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Cosmos with Cosmos Episode 6: Travellers' Tales

Voyager is the ultimate expression of our desire to explore

Posted by Casey Dreier

25-11-2013 15:56 CST

Topics: product review, history, fun, Voyager 1 and 2, Neptune, spacecraft, many worlds, Saturn, Uranus, Jupiter

Cosmos with Cosmos is a weekly series that encourages people to get together and watch Cosmos with a cosmo(politan) or drink of your choice. We're posting weekly episode recaps and discussion through February of 2014. This series is made possible by members of the Planetary Society. If you like what you're reading, please consider joining the Society or donating $10 to help support projects like this in the future. To learn more about this series and find out how to watch Cosmos, see our introduction.

« Episode 5:
Blues for a Red Planet

Episode 7: The Backbone
of Night »

Watch Cosmos Episode 6: Travellers' Tales on Hulu or iTunes.

Neanderthals didn't get around much. Beyond known settlements in Europe and eastern Russia, no signs of them have been discovered anywhere else. They seem to have lacked a certain zest for exploration and expansion.

Homo sapiens, on the other hand, spread to every niche and corner on the planet. We've gone beyond that, even, exploring the Moon and creating semi-permanent habitats in Earth orbit. Where technology or cost prevents us from going deeper into space, we don't give up - we send robotic emissaries in our place. There seems to be a powerful desire in our species to push outward and explore. This strange compulsion is what has "characterized and distinguished the human species" as Sagan says early in this episode. It's what led us to create missions like the Voyagers, which venture out in the immensity, never to return.

The Solar System Family Portrait


The Solar System Family Portrait
Voyager 1's last view, looking back on every planet in the solar system.

The neanderthals had no Voyager, no sailing ships, no great feats of exploration. They died out, along with every other humanish species, victims of climate change and competition with homo sapiens. Our species went on to conquer the planet. We created the the Voyagers and the other spacecraft that explore our solar system. Why us?

Episodes 6 of Cosmos, Travellers' Tales, doesn't try to answer this question. It chooses to celebrate the that the "the passion to explore is at the heart of being human." We all need reminders of this sometimes, especially these days, when our newfound security, wealth, and comfort work to dissuade us from the expense and risk of exploration - slowly seducing us to the same fate as poor homo neanderthalensis.

Travellers' Tales is a thematic sequel to episode 5's Blues for a Red Planet, though I think it works better as an hour-long piece of entertainment. Both Voyager and Viking could trace deep roots in our culture and common history. Both exemplified the best of us, representing a purity of vision. Unlike historical sailing missions of exploration, both Viking and Voyager were untainted by greed, war, disease, and conquest. Their missions were peaceful, their goals scientific. Voyager ultimately became the more famous of the two, I would argue. It revealed far more new, tantalizing worlds, stranger vistas, and continues to operate to this day. It also traces a greater lineage than Viking, which makes for a more profound story.

The show begins with a callback to our very first episode. We start outside and look in, traveling from the outer solar system towards the Sun, finding Earth (and ourselves) at the very end of the journey. But instead of jumping into history, Sagan takes us to the present (as it was in 1979, that is) with a look inside NASA's Jet Propulsion Laboratory, cigarette smoke and all, when scientists were receiving data as Voyager 2 flew by Jupiter in 1979.

The parallels are drawn heavy between the Voyagers and the sailing vessels of second great age of exploration, when Europe came to dominate much of the world. Both types of ships travelled great distances over many years, both explored new lands, and both returned tales of adventure and discovery. Unlike the sailors, though, the travellers' tales returned by Voyager are always true. There are no fanciful, mis-remembered mountains lurking in the haze of Titan or shimmering creatures seen after a rum-drenched night of staring into the clouds of Jupiter. Voyager only relayed the data with a cold sobriety, leaving us to our to our wits to spin the fanciful interpretations of worlds of ice and fire and shattered crust.

After a highlighting the Dutch enlightenment and their remarkably open, adventurous society, we get a brief glimpse at the great scientist Christiaan Huygens, who discovered Saturn's rings. We see his focused efforts to peer through the newly developed telescopes of the time, struggling to understand the new worlds he saw. We are then brought back to JPL, where we see another group of scientists struggling to understand the new worlds they saw, this time through Voyager's eyes. Our tools may have improved, but our desires to understand are the same.

These two spacecraft would continue to function far beyond when Sagan (or anyone) would have predicted. Just last year, I was part of The Planetary Society's 35th anniversary event celebrating the Voyager mission with its lead scientist, Ed Stone. Not only did Voyager 2 continue on towards Uranus and Neptune, but they both have continued on towards interstellar space. Both are still radioing back information, and Voyager 1 has now passed into interstellar space. While only a few instruments still function, they still carry with them the golden record, their welcome message, our species' way of saying, "we were here."

