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How bright is the Earth?

Hambil

Hambil

I AM A GOLDEN GOD
I did some googling, but didn't find an easy answer, so I'm bringing here to my TK friends.

The Earth puts out radio waves, and other energy, from the billions of people living on it and using cellphones, listening to radio stations, tv broadcasts, etc...


What does this amount to in 'luminosity' on the steller scale? Can we even be seen from a distance next to our sun?

Also, how cohesive are this waves? I assume as they pass by or through steller bodies they would distort and breakup.
 
How should I state this.... the only way we could be found among 100 billion stars would be through diligent, active listening.

It's not that the signal is faint (I don't know of any specific power,) it's that there is so much clutter in the galaxy aside from it.
 
If that's true (and I'll work of that assumption until someone finds numbers), then also consider the extremely short time frame in which the earth has been, and will be, putting out such signals.

Around a hundred years so far, which in cosmic terms is a nano-second. And technology is changing so that such signals will not be bleeding out into space much longer - simply because it's not efficient.

Now combine this with my belief (and Einstein's) that faster than light travel isn't possible, and then consider the size of the universe. What this all leads me to is that the universe could be teaming with life - intelligent and advanced life even, and we wouldn't know.

Earth is a needle in a very, very big haystack.
 
Based on the non faster than light travel why would anyone care to attempt to find life out there? It would not be possible to have any remotely reasonable means of communication. Much like a 2 things kept in a box apart from each other all their life. Sure there may be life... but effective communications? Naw. I would say that light speed would require being broken before we have visitors from other worlds or anything of that nature. closest system is Alpha Centauri. It has 3 stars and life is most likely not around to party. 4.3 light years away and is the closest thing we have that would provide meaningful conversation if other life was found. 4 year old conversations might provide good fruitful. Also considering the common thoughts that if we ran into other life there is a tendancy to think they would be more advanced than us. Face people... we might just be the most advanced civilization in the universe. We might also be the dumbest! Who knows?

As far as how bright el planet urth is... well take a trip to space and then get a measurement. all guess right now are just that! guesses!
 
Astral said:
Based on the non faster than light travel why would anyone care to attempt to find life out there? It would not be possible to have any remotely reasonable means of communication. Much like a 2 things kept in a box apart from each other all their life. Sure there may be life... but effective communications? Naw. I would say that light speed would require being broken before we have visitors from other worlds or anything of that nature. closest system is Alpha Centauri. It has 3 stars and life is most likely not around to party. 4.3 light years away and is the closest thing we have that would provide meaningful conversation if other life was found. 4 year old conversations might provide good fruitful. Also considering the common thoughts that if we ran into other life there is a tendancy to think they would be more advanced than us. Face people... we might just be the most advanced civilization in the universe. We might also be the dumbest! Who knows?

As far as how bright el planet urth is... well take a trip to space and then get a measurement. all guess right now are just that! guesses!
Click to expand...
Assuming we can travel at near the speed of light, then consider a few things.

Communication would not be delayed for the colony and the alien civilization it was established near. Nor would it be delayed for Earth and any race that established a colony close by.

Colonization is the likely method for exploring the universe without faster than light travel.

Also consider that the people traveling at near the speed of light don't age as we would, so the logistics of moving large numbers of people long distances (e.g. food, medicine, etc..) is not as bad as it might seem.

Most likely these Colonies will be independant, since any kind of military rule from that great a distance would be problematic.

I believe the direction exploring space is going to take is continuing refinement of 'planet' and 'life' hunters. Both via technology from earth (fancier telescopes, radioscopes, etc...) and via exploration satalites launched toward promissing planets and stars.

If we can find a life baring planet, then the effort to colonize near it or on it become worth while.
 
Hambil said:
I did some googling, but didn't find an easy answer, so I'm bringing here to my TK friends.

The Earth puts out radio waves, and other energy, from the billions of people living on it and using cellphones, listening to radio stations, tv broadcasts, etc...


What does this amount to in 'luminosity' on the steller scale? Can we even be seen from a distance next to our sun?

Also, how cohesive are this waves? I assume as they pass by or through steller bodies they would distort and breakup.
Click to expand...


The shorter the wavelength the more likely the radiation will be scattered by atmosphere and intersteller materials. That is why radio wavelengths can be used for long distance communication. As for the question would we be noticed from a distant world... that is possible, but depends on how far such intellient beings are from Earth, relative to who long humanity has been broadcasting, as well as the technologies being used to gathering the radiation. Due to the nature of radio frequencies to pass through gas and dust with little to no effect, SETI uses radio dish arrays to search for patterns that can not be ruled out by known sources in hopes to find a stray signal or perhaps even a signal directed towards Earth.

