Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty

Casey Profile Picture Thumbnail

Cosmos with Cosmos Episode 5: Blues for a Red Planet

Where Mars stubbornly refuses to be what we desire

Posted by Casey Dreier

12-11-2013 2:24 CST

Topics: product review, history, fun, NASA Mars missions before 1996, Mars, Curiosity (Mars Science Laboratory)

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 4:
Heaven & Hell

Episode 6: Travellers' Tales »

I hope there's no life on Mars today.

If we were to find life frittering about on the martian surface, humanity would (should?) reach the inevitable moral decision to cordon off the planet from further exploration – it would be irresponsible to alter the evolutionary progress of this other form of life. (What if robotic spacecraft had landed on Earth three billion years ago with a few hungry microbial hangers-on?) In the face of this unique form of life, Mars would become a vast, protected wilderness. Humans, hosts to a pantheon of bacterial communities, would be forever forbidden from setting foot on the Red Planet.

But we need Mars as an offsite backup for humanity. So my hope is that today's Mars is a barren world, ripe for future exploration and (eventually) permanent habitation. Ideally, we'd find evidence of past life on Mars, stimulating scientific research and philosophical revelation, and then we'd continue the search for life in the watery depths on the moons of outer planets. Humans could never settle on Europa or Enceladus, so let life exist there instead.

But Mars excels at denying us our most fervent wishes. From not fitting into the epicycles of Ptolemy, to lacking the canals of Lowell, to supplying no organic materials (yet) to the Curiosity rover team, the reality of Mars has consistently irritated humanity throughout history.

In Cosmos's fifth episode, Blues for a Red Planet, Sagan highlights the ways in which the Mars that is subverts the Mars we wish it to be. In this sense it's a thematic sequel to Episode 3's Harmony of the Worlds, where Mars kickstarted the development of astronomy as a science through the ceaseless taunting of Johannes Kepler to unlock the secrets of its motion across the sky.

This episode also portrays what is clearly a personal passion of Sagan's. Influenced from early childhood by the fantastic stories of Edgar Rice Burroughs, Sagan loved Mars. He deeply wished to discover life there, but Mars denied him the satisfaction of doing so, while keeping just enough hope alive by hinting at a past of liquid water and habitability.

It is perhaps this personal passion for the Red Planet that causes the episode to suffer as an hour of television. I find it the weakest episode in the series so far, lacking in forward momentum, storytelling, and the general clever "interconnectedness" that is so nicely brought to life in previous shows.

The opening sequence featuring a reading of H.G. Wells's War of the Worlds over a bucolic scene of 19th century-life is both predictable and overlong, as if they needed to fill time to reach their hour-long episode mark. I would have preferred a deeper exploration of relationship of the invasion-fantasy to the growing influence of the German empire in pre-World War I Britain and how this subverted the growing confidence of humanity's control over their destiny during the late industrial period. The martians here were defeated not by anything humans could create, but by the very diseases that had haunted our species for millions of years.

The malevolent martians of Wells's imagination evolved, for the most part, into the dying remnants of a once-thriving race as inspired by Percival Lowell's canals. In this vision, the canals are seen as a desperate engineering works project to combat global climate change. This leads to some of the most dated visual effects sequences in the series, as we fly over a artististic rendering of the ancient martian cities to the throws of Holst's Mars.

Lowell, of course, is famous for a theory that turned out to be completely wrong. The canals on Mars – mapped in detailed fashion over many years of hard work – were the projections of his dreams onto the blurry globe of this distant planet. There were no canals and no dying race of martians. Mars once again denied humanity its satisfaction.

Lowell's idea, despite being wrong, was was deeply romantic and filled with dramatic pathos. From the John Carter series to my personal childhood martian influence, Bradbury's Martian Chronicles, the story of the dying race persisted. And though most people understood that it was fantasy, the artistic concept Mars nestled itself deep into our psyche.

The latter half of the episode improves as we move focus to the actual exploration of Mars. Sagan appropriately devotes a good third of the show to the Viking landers – the most ambitious and expensive planetary exploration mission to date (there's a good argument to be made that this is still the case).

Meeting Jake Matijevic, Curiosity sol 43

NASA / JPL / MSSS / Damia Bouic

Curiosity in Gale Crater

Tracks lead off into the horizon made by a roving machine on the surface of the red planet. NASA's Curiosity rover is the manifestation of true martian exploration that Sagan only dreamed of.

