge distances. The transmitted signals are so spread out & so mixed in with other, very similar, EM radiation that it is almost impossible to separate & 'tune in' the original signal.
Aricebo radio telescope was 1000ft in diameter. The Square Kilometer Array plans to have 1 million+ antenna on at least 2 continents. It will look at REALLY powerful flashlights (pulsars) transmitting through near-vacuum and still need huge receivers to detect them with any accuracy.

It is my opinion that, if the Bible's version of creation is remotely correct, man is not made in God's image. Women are. The only way to explain why physical laws are so contradictory to common sense is to have them created by a woman.

quote:

Originally posted by nhtagmember:
Not a huge problem. A lot of low power communications never actually exit the atmosphere. They are reflected back towards the ground.

Microwave communications are hampered because the energy is easily absorbed by water vapor in the atmosphere. Just think about how your microwave oven works.

That's just not true. Dish-TV uses freqs just above 12 GHz, and yes, there is often some rain/snow attenuation, depending, but lower microwave freqs are less affected.

Signals just above 2 GHz and just above 8 GHz make it to and from Voyager all the time. Microwave ovens are at 2.45GHz, just above one of the Voyager channels.

Tons more examples of microwave freqs making it to the geo-sync orbit which is about 22,000 miles away

quote:

Originally posted by snidera:


Now imagine that over ridiculously huge distances. The transmitted signals are so spread out & so mixed in with other, very similar, EM radiation that it is almost impossible to separate & 'tune in' the original signal.

After a while inverse square law (previously mentioned) will cause the signal to be so weak that the thermal noise floor dominates.

So, how do we communicate with V'Ger?

Someone was listening, and they responded.

How do we know that alien technology isn't capable of picking up our radio waves at distance?

Here's an interesting video, 'Why Going faster than light leads to time paradoxes' (about 25 mins long). While it might not explain about our radio transmissions into space, it might explain why nobody has come to visit.

https://www.youtube.com/watch?v=an0M-wcHw5A