Apr 20, 2017
Cosmos Recap: Live Forever Or Die Trying
For this week’s episode of Cosmos, “The Immortals,” Neil deGrasse Tyson has got us thinkin’ ’bout eternity — or at least the transmission of messages through time and space. (It’s a nice tie-in to last week’s episode, which closed with all that communications tech bringing the world together.) The episode begins with an animation of ancient Uruk — Iraq — and the Akkadian priestess Enheduanna, the first person known to have signed her name to a piece of writing (Rand Paul probably plagiarized from her, too). We also get a capsule description of the Epic of Gilgamesh and his quest for immortality, including a retelling of the Flood story told to Gilgamesh by the wise Utnapishtim, an Ark story that predates the Genesis account by a millennium. We can look forward to an Answers in Genesis rebuttal that Tyson has it backwards: Gilgamesh, though merely a fable, confirms the reality of the Genesis flood. Tyson’s point, of course, is that narratives are just one form of immortality, “a story sent from one civilization to another across thousands of years.”
Ah, but what is the genetic code but the story of how “life itself sends its own stories across billions of years”? And we’re back to DNA, a story “written by nature and edited by evolution, the instructions for running and reproducing the intricate machinery of life.” And where did the message originate? “Nobody knows,” says Tyson, but he gives us a quick review of the likely possibilities — that life on Earth began in a shallow warm ocean, or perhaps near a deep-sea volcanic vent, or that life hitchhiked to Earth on a meteorite. To explain that possibility, we get an animation of the 1911 strike of a meteorite in Nakhla, Egypt, a meteorite later determined to have come from Mars. Did someone say Mars? Better cue up a clip of Carl Sagan telling us what we learned about the composition Martian atmosphere from the Viking landers in 1976: and voila — the gases trapped inside the Nakhla meteorite had exactly the same signature. And as we go to the first commercial break, we get a shaky shot (as if seen by a robotic probe’s camera) of Neil deGrasse Tyson standing on Mars. Without a spacesuit, which we think is ill advised.
Just to avoid any confusion, and in the interest of full disclosure, Tyson dutifully tweeted when the program aired,
We didn’t actually film on Mars. That’s what Director @BrannonBraga told me to say to you all.
Carl Sagan never had to say that, did he?
In front of a greenscreen re-creation of a crater on Mars, Tyson tells us that at some point, millions of years ago, the planet was hit by an asteroid the size of the Rock of Gibraltar, ejecting debris into space, where a chunk of the debris eventually was nudged into a collision course with Earth, coming down in Nakhla in 1911. Then, a quick reminder that rocks are porous, and can contain microbes; furthermore, some microbes have managed to stay alive quite happily in the vacuum, extreme temperatures and radiation of outer space. Further, terrestrial microbes from the Antarctic have been revived after being frozen for some eight million years. If life can survive such extremes, then it’s a good bet the it could, conceivably, travel from one planet to another in spaceborne debris. For that matter, Tyson says, it’s likely that early microbial life on Earth may have evolved, then been blasted into space by asteroids that wiped out most or all life on the planet, then fallen back to the surface, repopulating the earth after the planet cooled again.
So if life can conceivably travel from planet to planet, what about microbes traveling from one star to another? Longer time, greater distance, but again, not impossible, says Tyson, and thanks to all the time I’ve spent reading Creationist nonsense, I can see the smiles at the Discovery Institute. Mere speculation! No evidence! Not in the Bible! Leaving them aside, we move on to an animation of the Milky Way, and a “plausible scenario for how life could spread from one solar system to another,” all to the accompaniment of Ravel’s Bolero (but sorry, no Bo Derek). As our solar system moves through the Milky Way, completing one orbit of the galactic center every 225 million years, it passes through clouds of gas, the birthplaces of new stars and planets. As we move through, the cloud’s gravity will affect the comets at the outer edges of our solar system; some of those comets will be nudged into a collision with the inner planets, striking the Earth and ejecting microbe-filled rocks, which then may fall to the surface of one of the newly-formed planets in the cloud. Repeat the process over billions of years, and you’ve got life hopping from solar to system to solar system. Voila, panspermia.