Ironically enough though, even the first intentional raido broadcast from Earth would have traveled only about 100 light years by now, and Im sure was a relatively weak signal to begin with. If some distant civilization happens to detect this broadcast, and decieded to send a response, we would have to wait the same amount of time it took the original signal to reach these intelligent beings. Not to mention technologies are continuely changing, and whos to say that some distant intelligent life would use radio for long distants communication. Which may be likened to some stone-age technology in comparison to their own. As for how luminous the Earth is... the the Earth does emmit various forms of electromagnetic wavelengths, Earth does not radiate visiable light, therefore the luminosity scale used by astronomer to compare the luminosity of stars would not necessarily apply. For objects that do not emmit their own visiable light a scale to measure albedo (how much light is reflected by an object)... the Earth's is has an average albedo of about 30%. If you wanted to look up how much radiation Earth emmits within various wavelengths you might have more luck finding what your looking for.
 
It all comes back to the issue of the scarcity of intelligent life in the universe, although it's a tangent in this thread.
 
Hambil said:
I did some googling, but didn't find an easy answer, so I'm bringing here to my TK friends.

The Earth puts out radio waves, and other energy, from the billions of people living on it and using cellphones, listening to radio stations, tv broadcasts, etc...


What does this amount to in 'luminosity' on the steller scale? Can we even be seen from a distance next to our sun?

Also, how cohesive are this waves? I assume as they pass by or through steller bodies they would distort and breakup.
Click to expand...

The greater the distance a form of radiation travels the more spreadout the signal becomes, or you might say stretched in a sense. The shorter the wavelength the more likely the radiation will be scattered by atmosphere and intersteller materials. That is why radio wavelengths can be used for long distance communication and studying the likes of nebulas. As for the question would we be noticed from a distant world... that is possible, but depends on how far such intellient beings are from Earth, relative to who long humanity has been broadcasting, as well as the technologies being used to gathering the radiation. Due to the nature of radio frequencies to pass through gas and dust with little to no effect, SETI uses radio dish arrays to search for patterns that can not be ruled out by known sources in hopes to find a stray signal or perhaps even a signal directed towards Earth.

Ironically enough though, even the first intentional raido broadcast from Earth would have traveled only about 100 light years by now, and Im sure was a relatively weak signal to begin with. If some distant civilization happens to detect this broadcast, and decieded to send a response, we would have to wait the same amount of time it took the original signal to reach these intelligent beings. Not to mention technologies are continuely changing, and whos to say that some distant intelligent life would use radio for long distants communication. Which may be likened to some stone-age technology in comparison to their own. As for how luminous the Earth is... the the Earth does emmit various forms of electromagnetic wavelengths, Earth does not radiate visiable light, therefore the luminosity scale used by astronomer to compare the luminosity of stars would not necessarily apply. For objects that do not emmit their own visiable light a scale to measure albedo (how much light is reflected by an object)... the Earth's is has an average albedo of about 30%. If you wanted to look up how much radiation Earth emmits within various wavelengths you might have more luck finding what your looking for.
 
Hambil said:
I did some googling, but didn't find an easy answer, so I'm bringing here to my TK friends.

The Earth puts out radio waves, and other energy, from the billions of people living on it and using cellphones, listening to radio stations, tv broadcasts, etc...


What does this amount to in 'luminosity' on the steller scale? Can we even be seen from a distance next to our sun?

Also, how cohesive are this waves? I assume as they pass by or through steller bodies they would distort and breakup.
Click to expand...

The more distance a wavelength of radiation travels the more spreadout and stretched the signal becomes. The shorter the wavelength the more likely the radiation will be scattered by atmosphere and intersteller materials. That is why radio wavelengths can be used for long distance communication. As for the question would we be noticed from a distant world... that is possible, but depends on how far such intellient beings are from Earth, relative to who long humanity has been broadcasting, as well as the technologies being used to gathering the radiation. Due to the nature of radio frequencies to pass through gas and dust with little to no effect, SETI uses radio dish arrays to search for patterns that can not be ruled out by known sources in hopes to find a stray signal or perhaps even a signal directed towards Earth.

Ironically enough though, even the first intentional raido broadcast from Earth would have traveled only about 100 light years by now, and Im sure was a relatively weak signal to begin with. If some distant civilization happens to detect this broadcast, and decieded to send a response, we would have to wait the same amount of time it took the original signal to reach these intelligent beings. Not to mention technologies are continuely changing, and whos to say that some distant intelligent life would use radio for long distants communication. Which may be likened to some stone-age technology in comparison to their own. As for how luminous the Earth is... the the Earth does emmit various forms of electromagnetic wavelengths, Earth does not radiate visiable light, therefore the luminosity scale used by astronomer to compare the luminosity of stars would not necessarily apply. For objects that do not emmit their own visiable light a scale to measure albedo is used (how much light is reflected by an object)... the Earth's is has an average albedo of about 30%. If you wanted to look up how much radiation Earth emmits within various wavelengths you might have more luck finding what your looking for.
 
The earth spawned humans.

