The 10 Percent We Can See

The Hubble Space Telescope has made it possible for humanity to look further into the past through time and space than a lot of other tools, and it's just recently been used to determine that the observable universe contains just ten percent of all the galaxies that exist1. More than this, recent studies have shown that the early observable universe itself contains ten times the number of galaxies than previously estimated. Considering the sheer size of the cosmos, these numbers are absolutely mind blowing. With roughly 2-trillion galaxies to explore, each with millions or billions of stars of their own, we will likely have enough new places to study and explore until the last starts in the universe grow cold and dark.

A Fraction of the Visible Universe

When I think about the numbers involved in space exploration, I can't help but feel that humanity is a small and insignificant accident in the grand scheme of things. This single planet has been home to billions of different forms of life, and quadrillions of individual lives if not more. Given the richness of life on this world, it only makes sense that life must exist in other forms on other celestial objects. If we were to assume that two trillion galaxies each contained a quarter-billion stars and each star had an average of 3 planets orbiting them, we'd be looking at around 1,500,000,000,000,000,000 planets. That's 1.5-sextillion worlds. Could life have evolved on just this one? I'd like to hope not.

But I have had conversations with people who steadfastly believe that life only exists on the Earth and that we are special because God chose to create us and only us. So far as I know, there are no religious texts that explicitly talk about life on other worlds. What if we are the only sentient beings in the universe? What if this planet is the sole home to all life in the universe? What would this ultimately mean when humanity begins to expand into the universe? Would it mean anything at all?

If it's determined after an indeterminate number of eons that humans are the only sentient forms of life in the universe, we will likely be at a point technologically and societally that it will no longer matter. Colonies would have existed on various worlds for an incredible amount of time, and the people from those colonies would have their own unique languages, customs, traditions, and genetic differences. Given enough time, there would be various branches of humanity as a result of cosmic radiation or intentional eugenics programs making changes to our DNA. We'll begin to see different types of human. Going further still, there will be communities of people who have completely separated from existing societies to create their own worlds. These people, over time, would evolve in various ways to become completely alien to other groups of future humans.

Ultimately, if it's proven that there is no other life to be discovered in the universe, our descendants will become that life for other descendants to learn about. The universe is a vast, vast place. So large that our minds will likely never truly understand or appreciate its scale and complexity. And that's completely okay. It's there for us to explore. I just hope that, when we do find new life and new civilizations out there — human or otherwise — we greet them with open arms and open minds.


  1. To the best of our knowledge, anyway.

Hello Universe?

A friend passed along a Time Magazine article discussing extraterrestrial life, and the odds of us ever knowing about its existence. According to Jeffery Kluger, the author, people who are concerned about aliens coming to the Earth with their superior technologies in a bid to conquer the planet and subject us all to an eternity of slavery have nothing to fear. On the flip side, people who are looking forward to the day when aliens come to Earth with their superior technologies in a bid to open relations and help us grow as a species will have to wait a very, very, very, very long time.

One of the key arguments Kluger employs involves numbers. Big numbers:

Humans and aliens haven't connected yet, but with 1022 stars out there (that's 1 with 22 zeros), it's just a matter of time — right? Wrong. If exobiologists have learned anything, it's that you and your kids and their kids' kids will probably never hear the slightest peep from an alien. If E.T. the movie star is your idea of what extraterrestrial life might be like, you will be disappointed. If your thoughts run more to War of the Worlds, you can breathe easy.

I don't know about "breathing easy" because, if our galaxy had sentient life on only one planet, it would be incredibly saddening. Going further, if the entire universe was devoid of intelligent life outside of Earth, it would be devastating. An entire cosmos for the exclusive of life forms from one tiny spec of a planet in the rural backwater of one unremarkable spiral galaxy? Even if humanity were to spread out to every habitable (or semi-habitable) planet and evolve into a thousand unique variations of Homo Whatever, develop new languages, new cultures, new stories, new religions, new understandings … the universe would be a very predictable place.How boring.We Won't Stop, 'cause We Can't StopThe author of the Time article seems to say that we will never meet E.T. due to the difficulties we currently face communicating long distances with species that may or may not be using similar types of technology. Will other intelligent beings use radio, which is limited to the speed of light? Will they be at our technological level by the time our messages reach them? Will they be beyond our technological level and not even realize a people with "ancient" technology are reaching out to them? Are our closest celestial neighbors able to communicate through a telepathic link that is not bound by distance, thus making technologies like radio less important?Who knows? But this is part of the fun and challenge involved with making the first tentative steps off our world and outside of the solar system.There are several problems with saying that we will never, ever, ever come into contact with a group of people from regions unknown, such as how long an intelligent civilization can survive. Humans have (apparently) been around on the Earth for over a million years, but many of our technological advances have occurred over the last five thousand. We've had the ability to talk to people through radio waves for over a century, and the technology has seen exponential growth in that time. Over the last 5,000 years our species has faced numerous technological setbacks due to wars, disease, religious interference, and natural disasters. Skills lost. Civilizations in ruins. Lessons forgotten.Who is to say the same thing can't happen elsewhere in the cosmos? The universe is a very big place.But the inverse could also be true. A civilization may have sprung up on another world 20,000 years ago and enjoyed incredible success, never once facing self-annihilation like we humans have come close to on several occasions. These people could have learned the from the pointlessness of war and explored their galactic neighborhood in the name of peaceful exploration. They could have stumbled across our signals, come in for a closer look, and deemed us not yet ready for contact.Who is to say this isn't happening somewhere in the cosmos? The universe is a very big place.TimeKruger ends his article with an unfortunate-sounding sentence:

Too bad — or maybe very good — you're never going to see them.

Really? Never? That's a very strong word to use. Many very intelligent people said that we would never explore the entire planet, but we did. Many very intelligent people said that we would never learn how to fly, but we did. Many very intelligent people said that we would never set foot on the moon, cure certain diseases, or do any number of other very difficult tasks … but we did. Not only did we overcome these challenges, but we overcame them with zeal.Who is to say this won't happen sometime in the future? We know so very little about our little corner of the Milky Way Galaxy, and even less about what lies beyond. The universe is a very big place.