Once again, Mars worked to deny the expectations of humanity. Though both Vikings had clever experiments to search for life, they produced, at best, ambiguous results. Instead of clearly providing a "yes" or a "no" to the answer: is there life on Mars today? Mars told us probably not... but maybe.

Since Cosmos was made in 1980, Sagan had no way of knowing that the Vikings would be the last successful mission to Mars for nearly 20 years. The 80s saw deep budget cuts for NASA that targeted the planetary exploration program. Despite the hints of past water and the tantalizing science returned to us by Viking, humanity saw fit to take its sweet time.

That all began to change in 1996 with the launches of both Pathfinder and the Mars Global Surveyor. These missions kicked off a sustained commitment to the exploration of Mars. We've seen a fleet of spacecraft explore Mars in the past twenty years, culminating with the Curiosity rover, far beefier and more impressive than any concept rover portrayed in Cosmos. It's a wonderful coda to this episode. Millions of people are following the exploration of the Red Planet, and not via their television screens, but in the palm of their hand. We are able to trek across the plains of Mars, and though the planet remains characteristically complex and resistant to our inquiries, we are slowly uncovering the Mars that is: a world that was once wet and habitable, but now hopefully dead, patiently waiting for new life to arrive.

Stray Observations

  • Bruce Murray, one of the co-founders of the Planetary Society with Carl Sagan and Lou Friedman, was very much a martian-life skeptic. He and Sagan clashed publicly for years prior to their friendship which led to the formation of the Society. Here's a quote from Murray in 1971, singing the blues for the red planet: "I really don't think there is any life on Mars. There never has been any evidence of it. It has just been a very attractive idea. You cannot completely disprove life on the moon…It just becomes less and less likely. And it has become very less likely as we have gotten more information about Mars. When you go back to find out why people thought there might be life there, it was in part, if not entirely, the result of this wishful thinking and the Edgar Rice Burroughs kind of popularization."

  • The pathos of the dying martian civilization is exemplified in one of my favorite Bradbury short stories from the Martian Chronicles, Night Meeting, where a human and a martian cross paths in time. The martian sees his world as it was: bright and full of life, while the human sees it as it is: dry and dead. It's haunting.

  • I don't have much to say about the Goddard sequence, but it did give me chills when it cut from the video of his small rocket tests to that Saturn V launch.

  • I found it interesting that Sagan didn't mention human exploration of Mars at all in the original version of this episode, and only very briefly during the Cosmos "Update" sequence filmed in 1990. That was right around the ill-fated proposal by the first President Bush to send humans to Mars.

Science Update

  • So much has happened in Mars science since the airing of this episode that it makes no sense to even try and address it all. We've had nine subsequent successful missions that have mapped Mars in unbelievable detail and probed its geologic history. We know that Mars was once habitable to life as we know it, but it's a pretty harsh place now.

  • The outcomes of the Viking biological experiments can be explained by purely chemical processes, as outlined in this summary on Malin Space Science Systems' website (they made the cameras on the Curiosity rover). The oxidizer that they mention in the summary is likely to be perchlorate, first detected by the Phoenix lander, which destroys any organic compounds when heated.

  • The "Pyramids of Elysium" are most likely ventifacts – shapes made from wind blowing in the same direction for eons. This hasn't stopped a thriving cottage industry of fantastical speculation.


  • "I'm a carbon chauvinist, I freely admit it."

  • On a Mars rover: "It could drive to its own horizon every day, a distant feature it barely resolves at sunrise it can be sniffing and tasting by nightfall. Billions of people could watch the unfolding adventure on their television sets as the rover explores the ancient river bottoms or cautiously approaches the enigmatic pyramids of Elysium. A new age of discovery would have begun."

  • "Science is a collaborative enterprise spanning the generations. When it permits us to see the far side of some new horizon, we remember those who prepared the way, seeing for them also."

« Episode 4:
Heaven & Hell

Episode 6: Travellers' Tales »

See other posts from November 2013


Or read more blog entries about: product review, history, fun, NASA Mars missions before 1996, Mars, Curiosity (Mars Science Laboratory)


Denis: 11/12/2013 08:12 CST

> If we were to find life frittering about on the martian surface, humanity would (should?) reach the inevitable moral decision to cordon off the planet from further exploration – it would be irresponsible to alter the evolutionary progress of this other form of life. Imagine that: some people (such as me) disagree with you on this. Microbes are not people and have no rights - otherwise we must stop brushing our teeth every morning, we are committing genocide. Ridiculous isn't it? Your suggestion to ban Mars landings, not for 10-50 years until we fully charactarize Mars life, but *forever and ever*, is about as logical as my suggestion about teeth brushing.

