Columnist Leonard David

Contact with ET: How would humanity react?

The Allen Telescope Array in Northern California is dedicated to astronomical observations and a simultaneous search for extraterrestrial intelligence (SETI).
The Allen Telescope Array in Northern California is dedicated to astronomical observations and a simultaneous search for extraterrestrial intelligence (SETI). (Image credit: Seth Shostak/SETI Institute)

The announcement that we have discovered alien life, if indeed it ever comes, would be one of the biggest moments in human history. And the ripple effects would be huge as well.

Unidentified flying object (UFO) organizations and specialists have been calling for "full disclosure" that alien contact has already occurred and could even be underway now, given highly publicized recent reports of UFOs — or unidentified aerial phenomena (UAP), as they've been rebranded — spotted by U.S. military pilots.

Meanwhile, powerful observatories like NASA's new James Webb Space Telescope are giving us highly detailed looks at the universe. Eventually, such data could tell us that Earth is not the only inhabited planet — perhaps, even, that life is common throughout the cosmos. 

That knowledge would likely have far-reaching effects on our view of ourselves and our place in the universe. Researchers are looking into the potential psychological impacts of such an announcement, which some people might have a hard time accepting.

Related: The search for alien life (reference)

Wanted: pertinent technical info

Carol Cleland is a professor in the Department of Philosophy at the University of Colorado, Boulder. She is also director of the university's Center for the Study of Origins and a SETI (Search for Extraterrestrial Intelligence) Institute affiliate.

Cleland thinks it is very premature to say that Earthlings have had contact with E.T., especially since we don't have the unredacted technical information about the behavior of UAPs supposedly buzzing about in our airspace. 

"All we have are some subjective summaries that have been sensationalized," Cleland said. "Harvard's Galileo Project is a secular attempt to acquire the pertinent technical information to address this question scientifically."

Immediate future

Heading that Galileo Project initiative is astrophysicist Avi Loeb of Harvard University.

Loeb said that previous protocols for possible contact with extraterrestrial intelligence were mostly inspired by the possibility of detecting radio signals from planetary systems around distant stars. 

"Given that the nearest star system, Alpha Centauri, is 4.4 light-years away, such signals would require a decade or more for a round trip conversation. As a result, they do not bear consequences to our immediate future," he told

But a different type of contact could deliver a prompt impact, Loeb said. "It concerns physical objects from another civilization that are already within the solar system. The arriving hardware need not be brainless but could possess artificial intelligence (AI) — seeking information about the habitable region around the sun, our backyard."

Contact protocol

The stated goal of the Galileo Project is to bring the hunt for possible signatures of alien technological civilizations from "accidental or anecdotal observations and legends" to the mainstream of "transparent, validated and systematic scientific research," according to its website

As part of that work, the Galileo Project aims to identify the nature of UAP.

The Galileo Project is designing and employing high-tech gear in a search for possible extraterrestrial equipment near Earth. An encounter with such objects would enable instant contact without a significant delay in communication time, Loeb said. 

"The potential for an immediate engagement changes the response protocol relative to a delayed radio signal, just as it does for an in-person meeting compared to a letter which is delayed by surface mail," he said.

Loeb pointed out that there is no current international agreement on how humanity should engage with a visiting object of extraterrestrial origin. It would be prudent to formulate such guidelines before they are needed, he added. 

Related: 13 ways to hunt intelligent aliens

Decision tree

"Any engagement could have implications for the future of humanity and should not be left to the spontaneous whims of a small team of researchers," Loeb said. "Since this is an international matter, the United Nations has the responsibility for formulating the contact protocol."

The safest course of action would be to use passive instrumentation to collect as much data as possible about any objects of interest, Loeb advised. This would include monitoring their response to unrelated human activities.

"Given this information, we should weigh the risks and benefits that will result from different engagements," he said. "The decision tree on how to proceed will have branches that depend on the objects' properties and behavior. Since it is difficult to forecast these unknowns in advance, decisions will have to be reached in real time."

Cultural boundaries

"What do we know about alien life today? Nothing," said Linda Billings, a consultant to NASA's Astrobiology Program and Planetary Defense Coordination Office.

