# How far away could we detect ourselves?

• nottheone
In summary, the question is how far away an alien species with a SETI program could be and still detect an Earth signal that would register as intelligent life. The answer is that at radio frequencies, our chatter outshines the Sun and could be detected at the other end of the galaxy with our current technology. The most powerful signal we have sent, the Arecibo message, could be detected by a SETI program from the other end of the galaxy. However, if the signal is a one-time event, the chances of it being picked up by our SETI program are slim. The conversation also touches on the idea that all of our signals may be lost in the noise within a few hundred light years.
nottheone
If we were an alien species withe a SETI program, with exactly the same technological capabilities, how far away could we be and still detect an Earth signal that would register as intelligent life? (ignore the travel time, assume all signals have had enough time to get as far as they can, obviously if the first signal we emitted was a year ago the answer would be one light year) If the answer is longer than when we emitted the signal, when would that signal be detected by this race?

This is off the cuff form memory of something I heard in a talk time ago, the point was that at radio frequencies our chatter outshines the Sun, and it could be detected at the other end of the galaxy with roughly our present level technology.

I am asking because I thought I heard somewhere that all our signals were lost in the noise not too many light years away, less than a few hundred.

The most powerfull signal we've ever sent was a special http://archive.seti.org/seti/seti-background/arecibo.php" , and would be detectable by a SETI program like our own from the other end fo the gallaxy.

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Depends on the bread. :) And it's petroleum. And I don't think a one time event counts. The chances of our SETI program picking up a one time event are slim to none. I am talking about repeated events, normal traffic.

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## 1. How do we detect ourselves from a far distance?

We detect ourselves from a far distance through various technologies such as radio and optical telescopes. These telescopes use advanced instruments and techniques to capture and analyze signals from our planet.

## 2. What is the farthest distance at which we can detect ourselves?

The farthest distance at which we can detect ourselves depends on the sensitivity of the instruments and the strength of the signals we emit. Currently, we can detect our own radio signals up to about 100 light years away.

## 3. Can we detect ourselves from other planets?

Yes, we can detect ourselves from other planets using similar methods as mentioned before. However, the distance at which we can detect ourselves from other planets may vary depending on the distance between the planets and the sensitivity of the instruments used.

## 4. How long does it take for our signals to reach a faraway point and be detected?

The time it takes for our signals to reach a faraway point and be detected depends on the distance and the speed of the signals. For example, it takes about 8 minutes for our radio signals to reach Mars and be detected by a spacecraft there.

## 5. Are there any limitations to detecting ourselves from far distances?

Yes, there are limitations to detecting ourselves from far distances. The signals we emit weaken and degrade over long distances, making it more difficult to detect them. Additionally, interference from other sources can also affect the accuracy of our detection.

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