Which stars can see Earth as a transiting exoplanet?

Re:Which stars can see Earth as a transiting exoplanet? by mandevil on Wednesday October 27, 2021 @07:02PM (#29020107)

From the 1960's to the present, the Ballistic Missile Early Warning System radars have been broadcasting enormous amounts of coherent power on specific, non-natural frequencies into outer space: if we were to detect a signal like that we'd almost certainly determine it was artificial.

You can see the list of stars which would have recently started seeing the first glimpses of the BMEWS Line radars here: https://en.wikipedia.org/wiki/List_of_star_systems_within_55...

Obviously many other radars (DEW, Hen House, etc.) are doing the same thing, but BMEWS has continuous operation and power on its side.

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Re:Which stars can see Earth as a transiting exoplanet? by giantrobot on Thursday October 28, 2021 @01:37AM (#29022748)

In theory yes but in reality Earth rotates and orbits the Sun. Any particular observer outside our solar system has a very low probability of catching any one of those beams at the moment it's photons are reaching them.

There's also little chance of those beams will ever hit the same observer. The inverse square law also means that a potential observer would need to be in a relatively small radius from our system.

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Re:Which stars can see Earth as a transiting exoplanet? by rootusrootus on Wednesday October 27, 2021 @07:16PM (#29020256)

I hope that little forest of stars is not just dark, but actually empty.

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Re:Which stars can see Earth as a transiting exoplanet? by rimliu on Thursday October 28, 2021 @04:00AM (#29023547)

And those signals have travelled 60 light years. Our Galaxy is 100 000 ly accross…

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Re:Which stars can see Earth as a transiting exoplanet? by zardo on Wednesday October 27, 2021 @07:34PM (#29020442)

How far away will the signal be detectable above the background noise?

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