RE: No ET! Ever?
February 18, 2017 at 1:00 pm
(This post was last modified: February 18, 2017 at 1:03 pm by Jehanne.)
(February 18, 2017 at 7:11 am)Mr Greene Wrote: I did hear one estimate of there being 1,000,000 civilized species in the Milky Way.
Even if there were that many each would have on average over a 100 cubic light-years to inhabit without encroaching on another.
As for where to point an antenna; the Galactic plane would seem like a reasonable start.
But, they would be pointing it at a moving target that is going at 675 times the speed of sound, and then, they would also have to track that target across intergalactic space. In addition, the radio signal, even if it was a laser, could end-up being scattered away by the zillions upon zillions of atoms, molecules, dust particles, etc., scattered throughout intergalactic space. In addition, the energy requirements, given the inverse law, would still be enormous, likely, the entire energy output of the US over the course of a year, assuming, that ET wanted their signal to picked-up by something other than the Arecibo telescope, which means, of course, that Arecibo would need to be looking at the right spot at the exact time.
P.S. Arecibo is not equipped to pick-up laser light.