Thursday, August 27, 2009

Tripping the Light Fantastic – Connecting Now and Then, Here and There

In which the blogger begins and ends with Moby (a “Moby” strip, if you will); finds (without necessarily shedding light on) an illuminating way to connect paleontology and astronomy, time and distance; retreats in the face of various conundrums; and says that fossil collecting is life affirming (talk about muddled thinking).

I've seen so much in so many places
So many heartaches, so many faces
So many dirty things
You couldn't even believe.

~ Moby, Extreme Ways

For someone who has never seen any of the Bourne movies (Identity, Supremacy, and Ultimatum), the meaning of Moby’s song Extreme Ways (appearing on his album 18) may be up for grabs. But the song is used in the closing credits of all three movies, so, for a Bourne fan (like me), the song and the Bourne experience are now inextricably linked. Moby’s lyrics have no meaning outside the context of the films. It’s a connection that, once made, is impossible to sever.

Similarly, in a deceptively simple essay, amateur astronomer and telescope maker Randall Wehler makes a fascinating connection between paleontology and astronomy, one that for me is now wholly visceral and irreversible. This posting is about Wehler’s special connection and a little coda I just stumbled on. (This all may well be humdrum, but it wasn’t for me.)


In an essay entitled Two Journeys Back in Time, Wehler describes the summer ritual he and his brother follow (Sky & Telescope magazine, December 7, 2007). Each year, they journey to Wyoming and spend a week on a cattle ranch working through rock from the Lance Formation in pursuit of fossils from the Cretaceous Period. One summer, Wehler brought along a telescope and binoculars and the brothers spent their nights scanning the skies, looking at faint objects in the brilliantly clear Wyoming night skies. It was at that juncture that Wehler has his epiphany.

As he writes,

. . . it was a deep, awakening feeling of connectedness not only with our Earth, but with realms far beyond our Milky Way as well.

The fossils that we held in our hands were 65 to 70 million years old. For galaxies about 65 to 70 million light-years distant - just beyond the Virgo Cluster, for example - the light we saw that night started for Earth when these creatures were still alive! For an instant, time seemed to become the obverse of space, and vice versa, as we pondered the vastness of both these dimensions blending in some ineffable way.

It was a serendipitous discovery and realization whereby both of my hobbies - astronomy and paleontology - became similar journeys back in time and converged. I found these thoughts in some way reassuring, and the emotional part of me sensed peace.

That realization was new to me just as it was to Wehler. In traveling that distance from beyond the Milky Way, the starlight creates a bridge across an expanse of space and a gulf of time. These are very real connections.

Light Conundrums

The more I thought about it, the more I realized that Wehler’s starlight raises some serious scientific and mental hurdles, and my repeated efforts to compose this posting convinced me that I cannot get over them. I will, nevertheless, suggest some of their aspects that intrigue (and befuddle) me.

To astronomers, a light year, as in “65 to 70 million light years,” is a measure of distance, not time. It’s sloppy thinking to treat it as a gauge of time. A light year is a way to speak of astronomical distances conveniently; otherwise, we’d have to deal with huge numbers if we chose to speak of, say, miles or kilometers.

Still, in many minds (like mine), distance and time do come together. Interestingly, on this point I turn to physicists, not astronomers. As Joel R. Primack and Nancy Ellen Abrams (the former a physicist, the latter a philosopher of science) write in The View from the Center of the Universe: Discovering Our Extraordinary Place In The Cosmos (2006),

When we look out into space, we look back in time. . . . Because of the fixed speed of light and the ongoing expansion of the universe, the size of our visible universe, which is a spatial quantity, is always changing depending on what we can see, which depends on time - specifically, the age of the universe. In modern cosmology space and time are more than intimate; they’re inextricable. (Emphasis in the original, p. 122-123.)

That observers of the light and emitters of the light are in motion relative to one another leads to some serious weirdness entering into the equation. Physicist Brian Greene treats the starlight phenomenon in terms that Wehler might relate to, at first. He writes of light leaving, say, the Coma cluster, some 300 million light years away, so when we look at that cluster we see it as it was then. But, when he considers that the Milky Way and the Coma cluster are in motion, he introduces special relativity into his discussion. At that juncture, things fog up for me very quickly. The nows on Earth and in the Coma cluster are not the same. I cannot pretend to understand the concepts involved, but I get a passing glimpse of the consequences of special relativity in one of Greene’s conclusions:

Observers moving relative to each other have different conceptions of what exists at a given moment, and hence they have different conceptions of reality. (The Fabric of the Cosmos: Space, Time, and the Texture of Reality, (2004). In the original, this sentence is italicized, p. 133-134.)