Jimi Maze: 11/12/2013 08:55 CST

2/3's of The HG Wells segment could have been replaced by more Goddard sequence, true. I too cannot see "Life On Mars" being reason to stop visiting. What would Columbus do (I'm being cynical here) ? I've got Bowie "Life on Mars" looping through my head. I am exciting for the NdGT Cosmos to clearly lay out the culmination (is that the right word?) of our current knowledge of Mars. Personally, I need more proof that Mars USED to be habitable. The stuff of life. I love when he stirs the potion. How much ARE our elements worth on today's market? $5? Vishniac sequence almost seems whiny. I live in Toronto, so a common summer's day on Mars is what we call late January. I might want to watch Schwarzenegger's Total Recall this week. I do believe his mission was to melt the icecaps and reoxygenize (probably not a word) Mars ya? I cannot, for the life of me, think of an economic reason to go to Mars. Perhaps to mine it? But what is worth rocketing back to trade with Earth? Hmm. Perhaps tourism? All this has me thinking; how do we exit a planet without using fossil fuels? A trillion yes answers to that. You can read my live-tweets @jimimaze

Daniel Ruplinger: 11/12/2013 11:18 CST

We all know what it's going to take to get a definitive answer on "Life on Mars?" Human beings exploring every Martian cavern they can find. Sounds like a great adventure.

Casey Dreier: 11/12/2013 11:39 CST

@Denis: The important part isn't that they're microbes, but that they would represent a unique and unknown biology on its own evolutionary track. How would humans and their bacteria disrupt that biology? It's hard to say. Maybe we wouldn't, at which point my worries would be moot, but it's difficult to predict with 100% accuracy. Again, to go back to my analogy, 3 billion years ago our archaean ancestors were floating about in the Earth's oceans. They were just microbes and didn't even have anything as advanced as a cell nucleus. If a foreign species had swooped in and dominated the biosphere, would we have evolved as we did? Most likely not. That's where my deep moral reservations come about. We don't know what's going to happen on Mars 3 billion years from now. Maybe nothing, but is it our right to decide the fate of an alien biology? Or even to risk it?

Casey Dreier: 11/12/2013 11:41 CST

Daniel: Yes, despite my reservations that may be the only concept able to kick up the investment in order to send humans to Mars.

Casey Dreier: 11/12/2013 11:45 CST

@Jimi: Economic reasons for humans on Mars? I can't think of any either. My personal feeling is that Mars represents an accessible backup storage for humanity in case of a global catastrophe, but that's not an easy sell. The new Cosmos will almost certainly feature Mars in a big way (how could it not?) and I did spy a quick clip within its trailer of the SotI flying past what looked to be the Viking 1 landing site. As to habitability, for me the big selling point was the evidence of a body of neutral-pH standing water that Curiosity found (via drilling into mudstones in Gale Crater). That sounds pretty habitable! And I like the Total Recall idea. Maybe we should do a #CosmosWithTotalRecall at some point...

Torbj??rn Larsson: 11/12/2013 02:15 CST

This episode was a bit light on the astrobiology, except Sagan's water & carbon chauvinism tying it together with earlier episodes. But maybe we are looking at it from a vantage point of so much more Mars data, especially imagery. I've never seen Viking's experiments as clever, in that they would, and indeed got, ambigious results from soil chemistry alone which needed much later follow up missions to resolve. Granted that research is step wise, but that particular conundrum was predictable. Sagan's description how another, more biologically observable, experiment was dropped for budget reasons may be the answer. I too cannot see how we have a moral responsibility to another biosphere. We have just started to broaden our morality from own species to some of those we harbour (and eat), but it is premature to speak of biosphere morality. Practically we have to get there to find out. And we can't "cordon off" Mars, in the same way that ~ 200 kg/y of Mars drops down on Earth we export life there yearly. Even if we would develop technology to stop further hyper velocity impactors, the existing "tram line" would continue for eons. I don't think non-adapted terran species would impact Mars any more than martian species has impacted us through deep time, given that they were or are still inhabiting crustal refugia. OTOH if they did, a mixed biosphere may be a great experiment. Re Mars as a current backup, that _is_ a hard sell, seeing how Earth has survived 4 billion years. But given that terraforming would make Mars habitable for a billion year or so, it may be a future habitat as the Sun heats up.