"Some scientists believe that single-celled life must exist, or must have existed, somewhere else in our solar system," Billings said. 

"Some believe that life must have evolved elsewhere in the universe. Some believe life must be common throughout the universe," she added. "Some believe intelligent life must have evolved elsewhere. Some believe in, hope for, a universe teeming with intelligent life. Believe is the correct word here, not knowing."

Public opinion research provides at best a faint indicator of what everybody else thinks, believes and hopes for with regard to extraterrestrial intelligent (ETI) life, Billings said, and barely begins to probe differences in thinking and belief across cultural boundaries. 

"Our thinking about ETI to date has been largely anthropocentric, ethnocentric, Western-centric," she said.

Pile of assumptions

Billings said that SETI currently rests on a pile of assumptions, most notably that extraterrestrial life will have evolved the same way that life has evolved here on Earth. Also, it generally assumes that "advanced" alien life will have developed intelligence similar to human intelligence. 

In addition, Billings continued, SETI scientists assume that intelligent extraterrestrial beings will have developed the same kinds of technologies that humans have, and that these beings will be as curious about the possibility of intelligent life beyond their star system as we are. 

"These are assumptions, not facts," said Billings. 

"As to the consequences of human contact with extraterrestrial intelligence — and, again, the assumption here is that humans would be able to recognize and communicate with it — I am not at all convinced that such an event would be world-changing," she said. "It's a common claim, with no evidence to back it up. In addition, it's not possible to predict how, when and where contact might be made … The cultural conditions under which such an event might occur are, and will remain, unknown."

Code cracking 

Loeb sees things differently.

First of all, in order to avoid catastrophic misinterpretations as in the "Trojan Horse" story from ancient Greek mythology, Loeb said that data must be analyzed carefully within the broadest possible mindset. 

Deciphering the intent of intelligent extraterrestrial equipment may resemble the challenge of breaking the code of an encryption device, Loeb said, pointing to the film "Arrival" as an example. In that 2016 sci-fi drama, a linguist works with the U.S. military to communicate with alien lifeforms.

What would be required is a team of linguists and computer scientists, doing work resembling that led by Alan Turing in breaking the Nazis' Enigma code during World War II, said Loeb. 

"We might need to rely on our AI systems in figuring out the intent of extraterrestrial AI systems," Loeb said.

A still from the 2016 sci-fi film Arrival.” In the movie, 12 alien spaceships land on Earth in different locations around the globe.

A still from the 2016 sci-fi film "Arrival." In the movie, 12 alien spaceships land on Earth in different locations around the globe.  (Image credit: Paramount Pictures)

Out of Africa, out of Earth?

A proper interpretation of prompt contact with extraterrestrial technologies, Loeb said, could bring about "the most significant advance in our understanding of the reality around us in the entire history of humans." 

What is more, Loeb senses, this new understanding could have major consequences for our future aspirations in space.

"Our historic migration out of Africa started about 100,000 years ago," said Loeb, "but our future migration out of Earth may be triggered by a dialogue with a messenger from afar that does not resemble anything we had seen before." 

Editor's note: This story was updated at 7:45 p.m. EDT on Sept. 27 to clarify Carol Cleland's affiliation. She — not the University of Colorado, Boulder's Center for the Study of Origins — is a SETI Institute affiliate. 

Leonard David is author of the book "Moon Rush: The New Space Race," published by National Geographic in May 2019. A longtime writer for, David has been reporting on the space industry for more than five decades. Follow us on Twitter @Spacedotcom or on Facebook.

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Leonard David
Space Insider Columnist

Leonard David is an award-winning space journalist who has been reporting on space activities for more than 50 years. Currently writing as's Space Insider Columnist among his other projects, Leonard has authored numerous books on space exploration, Mars missions and more, with his latest being "Moon Rush: The New Space Race" published in 2019 by National Geographic. He also wrote "Mars: Our Future on the Red Planet" released in 2016 by National Geographic. Leonard  has served as a correspondent for SpaceNews, Scientific American and Aerospace America for the AIAA. He has received many awards, including the first Ordway Award for Sustained Excellence in Spaceflight History in 2015 at the AAS Wernher von Braun Memorial Symposium. You can find out Leonard's latest project at his website and on Twitter.