Svante Pääbo is the Director of the Max Planck Institute for Evolutionary Anthropology in Germany, where he specializes in sequencing the DNA of ancient creatures. He often asks himself the question of why humans were driven to explore and neanderthals were not.

There is a compelling argument that our drive to explore - Pääbo calls it our "madness" - is related a series of genetic mutations that are unique to humans. Variants of the gene DRD4, for example, have been linked to restlessness and risk taking, and Pääbo believes it represents the mutations that made us the type of species that looks across an endless ocean and thinks "let's see what's out there."

I don't think anyone seriously believes that our drive to explore is a work of a single gene, but I do see how a set of mutations of various genes could increase this tendency and thereby increase their likelihood for reproduction. By reaching out into new places, we exploit untapped biological niches for ourselves. We face animals that aren't evolved to hunt us. The flexible software of our brains could more quickly adapt to new surroundings, and in doing so the new surroundings would themselves select for our own adaptations that make us flexible. The drive for exploration and expansion in this sense can be considered a phenotype - the physical expression of a gene or set of genes in an organism.

But phenotypes don't just represent physical characteristics. Richard Dawkins expanded on the concept with his theory of the extended phenotype, which is any characteristic or expression in the world that helps in the survival of those genes, regardless of whether they are in the same body of the genes themselves.

Voyager 2 in the solar wind

NASA / GSFC Conceptual Image Lab

Voyager 2 in the solar wind
This artist's concept shows the venerable Voyager 2 spacecraft journeying out of the solar system at 15 kilometers per second (34,000 miles per hour) with the solar wind streaming past it four times faster.

Thought of in this way, the Voyagers are the ultimate extended phenotype of our species. A few mutated genes in the bodies of our ancient ancestors hundreds of thousands of years ago have found their expression in the hardened metal and golden plates of these spacecraft. Our expansionist, exploratory desires may be our most important evolutionary trait we have, maybe driving us off this planet and onto another, saving us from the vulnerable position our species finds itself in.

The neanderthals lacked this desire and they suffered dearly. Their genes didn't carry them out beyond much of anything. Our genes give us a predilection to explore, but we must consciously choose to do so. We've seen both in culture and in biology that uninquisitive, cautious groups die while the bold thrive. In which society would you rather live, one that looks out or one that looks in? As NASA budgets decrease and we find ourselves explaining away exploration as too costly, Sagan reminds us here that we owe it to ourselves to embrace the gift our genes bestowed upon us.

Science Updates

  • Basically the entire final sequence of the outer planets became out-of-date as Voyager continued on past Saturn to Uranus and Neptune. We've also had the benefits of Galileo orbiting Jupiter and Cassini orbiting Saturn, with the spectacular images sent back by the Huygens probe of the surface of Titan. The moons not only rains hydrocarbons - they collect into lakes!
  • Europa remains a focus of intense study, though no mission has yet been solely devoted to it. This may change in the next 10 years if NASA can fund the Europa Clipper mission to determine the characteristics of its subsurface ocean, which it sounds like they didn't know existed when this scene was filmed (how would they?).
  • Cassini, which Sagan mentions, arrived at Saturn in 2004 and continues operations to this day. I can only imagine how much he would have loved the images sent back by this mission.

Stray Observations

  • Much of this article and my thoughts about Voyager in general are deeply influenced by Stephen Pyne's excellent book, "Voyager: Exploration, Space, and the Third Great Age of Discovery." It takes an important philosophical view of Voyager and its place in history – a unique approach among books about this mission.
  • I love the scene of Sagan describing the technology at JPL. This being 1980, he had to explain pixels, hard drives, and other basic computing elements we take for granted. Plus, just look at the size of those hard disks! I bet they held hundreds of kilobits!
  • Speaking of old tech, can you hear how loud that computer room was?
  • Sagan's firm and true belief that a great society is defined by its openness to new ideas is spelled out quite plainly here with his description of 17th-century Holland. We have everything to gain by embracing exploration and digesting the new information it forces upon us.
  • I do love how Cosmos shows the unbroken thread between 17th-century Dutch astronomers and modern-day robotic spacecraft. The meaning of all of this is so much greater when seen as a small part of a whole.


  • "The passion to explore is at the heart of being human. This impulse to go, to see, to know, has found expression in every culture."
  • "The more you learn about other worlds, the better you understand our own. We speculate, criticize, argue, calculate, reflect, and wonder. We return again and again to the astonishing data, and slowly we begin to understand."

