The Edge of Forever

(Galaxies, Universes, and Dimensions)
by Carl Sagan
A Personal Voyage
13 episodes
See below for
DVD purchasing options
(Carl Sagan's Cosmos episode no. 10)
  • written by Carl Sagan and Ann Druyan & Steven Soter
  • series director & executive producer Adrian Malone
  • Mt. Wilson and Monterey sequences directed by David F. Oyster
  • India and VLA sequences directed by David Kennard & Oyster
  • Doppler Train sequence directed by Tom Weidlinger
  • edited by James Latham (film) and Roy Stewart (videotape)

  • Main Title Theme by Vangelis
  • Music by Vangelis, Keith Mansfield, Clem Alford, and others...
  • 1 documentary @ 63 minutes

Data Capsule Review

by Martin Izsak

Here we are at another of the good and fascinating episodes of Cosmos. This episode intends to operate at a very large scale indeed, and the opening wastes no time in demonstrating just how BIG the ideas will be.

The hauntingly mythical image of Sagan's silhouetted figure appearing as though out of the afterlife teases us with the idea that our common Human experience of birth may have inspired us to see something similar in the universe at large.

Meanwhile, our Ship of the Imagination shows us exactly what that universe is made of: galaxy after galaxy, in all different sizes, shapes, and various compositions. In addition to many outstanding still photographs, the incredibly slow motions and turbulences within galaxies are also brought to life with some very early computer simulations. This soon extends to consider the trajectories of the galaxies relative to each other... Did we Humans artificially plaster some concept of "birth" on top of this?

In this episode, Cosmos gives us one of its key historical recreations, although it sadly remains a bit confusing. The narration tells us about Edwin Hubble and his assistant Milton Humason, while the visuals consist of two actors, one playing Humason and the other playing his assistant "Mr. Nelson". Additionally, the narration hasn't quite finished describing Humason as a blue-collar labourer and janitor before we see him decked out in a fancy 3-piece suit, driving to the observatory and giving out orders. Without paying careful attention, it's not very obvious who is supposed to be who. A little more clarity in matching narration to visuals might have been ideal here. That said, this does turn out to be one of the most worthwhile recreations Cosmos ever did, particularly in how we get to see the real telescope of the story and all its accessories in action.

Participants include:

Dr. Carl Sagan

Astronomer, host, narrator
Todd Mason
Actor, who plays:

Milton Humason

Co-discoverer of galactic motions
with Edwin Hubble
Galen Thompson
Actor, who plays:

Mr. Nelson

Night Assistant to Humason

Doppler Distanced from the Observer?

The prelude to this recreation is all about the concept of Doppler Shifts, which are introduced by examining the shifting pitch of the sound of a passing locomotive train horn. One way of understanding this, which is perhaps the easiest way, is to think of the speed of an approaching train being added to the speed of the sound on its way to the human ear, and then later, the speed of the receding train being subtracted from the speed of the sound. When that human ear then analyzes the waveform of the sound, it really can't tell the difference between the speed of the sound and its frequency. The ear makes a perfectly natural mistaken assumption - that the speed is just fine, but the frequency has changed, therefore the pitch of the horn is off. We human beings are smart enough though, to think beyond our raw perception and realize when something else might actually be going on.

But new ground was broken in the 1920's when astronomers theorized that the LIGHT from distant galaxies might also be experiencing a Doppler Shift. Notice the date, the 1920's - Einstein's two Theories of Relativity were only just gaining traction in the English-speaking world. To what extent might the phenomenon of Doppler Shifts from the light of the galaxies have been created in a pre-Relativity mindset, and then have had to modify itself to accommodate Einstein's theories? If you think about the two ideas as they are presented here in Cosmos, they really don't seem to fit together very well at all.

Relativity itself was an attempt to allow two contradictory ideas to support each other, one of those being Einstein's interpretation of Maxwell's law of propagation of light. If we express that relevant bit "through the front door", light in a vacuum somehow magically always travels at the speed "c" relative to the observer. To express this same thing "through the back door", as Sagan expressed it in episode 8, thou shalt not add the speed of the source of a light to the speed of the light as it travels. Gee, we can't add velocities for light the same way we did for sound, or so Relativity tells us. Does that not bugger up the entire concept of galactic Doppler Shifts?

