A researcher says that that’s because “space is really, really big”:
A radio telescope in outback Western Australia has completed the deepest and broadest search at low frequencies for alien technologies, scanning a patch of sky known to include at least 10 million stars.
Astronomers used the Murchison Widefield Array (MWA) telescope to explore hundreds of times more broadly than any previous search for extraterrestrial life.
The study, published today in Publications of the Astronomical Society of Australia, observed the sky around the Vela constellation. But in this part of the Universe at least, it appears other civilisations are elusive, if they exist…
“With this dataset, we found no technosignatures — no sign of intelligent life.”
Professor Tingay said even though this was the broadest search yet, he was not shocked by the result.
“As Douglas Adams noted in The Hitchhikers Guide to the Galaxy, ‘space is big, really big’.”
“And even though this was a really big study, the amount of space we looked at was the equivalent of trying to find something in the Earth’s oceans but only searching a volume of water equivalent to a large backyard swimming pool.
“Since we can’t really assume how possible alien civilisations might utilise technology, we need to search in many different ways. Using radio telescopes, we can explore an eight-dimensional search space.
International Centre for Radio Astronomy Research, “Australian telescope finds no signs of alien technology in 10 million star systems” at ScienceDaily
Space is not as big as the human imagination though.
Paper. (open access)
See also: Seven reasons (so far) why the aliens never show up. Some experts think they became AI, some that they were killed by their AI, and others say they never existed. Who’s most likely right? Science fiction writer Matt Williams delves into seven hypotheses into which scientists and science fiction writers have put a lot of thought.