Clearly, space time bridges behave in strange ways.

Yes, this is the coward’s way out (and a sign of intellectual laziness), but I think it best to just leave Wehler’s insight about starlight at its simplest and skip the complications that are inherent in it. We are seeing light that was first emitted at the time the fossils were parts of living beings. This light links us to the fossils and to the vast reaches of the universe. Enough said.

Well, perhaps there’s a bit more that should be added to this – a little Badlands coda on seeing this ancient light.

An Incident in the Badlands

Loren Eiseley, anthropologist and writer, in his essay The Judgment of Birds (from The Immense Journey, 1957) describes an incident at the end of an autumn day spent collecting fossils in the Badlands. He recounts his growing uneasiness as the sunlight fades and he recognizes that he has to return to camp before night falls, otherwise he’ll be left stranded in the dark. He climbs a hill to orient himself in this stark dry land, this “dead planet” as he calls it.

He writes, "Fifty million years lay under my feet, fifty million years of bellowing monsters moving in a green world now gone so utterly that its very light was travelling on the farther edge of space.” Those beasts were long extinct, leaving this land with “silences as deep as those in the moon’s airless chasms."

It was then that a flock of migrating warblers sweeps across the darkening sky heading south and directly toward him.

Alone on a dead planet I watched that incredible miracle speeding past. It ran by some true compass over field and waste land. It cried its individual ecstasies into the air until the gullies rang. It swerved like a single body, it knew itself and, lonely, it bunched close in the racing darkness, its individual entities feeling about them the rising night. And so, crying to each other their identity, they passed away out of my view.

To Eiseley, that racing flock of birds is an affirmation of life in the face of the dead land, in the face of the dead and buried and fossilized beasts of fifty million years ago, and in the face of the coming night.

But, I think Eiseley paints the contrasts between the life (here and now) and death (there and then) too starkly, perhaps just for the sake of his essay. His very collecting of bones from the vanished creatures is life affirming, it’s an act to build an understanding of that past world. And, though that world is buried and parts of it fossilized, it still lives in Eiseley’s mind. How else to explain his vivid imagery of that world – “bellowing monsters” in a world where “dark, savage brains had roamed and roared their challenges into the steaming night.” These pieces of stone revive their world, if only in our minds, and offer the solace that life is robustly persistent, if not consistent.

Eiseley’s description of that fifty million year old world contains a marvelous postscript to Wehler’s insight on ancient starlight. As already quoted, Eiseley writes of “a green world now gone so utterly that its very light was travelling on the farther edge of space.”

There’s the new insight (it’s surely another commonplace observation – I just never really thought about it before) – the starlight flows both ways. [Later edit: Yeah, I'd thought of it before, just not in the specific context of Wehler's connection. That's what was new for me. Ah, still muddled, I guess.] Earth is the source of ancient light, light that emanated from our star and reflected off our planet long ago. Though Eiseley wants us to treat that light as an image of desolation and death, passing through dark empty space far beyond our ken, his imagery speaks to me of life. Not just that there was life here at the moment this light was first reflected. No, I also sense that our light is out there to be seen. And, since it takes two to tango (or trip the light fantastic), I’m favoring there being sentient beings on both sides of these space and time bridges peering across the distance into the past.

Completing the Loop – Where Did I End Up Anyway?

To complete the “Moby” strip, I’ll close with another song in which Moby describes a more fundamental and physically very real stellar connection (whether or not this is what he meant when he composed it):

People they come together,
People they fall apart,
No one can stop us now
‘cause we are all made of stars.

~Moby, We Are All Made of Stars

Notes on Sources

~ The Judgment of Birds, from Eiseley's 1957 book The Immense Journey is reprinted on p. 525-533 of The Norton Book of Nature Writing, edited by Robert Finch and John Elder (1990).

~ A copy of Wehler’s article might be found on the web, but there’s nothing official from the magazine as far as I can tell.

~ Greene also writes of the two way flow of starlight. In The Fabric of the Cosmos, he hypothesizes an astronomer today in the Coma cluster using a powerful telescope to see what is (was) going on on Earth. The light she’s viewing, of course, left our solar system 300 million years ago. So, says Greene, her view may well be of Paleozoic ferns and arthropods.

Picture Credits

~ Picture of the M81 galaxy group (part of the Virgo cluster) is from NASA at this site.
~ Coma cluster picture is from NASA at this site.
~ Badlands picture is from the National Park Service at this site.
~ The amazing trilobite picture is of a Walliserops trifurcatus from the Devonian, roughly 370 million years ago. Picture is from the Smithsonian Institution at this site.

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