« Episode 5:
Blues for a Red Planet

Episode 7: The Backbone
of Night »

See other posts from November 2013


Or read more blog entries about: product review, history, fun, Voyager 1 and 2, Neptune, spacecraft, many worlds, Saturn, Uranus, Jupiter


Michel Van Pelt: 11/26/2013 04:48 CST

The flexibility of our brain's software is also proven by the fact that we have been able to adapt to very rapid changes in society. From stone tools to the use of internet, and from small bands of hunter-gatherers to millions living in a single city; dramatic different ways of living that evolution normally would not be able to keep up with. Fortunately our brain has evolved to be amazingly flexible, so that the basic Homo Sapiens design has been able to adapt to all this, and change the world rather than the other way around.

Andrew Planet: 11/26/2013 04:36 CST

I personally reckon what genes we have that lets us increasingly evolve through an extended phenotype of technology are those that facilitate us augmented educational neuroplasticity. An educated human being that is rendered affable thanks to it being taught to be so is mentally another species from its close socially aggressive ancestors despite having the same genes. As primates our species has been until relatively very recently, like chimpanzees socially based on male physical strength dominance using coerced relationships and pillaging as means of reproduction. The minds of every next consecutive generation of humans has become more evolved in complexity thanks to the the usage of technology that gives rise to more knowledge that further evolves that technology and the social means of engineering it. To say that neanderthals died out is going against the latest developments in anthropology. Quite a number, if not most, of well known reputable anthropologists believe we the modern humans all have a small percentage of neanderthal genes. That would mean that, asides from some African populations where no inherited neanderthal genes have been detected, most people alive today have neanderthal genes. Therefore, if we are to believe these findings neanderthals genes contribute to the genetic make-up of most people around today which makes them relatively very successful not having at all died out. So if you truly believe that all neanderthals ''died out'' please state that it is only your opinion as you cannot really evidentially know that as a fact. I myself would love to indulge in the belief that I have neanderthal genes but alas, I have doubts due to an article I read, so prefer the middle ground until it is it utterly proved or disproved.

Torbj??rn Larsson: 11/28/2013 09:24 CST

I think this synthesizing of ideas, while adhering to facts, is what makes a great popularizer of science. The energy of Sagan doesn't hurt either. A bit of old science that jumped out to me is how Sagan claimed the rounding of Enceladus craters were due to melting, because they missed the plumes and its connection to the E ring. The ice that isn't resettled at once will be scooped up another orbit to smooth and freshen the surface. "The neanderthals had no Voyager, no sailing ships, no great feats of exploration. They died out, along with every other humanish species, victims of climate change and competition with homo sapiens." The general idea has merit and it was a good reminder of Pääbo's larger hypotheses. However, I must join the choir here, it was a poor choice. - Earlier and concurrent Homo, H. erectus and Denisovans, expanded more, into Asia and Oceania. - The small population of Neanderthals, as well as Denisovans, has an inordinate amount of successful alleles surviving in modern Homo. It was their culture, correlated with the small populations perhaps, that were unsuccessful. - The new Dmanisi result of spread seems to this layman make all these subspecies the same lineage as per their main graph & statistics. I.e. no splits, H. erectus was (a slightly different) us.

Torbj??rn Larsson: 11/28/2013 09:42 CST

"I think this synthesizing of ideas, while adhering to facts, is what makes great populizers of science." So I guess I should add: good work on the commentary series. It is a worthy tribute of Sagan! @Michel Van Pelt: "the basic Homo Sapiens design has been able to adapt to all this, and change the world rather than the other way around." As paleoanthropologist John Hawks point out, arguably our now large population size doesn't hurt either! Since it increases the efficiency of selection, smaller differences can make a signal (be fixed) out of noise (variance and contingency), we evolve faster than ever. Some of these scientists seem to be able to see more genetic sweeps and those sweeps going to fixation too, but I guess the question is still open. @Andrew Planet: "An educated human being that is rendered affable thanks to it being taught to be so is mentally another species from its close socially aggressive ancestors despite having the same genes. As primates our species has been until relatively very recently, like chimpanzees socially based on male physical strength dominance using coerced relationships and pillaging as means of reproduction." That doesn't seem to be entirely in accord with the empirical evidence. We are the relatively meek ape, as evidenced by our small canines and smaller gender differences. (Bonobos cheat: they use sex as bribe. =D) In fact, arguably canine size may be the only trait that was characteristic of the split from the chimp/bonobo lineage, thus defining hominids. (Again, the recent Dmanisi finds may change this, but I dunno in which direction - if upright posture, sometimes walking, will be added or subtracted now that within-group variation is known.) Chimps are brutal. Humans less so. Then we have recent history, I think Pinker has said something on that but I don't know the details: historical violence levels has abated. Enough resources, i.e. a cultural difference, perhaps.

Dan Cook: 11/30/2013 05:13 CST

@T.Larsson Those Dmanisi fossils really are fascinating. Don't have much to add to the discussion other than the obvious remark about how keeping your mind open to newly acquired evidence remains vital. Casey wrote " In which society would you rather live, one that looks out or one that looks in?" Well, I guess my answer is here.

