Blasting out Earth’s location with the hope of reaching aliens is a controversial idea – two teams of scientists are doing it anyway
If a person is lost in the wilderness, they have two options. They can search for civilization, or they could make themselves easy to spot by building a fire or writing HELP in big letters. For scientists interested in the question of whether intelligent aliens exist, the options are much the same.
For over 70 years, astronomers have been scanning for radio or optical signals from other civilizations in the search for extraterrestrial intelligence, called SETI. Most scientists are confident that life exists on many of the 300 million potentially habitable worlds in the Milky Way galaxy. Astronomers also think there is a decent chance some life forms have developed intelligence and technology. But no signals from another civilization have ever been detected, a mystery that is called “The Great Silence.”
While SETI has long been a part of mainstream science, METI, or messaging extraterrestrial intelligence, has been less common.
I’m a professor of astronomy who has written extensively about the search for life in the universe. I also serve on the advisory council for a nonprofit research organization that’s designing messages to send to extraterrestrial civilizations.
In the coming months, two teams of astronomers are going to send messages into space in an attempt to communicate with any intelligent aliens who may be out there listening.
These efforts are like building a big bonfire in the woods and hoping someone finds you. But some people question whether it is wise to do this at all.
The history of METI
Early attempts to contact life off Earth were quixotic messages in a bottle.
In 1972, NASA launched the Pioneer 10 spacecraft toward Jupiter carrying a plaque with a line drawing of a man and a woman and symbols to show where the craft originated. In 1977, NASA followed this up with the famous Golden Record attached to the Voyager 1 spacecraft.
These spacecraft – as well as their twins, Pioneer 11 and Voyager 2 – have now all travelled well past the orbits of the outer planets. But in the immensity of space, the odds that these or any other physical objects will be found are fantastically minuscule.
Electromagnetic radiation is a much more effective beacon.
Astronomers beamed the first radio message designed for alien ears from the Arecibo Observatory in Puerto Rico in 1974. The series of 1s and 0s was designed to convey simple information about humanity and biology and was sent toward the globular cluster M13. Since M13 is 25,000 light-years away, you shouldn’t hold your breath for a reply.
In addition to these purposeful attempts at sending a message to aliens, wayward signals from television and radio broadcasts have been leaking into space for nearly a century. This ever-expanding bubble of earthly babble has already reached millions of stars. But there is a big difference between a focused blast of radio waves from a giant telescope and diffuse leakage – the weak signal from a show like “I Love Lucy” fades below the hum of radiation left over from the Big Bang soon after it leaves the solar system.
Sending new messages
Nearly half a century after the Arecibo message, two international teams of astronomers are planning new attempts at alien communication. One is using a giant new radio telescope, and the other is choosing a compelling new target.
One of these new messages will be sent from the world’s largest radio telescope, in China, sometime in 2023. The telescope, with a 1,640-foot (500-meter) diameter, will beam a series of radio pulses over a broad swath of sky. These on-off pulses are like the 1s and 0s of digital information.
The message is called “The Beacon in the Galaxy” and includes prime numbers and mathematical operators, the biochemistry of life, human forms, the Earth’s location and a time stamp. The team is sending the message toward a group of millions of stars near the center of the Milky Way galaxy, about 10,000 to 20,000 light-years from Earth. While this maximizes the pool of potential aliens, it means it will be tens of thousands of years before Earth may get a reply.
The other attempt is targeting only a single star, but with the potential for a much quicker reply. On Oct. 4, 2022, a team from the Goonhilly Satellite Earth Station in England will beam a message toward the star TRAPPIST-1. This star has seven planets, three of which are Earth-like worlds in the so-called “Goldilocks zone” – meaning they could be home to liquid and potentially life, too. TRAPPIST-1 is just 39 light-years away, so it could take as few as 78 years for intelligent life to receive the message and Earth to get the reply.
Ethical questions
The prospect of alien contact is ripe with ethical questions, and METI is no exception.
The first is: Who speaks for Earth? In the absence of any international consultation with the public, decisions about what message to send and where to send it are in the hands of a small group of interested scientists.
But there is also a much deeper question. If you are lost in the woods, getting found is obviously a good thing. When it comes to whether humanity should be broadcasting a message to aliens, the answer is much less clear-cut.
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Before he died, iconic physicist Stephen Hawking was outspoken about the danger of contacting aliens with superior technology. He argued that they could be malign and if given Earth’s location, might destroy humanity. Others see no extra risk, since a truly advanced civilization would already know of our existence. And there is interest. Russian-Israeli billionaire Yuri Milner
has offered One of the most consequential stories in American religion in recent years is the rapid and seemingly unceasing rise of “nones” – those who respond to questions about their religious affiliation by indicating that they are atheists, agnostics or “nothing in particular.” According to some recent estimates, around 4 in 10 millennials and members of Gen Z, a group that comprises those born after 1980, do not identify with a religious tradition. In comparison, only about a quarter of baby boomers indicate that they are religiously unaffiliated. Social scientists are only beginning to explore the demographic factors that drive individuals who no longer feel attached to a religious tradition. But as someone who follows the data on religious trends, I note one factor appears to stand out: gender. Scholars have long noted that atheism skews male. Meanwhile, critics have pointed toward the apparent dominance of male authors in the “new atheism” movement as evidence of a “boys club.” Indeed, a quick scan of the best-selling books on atheism on Amazon indicates that almost all of them are written by male authors. According to data from the Nationscape survey, which polled over 6,000 respondents every week for 18 months in the runup to the 2020 election, men are in general more likely than women to describe themselves as atheists, agnostics or nothing in particular. The survey, conducted by the independent Democracy Fund in partnership with the University of California, Los Angeles, was touted as one of the largest such opinion polls ever conducted. However, tracking the gender gap by age reveals that at one point the gap between men and women narrows. Between the ages of 30 and 45, men are no more likely to be religiously unaffliated than women of the same age. But the gap appears again among older Americans. Over the age of 60, men are 5 to 8 percentage points more likely to express no religious affiliation. Moreover, older Americans – both men and women – tend to be far less likely to identify as “nones” compared with younger Americans, according to respondents of the survey. What may be driving this pattern of young women and older women being less likely to identify as nones than their male counterparts? One theory in social science called the “life cycle effect” argues that when people begin to marry and have children, some are drawn back into religious circles to raise their kids in a religious environment or to lean on support structures that religion may provide. But once kids grow up and leave the house this attachment fades for many. I make this point in my forthcoming book called “The Nones.” The data on gender and those with no religious affiliation could indicate that this drifting is especially acute for men. One explanation could be that men are more likely to be religious when they are part of a family unit, but when children grow up, that connection becomes weaker. Unfortunately, the survey does not offer a direct test of this hypothesis. But it would fit with survey research over the past five decades that has consistently found that Christian women are more likely than men to attend church. One word of caution about the data is necessary. The survey is just a single snapshot of the public in 2019 and 2020. It’s possible that this same pattern would look different if data were collected 20 years ago or 20 years from now. Either way, it offers a small window into how age and gender interact with the religious lives of Americans. [Insight, in your inbox each day. You can get it with The Conversation’s email newsletter.] This article is republished from The Conversation, a nonprofit news site dedicated to sharing ideas from academic experts. It was written by: Ryan Burge, Eastern Illinois University. Read more:
The ‘life cycle’ effect
Ryan Burge does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