As I understand the galactic Doppler Shift example presented here in this episode, there is perhaps one additional assumption which is not being highlighted. And that is that when we look at the light of the distant galaxy and we see two dark lines of some frequencies that are missing from its colour spectrum, we ASSUME that we know what that REALLY is supposed to be. Oh yeah, those lines are the signature of calcium deposits, and they should be over here at this part of the spectrum, but something has red-shifted all the frequencies over to this other part of the spectrum, so understandably, the colours are off here, the same way that the pitch of the train horn was off. But if somehow we are wrong about what these two lines REALLY represent, if they're not due to calcium but something else, it's one more way that the house of cards of our understanding of the universe might come crashing down. Though I might throw up a word of caution there, I don't actually believe this is a bad assumption for us to make at this point.

At any rate, it seems that we can take these "wrong" colours, this frequency shift, and mathematically re-interpret it such that it is the right frequency at the wrong velocity, and from that get an idea of how fast the galaxy may be moving towards us or away from us.

I don't suppose it should matter if light travels to us observers at "c" relative to ourselves, or at "c" relative to the source... in terms of reversing the math to figure out how fast the source is traveling relative to us. But in terms of grasping the concept of what's going on, there is a significant difference. Einstein's Relativity seems poised to remove the possibility that the fundamental misinterpretation of velocity for frequency happens at the eyeball, or telescope, or photographic plate, during perception. Instead, it insists that the "misinterpretation" is happening out at the distant galaxy, at the point of light emission. It reminds me of a classic old ego-flip that science had to correct centuries ago, to go from believing that the universe revolved around us, to the idea that we are spinning regularly within the universe.

How does a galaxy emit its spectrum of light at "c" relative to us with the frequency being just that bit off? Conceptually, it's much easier to grasp a predictable, calculatable misinterpretation in an eye or instrument that assumes light should arrive at speed "c", rather than a galaxy that emits false frequencies at whatever varying speeds are necessary for any observers that may happen to be looking. In other words, it's easier to believe in the Doppler Shift phenomenon for light without Relativity than it is with Relativity.

Incidentally, astronomers seem to have at least two separate ways of calculating galactic red-shift, one based on the math of Newton & Galileo, and a "Relativistic" one based on Einstein. Do we have any reliable way of verifying which one (if either) may really be right? Would the difference between the two make fundamental differences in our interpretation of cosmology as a whole, in how the universe began, how it might end, whether or not its life is cyclical, whether or not dark matter or dark energy are required to make it work?

At any rate, after having demonstrated how we came to believe we know how fast the galaxies are all moving, and in which directions, "Cosmos" makes a quick leap from this evidence to the concept of the Big Bang. Fair enough. In actuality, as might be considered typical in science, the ideas didn't flow along quite so easily and smoothly. Much more depth on that particular part of the story can be found in the 1st season special episode of "The Universe" entitled "Beyond the Big Bang" - a worthwhile eye-opening companion piece to this episode.

Flatland and 4D Space Curves

The next section of the episode retells the classic story of Flatland, while mentioning its original author. Though this is perhaps realized more memorably in extended editions of "What the Bleep Do We Know", Cosmos is unique in using this as a springboard for tackling the more interesting idea of a 4th spatial dimension. Thus we get to see both how a 3D cube can cast a shadow into a 2D world, and how a theoretical 4D cube, or tesseract, can cast a "shadow" into our 3D world - that shadow being realized as a complete 3D sculpture. This is a fascinating idea, but the actual 3D tesseract "shadow" doesn't really seem to be a very convincing representation of what it is supposed to be. The abstract idea itself was easier grasp. Still, it's nice that someone made this attempt.

But... holy cow, check out Wikipedia's page for the Tesseract, because this 3D shadow gets much more convincing when it is put in motion, and the 4D cube rotates before your eyes. Whoa, what are we looking at here? Now THAT will blow your mind!

We then move on to apply this idea to a theoretical curvature in space, which is cool. Sadly the graphics here, as in similar sections in episode 9, are only cartoonish and a bit disappointing. It seems either time or the budget, perhaps both, had run out. Oh well. It still seems to be rather neat in the end anyway.

