Over the last few decades, scientists and researchers have pondered the ultimate question: is there intelligent life out there in the Universe? And if so, where?
There are theories and postulates like the Fermi Paradox and the Drake Equation which explore the mathematics behind the probability of the existence of alien life. Questions like “Why haven’t we found them yet?” or Why haven’t we detected them yet?” arise.
Carl Sagan summed up the possibility:
“I’m frequently asked, “Do you believe there’s extraterrestrial intelligence?” I give the standard arguments- there are a lot of places out there, the molecules of life are everywhere, I use the word billions, and so on. Then I say it would be astonishing to me if there weren’t extraterrestrial intelligence, but of course, there is as yet no compelling evidence for it.
Often, I’m asked next, “What do you really think?”
I say, “I just told you what I really think.”
“Yes, but what’s your gut feeling?”
“But I try not to think with my gut. If I’m serious about understanding the world, thinking with anything besides my brain, as tempting as that might be, is likely to get me into trouble. Really, it’s okay to reserve judgment until the evidence is in.”
Today, with the proliferation of planet-hunting technology and satellites like Kepler and TESS, which are helping to discover planets that exist outside of our solar system, the question is becoming less “why” and more “where” when it comes to aliens.
Soon, NASA will be launching its James Webb Space Telescope to aid in this search and maybe determine if some of these planets have the conditions to harbor life.
One scientist, Dr. Rosanne Di Stefano of the Harvard-Smithsonian Center for Astrophysics, argues that we may one day find an intelligent alien civilizations living among star clusters at the far edges of our own Milky Way galaxy.
“A globular cluster might be the first place in which intelligent life is identified in our galaxy,” said Di Stefano.
These ancient globular star clusters could house up to millions of stars. Some of the oldest stars in the Milky Way can be found in these regions and can be as old as 10 billion years old. Some experts believe some may have been around since the birth of our galaxy. The age of these clusters has previously played an essential role in helping astronomers pinpoint the center of the Milky Way and aid in determining the age of the universe.
What determines the possibility of life’s existence in a star system? That would be Its “Goldilocks” or habitable zone.
This refers to a “just right” distance between the star and a nearby planet—which directly affects the average temperature and eventually the planet’s ability to produce liquid water. Brighter stars provide a larger potential habitable zone than their fainter counterparts but have a much shorter lifespan.
Habitable planets that could exist in these globular clusters would be huddled near dim red dwarfs and this is crucial because smaller orbits help protect those planets from the violent forces found in such a crowded galactic neighborhood—forces that could eventually push a smaller world into cold, interstellar space. Di Stefano claims that once these planets do form, “they can survive for long periods of time, even longer than the current age of the universe.”
Some of these clusters are packed to the brim and astronomers have estimated that some house up to a million stars that span a combined distance of up to 100 light-years. To give you an idea of how dense that is, our Sun’s nearest star is close to 4 light years away.
The main ideas drawn by this research include the high probability of the formation of potentially habitable worlds in a globular cluster due to the sheer volume of stars and that these worlds could survive for billions of years. This is important because complex life takes time to evolve and to develop the kind of intelligence needed to build and maintain a civilization—especially a space-faring one.
On Earth, cultures or nations that have had the ability to easily communicate and exchange ideas or resources with neighboring counterparts have evolved faster than those found in more remote areas. This same idea can apply to a planetary system. Our civilization as a whole is still in the early stages of exploring interstellar space—it was just three years ago that a man-made object, The Voyager spacecraft—breached the edge of our solar system.
According to this new research, a civilization that exists in a globular cluster would have a far more accelerated timeline in the progress of their exploration of neighboring systems. Their nearest star could be about 20 times closer to them than our nearest star is to us.
The difference is significant—a distance of 1 trillion miles in a cluster compared to 24 trillion miles in our neck of the woods. This could make interstellar travel and communication far easier for this possible civilization. “We call it the ‘globular cluster opportunity,’” says Di Stefano.
“Sending a broadcast between the stars wouldn’t take any longer than a letter from the U.S. to Europe in the 18th century.”