If they do get detected by another civilization, likely to be hundreds of thousands of years from now, or millions, perhaps most likely billions of years from now.
For instance, Voyager 1 is due to pass within 1.7 light years of another star 40,000 years from now.
Interstellar Traveler: NASA's Voyager 1 Probe On 40,000-Year Trek to Distant Star
If there are ETs around that star, and they can detect something as small as Voyager from 1.7 light years away - that is extraordinary technology.
More likely need to wait until it passes within light hours of a star for even a high technology race to have a hope of detecting it and distinguishing it from comets and asteroids and other debris. For us, we would need it to pass within light seconds of Earth to do that, and it would need to approach Earth in the right direction also.
So - if they have the technology to detect it - they surely know about us already and probably know far more than there is on the ship. That is unless we are extinct by then - it could then be one of the few remaining relics in our galaxy of a long extinct ET (us) - or of an ancient ET (us again) that evolved into new species millions, or billions of years previously.
So - is more of a message to the far future like a time capsule than to the present. Though even in far future - unless ultra technological e.g. galaxy filled with technological ETs, might never be spotted.
For instance, Voyager 1 is due to pass within 1.7 light years of another star 40,000 years from now.
Interstellar Traveler: NASA's Voyager 1 Probe On 40,000-Year Trek to Distant Star
If there are ETs around that star, and they can detect something as small as Voyager from 1.7 light years away - that is extraordinary technology.
More likely need to wait until it passes within light hours of a star for even a high technology race to have a hope of detecting it and distinguishing it from comets and asteroids and other debris. For us, we would need it to pass within light seconds of Earth to do that, and it would need to approach Earth in the right direction also.
So - if they have the technology to detect it - they surely know about us already and probably know far more than there is on the ship. That is unless we are extinct by then - it could then be one of the few remaining relics in our galaxy of a long extinct ET (us) - or of an ancient ET (us again) that evolved into new species millions, or billions of years previously.
So - is more of a message to the far future like a time capsule than to the present. Though even in far future - unless ultra technological e.g. galaxy filled with technological ETs, might never be spotted.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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