Space race: Is there anyone out there?

            I grew up in what was called “The Space Age,” which superseded “The Jet Age.” Living in a rural area with very little light pollution, I was able to marvel at the stars and planets, identify the constellations, and dream of discoveries of worlds beyond Earth. “The Space Race” was under way, pitting the United States, bastion of democracy and godliness, against the Soviet Union, that oppressively communist and atheistic regime that wanted to destroy America.

We had to win the Space Race, and I dreamed of being part of it. Twice I asked for a celestial telescope for Christmas. I still have the second of those telescopes, which allowed me to see the craters on the moon, count the moons of Jupiter, see the red dust of Mars, and ponder the rings of Saturn. I stayed up late in 1969 to watch “One small step for a man; one giant leap for mankind.”

Reports of UFOs — Unidentified Flying Objects — intrigued me, and I became convinced that the reports of other-worldly spacecraft were factual, indicating that beings from other planets were observing or perhaps trying to communicate with us.

As my career interests shifted from astronomy to writing, I grew less convinced about the reports of UFOs and less interested in astronomy (which, I had discovered, entailed a lot of mathematics).

So much has changed since the days when my elementary school gathered the entire student body to watch the launch of a Mercury astronaut. The simple mention of NASA no longer makes hearts flutter with excitement. We’ve been to the moon and might get no farther. Unmanned probes have explored Mars, but the obstacles to putting astronauts on Mars remain daunting. Planetary probes and fly-bys are interesting, but wouldn’t a cure for cancer be better?

The latest intriguing object in space is an anomalous visitor to our solar system that does not behave like any planet, asteroid or comet ever detected. Some scientists believe the object, which flew past Earth recently, might be an exploratory probe from a distant civilization, which might be checking out the civilization on Earth. This theory is being taken seriously by scientists.

Residents of Earth have been searching for signals from distant civilizations for generations. The SETI (Search for Extra-Terrestrial Intelligence) program has listened and watched for signals from other planets. Some of the biggest names in astrophysics, such as Stephen Hawking and Carl Sagan, have supported SETI. Simple odds seem to favor the existence of intelligent life somewhere out there.

“If you roll the dice so many times, and there are tens of billions of stars in the Milky Way, it is quite likely we are not alone,” Isaac Chotiner wrote in The New Yorker.

The odds certainly favor some form of life on distant worlds, but the chemical combinations to sustain life don’t seem to be common. The odds of basic life forms evolving into intelligent life capable of creating an interstellar probe seem prohibitively greater. Life on Earth defied extraordinary odds over billions of years. Suppose it’s a miracle and not an accident.

Even if we accept that SETI is scientifically valuable, the incomprehensible distances of interstellar and intergalactic space makes meaningful contact with extraterrestrial life impossible. A two-way conversation between Earth and another planet would be an intergenerational task. The closest stars with planets are dozens to hundreds of light years away. We would be waiting hundreds of years for a reply to our greeting, and that assumes that language barriers could be overcome. Einstein established that nothing can travel faster than light, so the “warp speed” dreamed up by “Star Trek” writers defies the laws of physics

Among the billions of stars in the Milky Way galaxy or the trillions in the thousands of other galaxies known to us, there might be intelligent life, but communicating with that civilization, much less visiting it, appears impossible.

Be awed at the vast heavens, the unfathomable distances, the varieties of objects and the enigmas of how it all came to be, but don’t count on spending your vacation on some distant world hundreds of light years away.

             

This article first appeared in The Wilson Times Feb. 2, 2019.

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Extra-terrestrial intelligence?

Last week, a group of scientists announced that they had identified more than 1,000 new "exo-planets" — planets orbiting stars other than our sun. The discovery of more than 2,000 such planets over the past few years has excited a lot of people who see these planets as harboring intelligent life or a livable environment for earthly humans to colonize after Earth has been depleted.

It appears that solar systems like our own are the norm for all of the billions of stars throughout our Milky Way galaxy and, presumably, among all the trillions of start in other galaxies. With so many planets orbiting so many stars, surely there are thousands, if not millions of exo-planets with life like our own planet's.

That's the thinking behind the Search for Extra-Terrestrial Intelligence (SETI). Both learned scientists and somewhat knowledgeable laymen dream of contacting intelligent beings on other worlds and even visiting and studying those other creatures populating our universe.

This thinking comes with a major "BUT ..." BUT ... any forms of life out there are so far away that we can never expect to visit them and probably can never hold a conversation with them. Our galaxy, the Milky Way, is estimated to be 100,000 to 120,000 light years across. A light year (the distance light travels in one year) is 6 trillion miles. The light we see in the night sky is light that is tens of years, even hundreds of years old. The light we cannot see (because it is too faint) is even older — many thousands of years old.

And that presents a problem for our goal of conversing with extra-terrestrial intelligent beings. Radio waves travel at the speed of light. If we were successful at discovering radio signals from our nearest neighbors outside our solar system, the radio message would be 4 to 10 years old upon arrival on Earth. Our SETI reply would take another 4 to 10 years to reach the other world. If no intelligent life was found around the first dozen (or hundred) closest stars, the search would continue on to worlds that are within dozens or hundreds of light years away and then to those thousands of light years away. Communication would be, at best, an inter-generational effort.

As for direct contact — traveling to distant worlds — just visiting planets within our solar system requires interplanetary travel lasting years. No one knows whether humans can endure such a trip either physically or psychologically. Would you take on a mission to Jupiter's moons, for example, knowing that you (and your family and friends) would have aged 20 years or more on the trip, even if you dodged the solar radiation and small asteroids that could destroy your space ship?

Travel to planets outside our solar system would be totally unfeasible, despite the dreams of "Star Trek" and other science fiction. "Star Trek" imagines vehicles that travel faster than the speed of light. Einstein theorized that nothing can travel faster than light, and no scientist has found a way around Einstein's barrier. Inter-galactic travel cannot be done.

So why are we so intent on finding extra-terrestrial intelligence? We're a curious species and want to know. But any discovery is likely to be a disappointment, perhaps a signal originated from a distant world whose inhabitants have gone extinct or whose world has been swallowed by a dying star.