I don't think the Earth was very bright in that instance.
Kind of like then you get drunk, wake up not knowing what you did, but have an STD.
And people tell you funny stories about what went on.
But you don't remember it, so you can neither comferm nor deny the stories. Just the result.
 
HEX said:
The shorter the wavelength the more likely the radiation will be scattered by atmosphere and intersteller materials. That is why radio wavelengths can be used for long distance communication. As for the question would we be noticed from a distant world... that is possible, but depends on how far such intellient beings are from Earth, relative to who long humanity has been broadcasting, as well as the technologies being used to gathering the radiation. Due to the nature of radio frequencies to pass through gas and dust with little to no effect, SETI uses radio dish arrays to search for patterns that can not be ruled out by known sources in hopes to find a stray signal or perhaps even a signal directed towards Earth.

Ironically enough though, even the first intentional raido broadcast from Earth would have traveled only about 100 light years by now, and Im sure was a relatively weak signal to begin with. If some distant civilization happens to detect this broadcast, and decieded to send a response, we would have to wait the same amount of time it took the original signal to reach these intelligent beings. Not to mention technologies are continuely changing, and whos to say that some distant intelligent life would use radio for long distants communication. Which may be likened to some stone-age technology in comparison to their own. As for how luminous the Earth is... the the Earth does emmit various forms of electromagnetic wavelengths, Earth does not radiate visiable light, therefore the luminosity scale used by astronomer to compare the luminosity of stars would not necessarily apply. For objects that do not emmit their own visiable light a scale to measure albedo (how much light is reflected by an object)... the Earth's is has an average albedo of about 30%. If you wanted to look up how much radiation Earth emmits within various wavelengths you might have more luck finding what your looking for.
Click to expand...


I will extricate myself from this conversation. The concept of people aging differently because of their velocity is sheer stupidity. I refuse to continue this discussion with idiots! I get enough with dealing with messenger in the other thread!
 
Astral said:
I will extricate myself from this conversation. The concept of people aging differently because of their velocity is sheer stupidity. I refuse to continue this discussion with idiots! I get enough with dealing with messenger in the other thread!
Click to expand...
Yes, please do extricate yourself. Since you don't believe in the theory of special relativity, despite the fact that it has been proven numerous times, I'd prefer not to hear from you.

In the mean time, try reading, it's good for you. Here are some suggested texts:

Einstein for Dummies
The Complete Idiot's Guide to Understanding Einstein, Second Edition (Paperback since I'm guessing you don't make much money)
 
Allow me to attempt to help.


I don't know the exact numbers involved in Earths luminosity but I think that's not really important for what you want to know. I assume you're interested in our ability to be detected by possible intelligence at reasonable distances, which would have to run into the 100's of light years at a minimum to even have a hope in hell of actually reaching some form of intelligence.

Well, it depends what you mean by detection. Detection of the human race on Earth or detection of the ability of Earth to support intelligent life.

The latter is quite promising. With telescopes of the same capability or slightly better than what we have - and who wants to find a race dumber than us anyway - we are very detectable. Probably from 1000's of light years away. And they would also be able to spectroscopically detect light reflected from the atmosphere of Earth and detect methane and oxygen which would make us stick out as a promising target for intelligence and confirm Earth as a living world. But they still wouldn't be sure if anything like intelligence had yet developed.

So Earth is not that hard for an alien species to detect under those criteria even from a rather distant species.


As for radiowaves that's a whole different kettle of fish. I think you're all being pretty generous by saying we've been kicking out radiowaves for 100 years. Sure we've had that technology for that long but upto about the latter half of WW2 we were mostly using low freqency AM radio that tends to be refracted by the Earths ionosphere and thus rarely makes it into space, above and beyond. Since then of course we've had much more high frquency powered radiowaves and such, and those do escape into space with ease.


But even with megawatt transmissions they're still going to be pretty weak by the time they reach say, 100 light years away, and of course these aliens would need huge SETI type recievers to detect the signals. Military radar and the like are much better candidates for being detected due to the higher power they use but still we're going to have to be VERY generous to say that we are detectable through these means upto 100 light years away. I'm not sure of the exact distance but it's around that.


So conceivably thousands of stars within our immediate vicinity, upto say, 50-100 light years can watch our TV without paying their TV licences and of course the distance keeps on reaching further day in, day out, but I'm not going to get my hopes up for intlligent life within 100 light years. I just doubt it. 1000 or so, yes. So we probably have allready been detected. I'd say that wasn't that much of a science fiction stretch whatsoever. They just can't be sure if there is intelligence here, but I'm sure Earth is listed as a possible subject for intelligent life by some civilization somewhere.
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Water reflects a lot of light kind of like a mirror. The earth is 2/3rds-3/4ths water, so that makes it pretty bright. However, the brightness of the earth from space has diminished a bit due to pollution. So while the earth is still pretty bright, most humans infesting it aren't. ;)
 
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