Casey Dreier: 12/02/2013 01:10 CST

@Andrew & @Torbjörn: I don't think that that a ~5% neanderthal DNA representation in some human genomes implies a thriving neanderthal race. Doesn't that suggest that they were completely subsumed into our genome? There's nothing alive today with a 100% neanderthal genome. We also don't exhibit their most notable physiological characteristics (flared ribcage, small brains,, etc.), again suggesting they are a dead species. Plus, only certain ethnic groups have neanderthal DNA – I believe most humans living in Africa have none. That implies to me that whatever DNA some of us picked up from Neanderthals does not define our most human characteristics – large brains and our urge to explore.

Andrew Planet: 12/04/2013 06:09 CST

@Torbjörn I think you overlook how a dependance in the extended phenotype of technology can make biology vestigial in humans, not that I've read of that anywhere. Our canines are as large as the spear or knife point we choose to make or the nuclear bomb some nation might be pointing in your direction. Rape and pillage has been a documented vehicle for of reproduction for homo sapiens in all populations regardless if they are considered at having some neanderthal ancestry or not. Humans are just as brutal as chimps. I suggest you read the book, Sexual Coercion in Primates and Humans @Casey. Well studied reply. At least you now concede that we might have some neanderthal ancestry through introgression, therefore some of their DNA might still be alive today and so they might have not completely died out. To settle the matter it would be very useful to know what, if any, Neanderthal genes have persisted in the human genome and if so is it because they augmented survival by the traits they imparted. I tend to agree with your argumentation that,''whatever DNA some of us picked up from Neanderthals does not define our most human characteristics,'' but have to strongly disagree with it being the size of the large brain because they are known to have had at least on average, brains equal in size to ours, or even larger.

Torbj??rn Larsson: 12/05/2013 07:12 CST

@Casey: There isn't a one gene-one trait correspondence here. And an important note considering the arguments: neanderthal brains were, as arguably most ancient homos ~ 600 - 200 ka bp, larger than ours. In the neanderthal case it is a statisticically significant difference AFAIK. But I was arguing that 5 % of alleles corresponds to success compared to perhaps 1 interbreeding/generation at the most. @Andrew: You are assuming a steady technology base, which arose ~ 2.5 Ga bp as compared with the hominid split and the small canines ~ 5 Ga bp. Certainly, I will look into the reference. But claiming that humans are as a species as brutal as chimps is an extraordinary claim that would need evidence. How do we establish rape and pillage in ancient populations in the relevant time frame (see my response to Casey)? I have never heard of such evidence.

Andrew Planet: 12/05/2013 08:51 CST

@Torbjörn thanks for your feedback, well worth comtemplating, which I will, if its only to try to fortify my own convictions or change them relative to the earliest developments in tool in humans or other hominoids. The book I mention is a worthwhile read especially if you have the chance to view videos of chimpanzees hunting other primates or murderously attacking in troops butchering others from their own species which as I recommend for a comparison.

Andrew Planet: 12/06/2013 05:53 CST

@Torbjörn Just wanted to reassure you that all is not woe. Although humans are just as brutal as chimps what makes us different to them is that we possess a vastly augmented ability in malleable neuroplasticity. We can override and redirect violently subjective propensities by objective educational inculcation of our mind producing brains. We can in effect reprogram ourselves as biological computers.

Jimi Maze: 12/18/2013 04:33 CST

I do feel we are being human being chauvinist. Life explores. I'm Canadian but I'm in Germany for the holidays. Today I saw both a squirrel and a daddy long legs. Both are quite common in Canada. Their ancestor's must also have a wanderlust. To use James Cook, Cristoforo Colombo, or Hernän Cortez as examples of 'being human' is inaccurate. These explorers are a rare breed. Most human's stay home and want to stay there. Tribe's emigrate because they have to. To find more food, political persecution, changing climate, etc. causes tribes to explore new grounds. As for brutality, I am in Lübeck, Germany and it was bombed flat on Palm Sunday 1943. Both of my grandfather's were Allied bombers. Ack... brutal! I've been strongly thinking about the possibility that thinking that life would spontaneously begin on Earth or Mars may be as primitive a thought as believing a flat Earth centred the Universe. I'm exploring the possbility that it came here much like the Huygens Probe came to Titan. I'm thinking that probes were sent from far away and much different life. Life as a whole is more powerful than humans as a race. There are many many lifeforms big and small that are super brutal. It's how life stays strong to survive. Thanks Casey for the discussion.

Andrew Planet: 01/03/2014 09:12 CST

Forgot to mention another good book for reference, The Dark side of Man, by Michael Ghiglieri

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