The Possibility of Finding Aliens
The world’s most famous theoretical physicist and cosmologist, Stephen Hawking, believes that alien life is almost certain to exist somewhere in the Universe other than on Earth. Nuclear physicist Enrico Fermi came to the opposite conclusion.
Writing in The Sunday Times (April 2010) Jonathan Leake says Hawking’s conviction is based on numbers: “The Universe, he points out, has 100 billion galaxies, each containing hundreds of millions of stars. In such a big place, Earth is unlikely to be the only planet where life has evolved.”
The possibilities seem almost infinite in the context of numbers concerning just our own galaxy, the Milky Way. According to universetoday.com, the Milky Way is “about 120,000 light years across ... has between 200 and 400 billion stars ... (and is considered) a middleweight” among galaxies.
Enrico Fermi’s Paradox
Hawking’s suggestion there may be alien life forms out there looking for kryptonite mines is not shared by all scientists.
A Nobel Prize winner, Professor Enrico Fermi had some thoughts on the probability of extraterrestrial life that ended in a puzzle that bears his name - The Fermi Paradox.
He reasoned that given the size and age of the Universe there should be many technologically advanced civilizations. However, there’s no evidence to support their existence.
In other words, it’s probable that we aren’t the only place in the Universe that has spawned intelligent life, but there’s no proof that it exists elsewhere. Why? One answer doesn’t bode well for our future: it’s been suggested that intelligent species are not rare in the Universe; they appear often, but end up destroying themselves through their scientific discoveries.
What Will Extraterrestrial Life Be Like?
For the sake of making an interesting story let’s assume Professor Hawking is right.
If alien life forms find us before we find them we have to assume they are smarter than us and have better technology.
We’d also better hope they are herbivores and that they are not like us – aggressive and violent.
It would be nice if they approach their new found world in the style of naturalist David Attenborough rather than that of the Trump sons who like to kill big game. If they have the attitude of Don Jr. and Eric they might just squash us as we squash irritating bugs.
Jonathan Leake quotes Hawking as saying “The real challenge is to work out what aliens might actually be like.” The scientist then goes on to suggest it’s most likely to be microbes or simple animals.
But, what if it’s intelligent life? If that’s the case, and Dr. Hawking allows that is a possibility, he suggests keeping a safe distance.
In a 2017 documentary called Stephen Hawking’s Favourite Places he says “One day, we might receive a signal from a planet … but we should be wary of answering back. Meeting an advanced civilization could be like Native Americans encountering Columbus. That didn’t turn out so well.”
He says he imagines intelligent aliens “might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach.”
Size of Universe Defies Extraterrestrial Search
If intelligent aliens haven't found us it may be because the Universe is not old enough.
The Guardian has reported that a Danish physicist has an explanation for the lack of contact. There simply hasn’t been enough time.
Researcher Rasmus Bjork, at the Niels Bohr Institute in Copenhagen, found that even if alien spaceships could hurtle through space at a tenth of the speed of light, or 30,000 km a second, - NASA’s Cassini mission to Saturn plodded along at 32 km a second - it would take 10 billion years, roughly half the age of the Universe, to explore just four percent of the galaxy.
More on a Human Scale
Those humongous numbers don’t daunt the folks at the Institute of Space Studies of Catalonia, Spain. They’ve got a project going with the catchy title “Sónar Calling GJ 273b.” This is a radio message with 33 musical pieces each just 10 seconds long, and information on the concept of time.
It has been beamed at a planet called GJ 273b (how do they come up with these memorable and romantic names?). They lobbed their broadcast into space in November 2017.
GJ 273b is only 12 light years away; in galactic terms that’s a single-ticket transit zone. If intelligent life exists on this planet, and they can tune out their top-40 stations long enough to pick up the signal, we might hear back in 24 years.
Ah but, what if we start thinking outside the space capsule?
Brian Greene, a professor of math and science at Columbia University has been doing just that. He says that time travel is theoretically possible (this is a minority opinion in the scientific community).
In a 2015 video produced for The Big Think, Professor Greene explains that time is an artificial construct of humans. “It allows us to organize our experiences into a coherent framework that allows us to survive.” Okay, that’s a bit complex and challenges the capacity of most of us to understand, but, suppose he’s right; isn’t it possible that some smarty-pants aliens have figured out how to travel through time?
Is a video released in December 2017 by the U.S. Defense Department telling us this may have happened? It records an encounter in 2004 between Navy jet pilots and – er – something.
Was this an advance scouting party from a time-travelling species of scaly critters? If so, why haven’t we heard from them since? Simple really. They probably concluded we are too primitive to waste their time investigating.
Seth Shostak is with the Search for Extra-Terrestrial Intelligence Institute. Speaking at a New York symposium on the future in the fall of 2017 he told his audience he was willing to “bet everybody a cup of coffee that we’ll find intelligent life within 20 years.”
In June 2009, Stephen Hawking held a party for time travellers and to ensure only the genuine article attended he didn’t announce it until after the event. He said it was “experimental evidence that time travel is not possible.” He was proven correct because no one showed up.
- “Don’t Talk to Aliens, Warns Stephen Hawking.” Jonathan Leake, Sunday Times, April 25, 2010.
- “So Much Space, so Little Time: Why Aliens Haven’t Found us Yet.” Ian Sample, The Guardian, January 18, 2007.
- “Stephen Hawking’s Universe.” Discovery Channel, April 2010.
- “We Just Sent a Signal to Make Contact with Aliens on a Distant ‘Super Earth’ — Here’s What we Said.” Rob Ludacer and Jessica Orwig, Business Insider, November 16, 2017.