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A comment on SETI@home shuts down after 21 years. Parent comment

Re:SETI@home shuts down after 21 years by ars on Tuesday March 03, 2020 @09:26PM (#22480696)
Radar. That's the RF that's easiest to detect from long distances, it's focused, and it's strong.

The hard part is deciding if it's natural or artificial.

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Re:SETI@home shuts down after 21 years by Beldin on Tuesday March 03, 2020 @09:48PM (#22480791)
Top of my head, so I may be off, but: The Arecibo message was easily the easiest to detect by far. Its signal will become indistinguishable from background radiation at a distance of slightly over 625 light years.

The converse: any life out there trying their best to communicate with us, beyond 600 ly... we wouldn't realize it even if we happened to catch (what's left of) the signal.

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Re:SETI@home shuts down after 21 years by tgflynn on Wednesday March 04, 2020 @09:09AM (#22483850)
> Its signal will become indistinguishable from background radiation at a distance of slightly over 625 light years.

Doesn't that depend on how large the receiving antenna is, because the larger the antenna the smaller the source angle you can focus on and the less background radiation will be in that source angle ?

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Re:SETI@home shuts down after 21 years by StillBored on Tuesday March 03, 2020 @09:51PM (#22480798)
That may not last much longer either. Transponders are more effective/useful for civilian purposes and the military needs to be stealthy. Big radar installations have a sign painted on them that says "take me out first".
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Re:SETI@home shuts down after 21 years by hcs on Wednesday March 04, 2020 @01:09AM (#22481570)
What about radar for asteroid detection? https://en.wikipedia.org/wiki/Radar_astronomy
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