Breaking The Great Silence

Cosmologists often speak of The Great Silence. If the prospects for extraterrestrial life are so high in the vastness of the Universe, why aren’t we hearing anything from any of our neighbors?
At the risk of sounding an unwarranted note of paranoia, it is possible our neighbors do not want us to know they are there. Stephen Hawking, before he died, sounded a warning against broadcasting our existence. He urged caution about “shouting in the jungle” before we know what may be lurking in the trees.
It’s a reasonable concern, but not, in my opinion, a particularly cogent one. Any alien life forms are far away, very far away, and they are faced with the same physical limitations as us.
But we could be pen pals, and very likely will be soon.
SETI (Search for ExtraTerrestrial Intelligence has been turning an ear skyward since 1992. You may have seen the 1997 science fiction movie starring Jodi Foster. SETI listens, but does not broadcast.
Of course, we have been broadcasting radio and television signals for over a century. Few of those signals would indicate an intelligent life form on our planet, and they are thought to be swallowed up fairly quickly by cosmic background noise.
A more targeted and sustainable signal, The Arecibo Message, was broadcast from the Arecibo Observatory in 1974. Bound for a Globular Cluster named Messier 13, it will arrive there in 25,000 years.
In 1999, The Cosmic Call was broadcast to several stars in relatively close proximity, scheduled to arrive at their destinations from 2051 to 2069.
In 2017, METI (Messaging ExtraTerrestrial Intelligence) sent a combination of math and music to GJ 273 (Luyten’s Star). It will arrive there in four years (2029), a journey of only 12 years.
In 2022, METI sent the Periodic Table, some music, and some environmental data to Trappist 1. It will arrive in 2061.
Double the sending times to arrive at the earliest possible return messages.