stone: 11/13/2013 03:50 CST

The interpretation of the Viking biological experiments is much more complicated than outlined in the Malin summary. Why is Malin quoted to interpret the data? This like asking Nikon to give a explanation for the static calculations of the Eifel tower because Nikon cameras are used in Paris. The mentioned perchlorates are no oxidizers in the temperature range used in the experiments. They are not the cause of the observed labled release. The peroxides postulated for a long time are not present in the amount needed and other strong oxidizers are most likely not present because their is a good amount of iron(II) present which would undergo oxidation. Without the GC-MS data, and the GC-MS was not part of the Viking biological experiment the Viking biological experiment showed positive results for metabolism. With a devastating malfunction in the GC-MS at the beginning of the mission there would be a strong case for life on Mars. The GC-MS worked flaw less with a precision and accuracy still hard to archive decades later. The case is not yet that clear. I do not think that there was life in the samples of Viking, but this is based on a lot of other things not only the Viking results. A soil oxidation potential experiment would be nice and would settle the discussion on the not fully understood results.

Denis: 11/13/2013 10:20 CST

> Again, to go back to my analogy, 3 billion years ago our archaean ancestors were floating about in the Earth's oceans. They were just microbes and didn't even have anything as advanced as a cell nucleus. If a foreign species had swooped in and dominated the biosphere, would we have evolved as we did? Most likely not. Yes. > That's where my deep moral reservations come about. We don't know what's going to happen on Mars 3 billion years from now. Maybe nothing, but is it our right to decide the fate of an alien biology? Yes. We are perfectly allowed to affect "the fate of an alien biology". We are affecting a lot of things by merely living. Logically speking, if you are concerned about "affecting things", you should be wanting to kill yourself, right? Other points: "Affecting" things is very far from "damaging" them. Waiting some billion years to see what would happen on Mars is not practical in the extreme. There are several billion Mars-like planets in this Galaxy alone. It can't be something unique that we must forgo exploring and colonizing it. How do you imagine someone can prove that Mars has no life? Maybe it's only deep subsurface. What's your plan for that - ban Mars landings forever as a precaution, since "Mars may have life, we just don't know it". If you are logical, this should be your position.

Dan Cook: 11/13/2013 08:04 CST

Imagine that: Zubrinites, right on time. Re: Planetary Protection It won't matter anyway. If there's money to be made either from developing proof of concept launch technologies or from good old fashioned real estate deals, no amount of ethical consideration will prevent the exploitation of Mars. There is no precedent for anything else. We will go. Re: Other financial considerations or motivations for that first mission. It's not the tangible profits that one should consider but all of the ancillary benefits. A Mars landing would inspire a whole new generation of young people to come up with new technologies that could benefit everyone.

Torbj??rn Larsson: 11/28/2013 12:02 CST

@stone: Malin's summary is simple enough. They can exclude biological processes from wet chemistry, not heat as you claim. And to repeat that the document says, that makes the Labeled Release ambigious so non-conclusive. As Sagan says, extraordinary claims need extraordinary evidence. An exclusion from several tests and combined with some data that must be rejected as ambiguous is safely described as not the asked for extraordinary passing of tests. Is the case clear? Sufficiently to have had a strong consensus, I take it. Is the case closed, is perhaps the more relevant question. Yes, Curiosity did that, no organics.

Jimi Maze: 12/18/2013 03:29 CST

I feel no moral worry about occupying Mars even if there are microbes. Seems natural enough to me.

Leave a Comment:

You must be logged in to submit a comment. Log in now.
Facebook Twitter Email RSS AddThis

Blog Search

Planetary Defense

An asteroid or comet headed for Earth is the only large-scale natural disaster we can prevent. Working together to fund our Shoemaker NEO Grants for astronomers, we can help save the world.


Featured Images

SpaceX CRS-8 landed booster
SES-10 static test fire
More Images

Featured Video

Class 9: Saturn, Uranus, and Neptune

Watch Now

Space in Images

Pretty pictures and
awe-inspiring science.

See More

Join The Planetary Society

Let’s explore the cosmos together!

Become a Member

Connect With Us

Facebook, Twitter, YouTube and more…
Continue the conversation with our online community!