It's additionally interesting to note how this whole Flatland / 4D / Space Curvature sequence seems to be a reflection of the sequence of similar ideas in Einstein's 1920 book about Relativity, specifically where he avoids math and sticks to conceptual ideas to prepare the reader for the leap from Special Relativity to General Relativity. The big difference there may be the idea that he wants to twist time mathematically until it can be represented as if it were a fourth dimension of space, which apparently has some purely mathematical benefit. Whether or not that process is accurate or valid may remain a separate point entirely. For my tastes, I find that Cosmos episode 10 here has a far cleaner and more tasteful interpretation of the core ideas, where that 4th dimension can be its own spatial thing, and not some twisted re-interpretation of time. Good one!

Mythic Cosmology from India

Our next segment takes us to India, where Sagan explores Hindu culture, customs, and - most significantly - religious myths. In particular, many of these myths reflect modern cosmological thinking, and at the correct timescale of billions of years as well.

I tend to favour the concept supported by both these Hindu myths and the scientific models of a Big Bang followed by a Big Crunch, where the universe eventually draws itself back together through gravity to "destroy itself", or to transform to the next phase, which could well be the next Big Bang creating the next universe. And on and on, in a cycle. Sagan takes his time with this section, pouring over many more fascinating details of the idea from these various sources and disciplines.

Sagan seems to want to resist ideas of God creating the Universe in his presentation, believing he's well debunked it by saying that it implies an infinite regress of creators creating creators, and what came before each of them? I think he's missed something fundamental - the idea of intelligence as a base unit in the fabric of the universe, more fundamental than the tiniest subatomic particle, string, quark, or meson. Is it not primarily because he assumes intelligence had to arise out of random combinations of atoms that he still searches for something unintelligent to exist before intelligence? If the atoms arose out of the intelligence instead, intelligence can remain the beginning, full stop, nothing prior. Me, I don't need to imbue that intelligence with a persona, and an ego, or try to think of it as a "king on high"... those things CAN be said to have arisen out of the atoms. But it is kind of funny to hear how often Sagan interjects the phrase "completely by accident" into whatever he's describing. Really, "by accident" just means that someone hasn't been able to fully see the mechanism for a process yet. He could leave out his "accidents" and have a cleaner presentation, even though it's still quite good anyway.

Finally, we get a few more notes from radio-telescopes and satellite photos, bringing our understanding of the phenomena up to 1992 levels. Of course, there is a lot of talk these days about theories such as "The Big Freeze" and "The Big Rip", which seem to have gained more traction than "The Big Crunch". But when it comes to interpreting the large swath of new information we are just learning how to gather, I'm reminded of what was said in episode 7 about how Huygens attempted to estimate the distance to the star Sirius. His assumption that it was of the same size and composition as our own sun threw his otherwise reasonable calculations way off. Are we doing the same today with Type 1a Supernovas? Or with Cepheid Variables? Or with the notion that we are looking at a calcium spectrographic "fingerprint" in the light from another galaxy, only it's been red-shifted from where we all-knowingly think it really should be? Might this not throw off our own estimates of the sizes, distances, and masses of many of the deep universal objects? How much of this are we really getting correct? I think if Mankind could add to his knowledge database some observations made from within solar systems other than our own, it would trigger a grand and much-needed self-correction of many astronomical ideas, and/or be a critical corroborating step. How far in our future might such research become a practical reality?

In the end, this is a really nice episode. In fact, it would be difficult to really absorb all the grand ideas layered into it in just one go. This is an episode where one can pick out new ideas on multiple viewings, and it is definitely one of the better ones on Cosmos. Excellent!

International Titles:

Deutsch: Unser Kosmos - "Am Saum der Ewigkeit"

Español: Cosmos - "El filo de la eternidad"

Magyar: Kozmosz - "Az Öröklét peremén"

Русский: Космос - "Край вечности"

Français: "Au seuil de l'éternité"

Italiano: "Sull'orlo dell'Eterno"

(You have seen
"On the Edge/Seam of Eternity"
from the series
"Our Cosmos")

The German cutdown version of the series regularly put the episode titles at the end of each episode as well as at the beginning. Above is an example of the first words to scroll upwards for a typical end credit sequence.