But if there is an abundance of intelligent life in the universe, how do we find it? Tyson tells us about Project Diana, the first experiment in bouncing radar off the moon, in 1946. The radio waves went out to the moon, and part of them were reflected back — but the other parts kept on going, out at the speed of light, and were followed by years of television broadcasts, FM radio, radar, and other high-powered signals, beaming into space. After 70 years, the first of those radio signals have reached other planets, some of them, maybe, inhabited. Tyson then addresses the problem of actually detecting a hypothetical alien world’s communications — it all depends on listening at the right moment, to the right frequencies, at the right part of the sky. And then you have to factor in time — the possibly brief period when a civilization is using a technology that we could detect. Already, as television has switched from analogue to digital broadcasting, we’ve made it less likely that aliens who may have enjoyed I Love Lucy to catch the ending of How I Met Your Mother. If aliens are communicating with some form of communication we haven’t thought of, “their messages could be swirling all around us at this very moment, but we lack the means to perceive them.”
For that matter, there’s no guarantee that any civilization would live long enough to contact us. Civilizations come and go, dying off due to any number of factors — droughts, wars, invasions, plagues, and so on. Tyson presents a cheery litany of catastrophes that could wipe out our civilization — a nearby star’s going supernova (fortunately, we’re far enough away from any likely candidates); an eruption of a supervolcano like the one some 70,000 years ago in Toba, Sumatra; an asteroid hitting the Earth — though technology we have today could probably deflect a life-extinguishing asteroid, provided we detect it in time. And then there are the indigenous American civilizations that were wiped out by European visitors — not the conquistadors, but their germs. 9 out of 10 Native Americans died of diseases without ever coming into contact with a European person.
And then there’s self-destruction: Says Tyson, all our economic systems are geared toward short-term exploitation of resources, fast growth, and profit. He’s going to make Fox News mad, even though he’s talking about all industrial systems, not just American capitalism. There’s no real incentive for cooperation and sustainability. And yes, it’s time to talk about climate change again — now, Tyson walks on a sand dune, and the juddering camera of the Mars probe returns, perhaps suggesting that our own planet may be headed for an atmosphere as inhospitable to big mammals as Mars’s. Still, if we have anything going for us as a species, it’s our big ape brains, the intelligence and clever adaptability that has always given us an evolutionary edge. Our intelligence is imperfect, he says, and we’ve certainly fallen for some terrible leaders (tape of Mussolini, Hitler), but if we can also produce a Gandhi, a King, a Malala Yousafzai, a Mandela, then we’ve got a pretty good chance.
The episode’s final segment returns to the Cosmic Calendar metaphor, imagining what we might do in the first few minutes of the next cosmic “year” — if we get our act together, at least, and learn to respect our pale blue dot of a home. In the first tenth of a second, maybe we can kick fossil fuels, so that “for the next cosmic minute and a half — 40,000 years,” the Earth will continue to support us, with a temperate climate. And then Tyson reprises one of the lovely narrative sequences from the original series, as the visuals shift to a terraformed Mars, and a huge spaceship setting sail — literally, on the solar wind — for beyond the solar system. And since you just can’t go wrong with a Carl Sagan clip, here’s the master’s version of the same optimistic “we humans are capable of greatness” speech:
Cosmos: A Spacetime Odyssey airs on Fox 9:00 Sundays Eastern/Pacific, 8:00 Central/Mountain. Reruns Monday on National Geographic Channel 10:00 Eastern. Episode 11, “The Immortals,” online at CosmosOnTV.com
Program note: No Cosmos next week; in two weeks, the penultimate episode, “The World Set Free,” is devoted largely to the reality and challenges of climate change.