Earth is a noisy planet. Not with
sound waves, which never leave the atmosphere, but with all sorts of radio
noise. Between radar beams from weather monitoring stations, airports and
military use, TV and radio signals, and even deliberate attempts by astronomers
to send messages to any listening aliens, our planet constantly announces its
presence to the universe at large.
Because we are so radio noisy,
astronomers have for decades tried to find such radio signals emanating from
any other existing alien civilizations in our Milky Way, with little success.
In 1977, astronomers performing such a search with a giant radio telescope run
by Ohio State University detected a signal, a powerful radio burst, dubbed the
“WOW!” signal. It never appeared again despite much searching.
In 2015, billionaire Yuri Milner
donated $100M to create a program designed to search for extraterrestrial radio
signals, the Breakthrough Listen Project. The project uses the Parke Radio
Telescope in Australia, operated by the Commonwealth
Scientific and Industrial Research Organization.
Recently, news broke that the project detected
a narrowly-focused beam of 980 MHz radio waves detected in April and May 2019.
The signal came from the direction of our nearest stellar neighbor, Proxima
Centauri, which has two planets orbiting it, and one is Earthlike. That frequency
is important because human-made craft and satellites typically don’t use it,
lending credence to the possibility of it coming from an alien civilization.
Parke Radio Telescope, credit Commonwealth Scientific and Industrial Research Organization
The powerful burst excited
astronomers of the project. Sofia Sheikh, an astronomer at Penn State
University, led the analysis of the signal. While the team has yet to release
its full report, Scientific American interviewed Sheikh. She said, "It's
the most exciting signal that we've found in the Breakthrough Listen project
because we haven't had a signal jump through this many of our filters before.”
No repeat signal has been detected,
and the team still must rule any natural signals, such as a distant comet or
some other astronomical. But astronomers excitedly await the full report. We
may have finally discovered that we have neighbors.
Each month, I write an astronomy-related column piece for
the Oklahoman newspaper. On the following day, I post that same column to my
blog page.
This is reprinted by permission from the Oklahoman and www.newsok.com.