Episode 10 was cut in several places to meet the 42-44 minute timing requirement for ZDF broadcast in Germany in the early 1980's. Although the re-enactment of Humason's discovery is still here, subtle editing ensures that he and his assistant never open their mouths to speak. The really big cut was to lose all the material at the flatland desk, while some of the concepts presented there were introduced in the cartoony sequence of Sagan walking on a grid on a sphere back around to his starting point. Surprisingly, footage and description of India's Pongal festival remained. Dialogue at the cottage pond, including effects preceding causes, did not.

The Music - Episode 10

(Anything written in green text represents a name I made up to help keep some music better identified in my own head.)
(Golden yellow backgrounds indicate selections that also appear on Voyager's Golden Record.)
Collectors' Edition 2000 (DVD) Original 1980
Composer/PerformerTitle 2000 Composer/PerformerTitle 1980Notes
VangelisSymphony to the Powers B, Movement Three
also known as "Theme from Cosmos"
Title Music
George CrumbBlack Angels, Movement 3 - Return
Creation Du Monde

2:57 - 11:09
VangelisThe Little Fête
(on top of above cue)
7:27 - 8:16
Blind Willie JohnsonDark Was the Night 11:09 - 11:57
12:56 - 14:19
Isao TomitaPacific 231 (on top of above cue; whistle effect only)13:12 - 13:21
Harry GoldJoy Ride Hoagy Carmichael /
Garnet Clark
Jack Teagarden
Star Dust, on trumpet/cornet ...15:29
Sweetest Melody 15:26...
14:16 - 16:50
Keith NicholsJelly's Blues
(Jazz of the Twenties)
no music18:14 - 19:02
?? Vangelis?

Claude Debussy /
Isao Tomita

?? Vangelis?

??Comet Movement? - Starfield Glitter

The Engulfed Cathedral

??Comet Movement? - "Skyline"

Comet 16
Fud Livingston / Red Nichols

Hoagy Carmichael /
Garnet Clark

Imagination ...20:25

Star Dust, on trumpet/cornet ...22:48

19:01 - 23:03
Alec GouldMasque William WaltonFaçade: Popular Songhumorous waltz
Igor StravinskyPetrushka, tableau 3 of 4,
Waltz: The Ballerina and the Moor
26:29 - 27:44
more Flatland
Graham de WildeLifestreamEdgar FroeseMetropolis30:10 - 32:00
Keith MansfieldSpheresJean-Michel JarreEquinoxe No. 4 of 832:23 - 34:43
VangelisCreation Du MondeSagan lands
back on Earth

East Indian music section from 36:32 - 50:46
Clem Alford
Clem Alford
Clem Alford
Paul Horn in India
Raga Sind Bhiravi
Raga Yaman
??? small snippet of marketplace bkg??
Raga Sind Bhiravi (with extra echo)
Raga Desh (small snippet)
Paul Horn in IndiaRaga Desh 36:32 - 37:40
37:38 - 38:42
38:40 - 38:46
38:45 - 40:50
40:50 - 40:57
?????? unknown - Indian marketplace live?? ...1980 = 200040:49 - 41:26
T. Viswanathan (flute)Ragam-Tanam-Pallavi in Raga Sankarabharanam - Part 2 of 7: Tanam (end) (fast woodwind) 1980 = 200041:25 - 41:44
Naresh Sohal
Clem Alford

George Fenton
& John Leach
Evening Prayer 41:44 - 43:52
Raga Sind Bhiravi (with extra echo,
on top of Evening Prayer 41:56 - 42:45)
Lands of Beauty 43:47 - 44:51
T. Viswanathan
(flute, vocals)
K.S. Narayanaswami (veena)
Raga Sankarabharanam -
Part 3 of 7: Pallavi ... 42:14
Emi Jesite
(veena jam session)
42:17 - 44:26
41:44 - 44:51
Keshav Sathe

