Visited the array of six radiotelescopes in Narabri recently. They combine to form one big telescope.
A lot of fascinating info.
Get this: Together they are so sensitive that they could pick up someone using a cellphone on Pluto! The electromagnetic footprint of any alien spacecraft entering our solar system would be millions of times more powerful than a cellphone on Pluto and since none of the radiotelescope arrays around the world has ever detected any such event in over 70 years of operation, it is safe to say we haven’t been visited by aliens in that time.
“ET go home!” No need. He never got here!