Clem Alford

Tabla Solo 44:51 - 45:27

Raga Sind Bhiravi 45:20 - 48:35

Paul Horn in India

K.S. Narayanaswami (veena)
Raga Vibhas 44:51 - 46:40

Emi Jesite
(warbly veena, jam'n)
Keshav SatheTabla Solo T. Ranganathan (drum)Raga Sankarabharanam -
Part 7 of 7: Tani Avartanam
(mrdangam [drum] solo)
50:31 - 50:46
East Indian music section ends at 50:46

?? Vangelis???Comet Movement? - Data Drilldown
(faint echo at 50:40)
VangelisTheme from Cosmos50:44 - 51:58
SchoenbergTransfigured Nights - Movement 4 of 5 - Adagio52:11 - 54:33
HeldonPerspective II
(on top of above cue)
53:13 - 53:57
VangelisTheme from Cosmos55:07 warm up
to credits
Wm. Jeffery BoydstunIn Motion Delta 01 -> 02n/aCosmos Update
Wm. Jeffery BoydstunMetamorphosisn/aafter bubbles
VangelisTheme from Cosmosend credits
VangelisComet 16n/a2000 Credits

Keith Mansfield
KPM 1000 Series:
All in the Mind

mp3 Album
featuring the track: Spheres



The track Spheres (version A) can be heard
here in Cosmos episode 10.

The track Planet Earth (version D) can be heard in
the 1986 version of "Cosmos: a special edition",
in episode 1: Other Worlds, part 1

KPM 1000 Series: All in the Mind
Keith Mansfield
This album available as MP3 downloads.

Track Listing:

1. Planet Earth (A) (2:07)
2. Planet Earth (B) (0:23)
3. Planet Earth (C) (0:16)
4. Planet Earth (D) (2:05)
5. Planet Earth (E) (0:36)
6. Planet Earth (F) (0:52)
7. Spheres (A) (2:34)
8. Spheres (B) (2:17)
9. Spheres (C) (2:05)
10. Blue Planet (2:00)
11. Celestial Fanfare (1:01)
12. Solar Tides (1:27)
13. Dreams of Future Past (A) (1:29)
14. Dreams of Future Past (B) (1:19)
15. Shadows of Doubt (A) (1:12)
16. Shadows of Doubt (B) (0:55)
17. Shadows of Doubt (C) (0:49)
18. Shadows of Doubt (D) (1:01)
19. All in the Mind (2:07)
20. Don't Look Now (1:14)
21. One Step Beyond (1:19)
22. Fantasy (by Richard Harvey) (3:29)
23. Daydreaming (by Richard Harvey) (1:46)

KPM 1000 Series:
Middle East Suite / India

Library music
by Ali Isfahan, Clem Alford, Keshav Sathe,
and Georges Behar

digital downloads



KPM 1000 Series:
Middle East Suite / India
This album available as MP3 downloads.

Track Listing:

1. Ceremony in Tehran (by Ali Isfahan) (1:02)
2. In Bandar Abbas (by Ali Isfahan) (2:21)
3. Basra Market (by Ali Isfahan) (0:55)
4. Caspian Sea (by Ali Isfahan) (1:46)
5. Haifa Lament (by Ali Isfahan) (2:12)
6. Ankara Streets (by Ali Isfahan) (1:27)
7. Qanun Solo (by Ali Isfahan) (1:12)
8. Baghdad Nights (by Ali Isfahan) (2:17)
9. Arab Oud (by Ali Isfahan) (1:49)
10. Two Turkish Folk Songs (1. Fast) (by Georges Behar) (1:22)
11. Two Turkish Folk Songs (2. Slow) (by Georges Behar) (1:15)
12. Raga Yaman (by Clem Alford) (4:06)
13. Raga Bihag (by Clem Alford) (3:22)
14. Raga Sind Bhiravi (by Clem Alford) (5:24)
15. Raga Bhupali (by Clem Alford) (6:52)
16. Tabla Solo (by Keshav Sathe) (2:04)

Tracks in Bold can be heard in Cosmos episode 10.
Raga Sind Bhiravi can also be heard in episode 9.

This documentary has become available on DVD.
Cosmos - by Carl Sagan: A Personal Voyage

13 hour-long episodes, 1980



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Read the data capsule review for the next episode: "The Persistence of Memory"

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