Extraterrestrial Worldview

Earth orbits the Sun at sixty-six thousand miles per hour needing 365¼ days to notch a round trip.

The conceptual model of Earth's extraterrestrial relationship to the cosmos has changed since antiquity. Natural scientists and philosophers have put forth three paradigms:

1. The Sun, Moon, stars & naked-eye planets circle the Earth;
2. The Earth & planets circle the Sun; and
3. The Earth & planets orbit the Sun in an elliptical path.

Period	Model	Belief	References
350 BCE to 1500	Geocentric	The astronomical system of many civilizations, including ancient Greece, held that the Sun, Moon, stars, and planets circled Earth.	Aristotle's cosmological treatise On the Heavens, recorded in 350 BC, and Claudius Ptolemy's astronomical treatise Almagest, recorded in 150 AD, consider a stationary Earth as center of the universe.
16th C	Heliocentric	The Copernican Revolution held that Earth and planets follow circular orbits around the Sun.	Nicolaus Copernicus published On the Revolutions of the Heavenly Spheres in 1543. Copernicus provided the seminal work of Renaissance astronomy that describes the paradigm-shifting heliocentric model.
17th C	Elliptic orbits	Earth, a small body, orbits the Sun, a large body following an elliptical path, with the Sun located at one of the foci of an ellipse.	Johannes Kepler improved on Copernicus's heliocentric theory. Kepler's first law of planetary motion (published between 1609 and 1619) describes the elliptical path of planets traveling at variable speeds around the Sun.

American philosopher John Dewey wrote of the Copernican Revolution:

Knowledge falters when imagination clips its wings or fears to use them. Every great advance in science has issued from a new audacity of imagination.
— John Dewey

Heliocentric
Mars & Earth circling Sun

Geocentric
Mars & Sun orbiting Earth

Kepler's elliptical orbit is our current conceptual model. Planets orbit the Sun on an elliptical path with the Sun located at one foci of the ellipse.

The Sun shown as the foci of the elliptical orbit of a planet.

Reflecting on Copernicus's paradigm-shattering hypothesis in The Quest for Certainty, John Dewey cautions us against inflexible beliefs and urges us to beware obstructions to advancing our worldview.

It has to search out and disclose the obstructions; to criticize the habits of mind which stand in the way; to focus reflection upon needs congruous to present life; to interpret the conclusions of science with respect to their consequences for our beliefs about purposes and values in all phases of life.
— John Dewey

REFERENCES

• Copernican Revolution, Wikipedia.
• Heliocentrism, Wikipedia.
• The Quest for Certainty: A Study of the Relation of Knowledge and Action, John Dewey, Gifford Lectures 1929. London.
• Ptolemaic system, Britannica.

Stone Sermons

Of the jagged horizon south of the Tuolumne Meadows, John Muir's journal entry regarding Cathedral Peak reads:

It is a majestic temple of one stone, hewn from the living rock, and adorned with spires and pinnacles in regular cathedral style. The dwarf pines on the roof look like mosses. I hope some time to climb to it to say my prayers and hear the stone sermons.

Muir's journal entry on page 266 of My First Summer in the Sierra and Selected Essays was written in 1869 as Muir approached the middle age of 31 years.

The Cathedral Range. Cathedral Peak is the houndstooth spire on the right.

Muir mused about returning to Cathedral Peak to climb the temple of one stone and to hear the stone sermons.

Whether physical or imagined, our trek requires resilience of body and mind. Because we have limited capacity for minutia, we condense our experiences into tightly edited vignettes that, strung together, form a narrative that becomes our handhold to a semblance of Self.

In the poem Releasing the Sherpas, Campbell McGrath considers body and intellect as the sturdy but perhaps expendable porters carrying our freight through steep spires of glacial ice.

Releasing the Sherpas
by Campbell McGrath

The last two sherpas were the strongest,
faithful companions, their faces wind-peeled,
streaked with soot and glacier-light on the snowfield
below the summit where we stopped to rest.

The first was my body, snug in its cap of lynx-
fur, smelling of yak butter and fine mineral dirt,
agile, impetuous, broad-shouldered,
alive to the frozen bite of oxygen in the larynx.

The second was my intellect, dour and thirsty,
furrowing its fox-like brow, my calculating brain
searching for some cairn or chasm to explain
my decision to send them back without me.

Looking down from the next, ax-cleft serac
I saw them turn and dwindle and felt unafraid.
Blind as a diamond, sun-pure and rarefied,
whatever I was then, there was no turning back.

Nearly frostbitten, clinging to an ax-cleft serac, our body and intellect need coaxing. Our intellect, buttressed by unimaginable fortitude and resilience, summon physical strength.

We walk over wind-blown passes to descend into verdant valleys. We move on to face an undeterminable number of sunrises and sunsets.

There's no turning back.

Far up the Pilot Peak Ridge the radiant host of trees stand hushed and thoughtful, receiving the Sun’s good-night, as solemn and impressive a leave-taking as if sun and trees were to meet no more. The daylight fades, the color spell is broken, and the forest breathes free in the night breeze beneath the stars. ― John Muir

REFERENCES

• My First Summer in the Sierra and Selected Essays by John Muir, 1911.
• Releasing the Sherpas by Campbell McGrath, Poetry Foundation from Poetry (October 2012).

Gravitational Waves

Idealized spacetime curvature
caused by Earth's mass

Gravitational waves are wave-like ripples in the curvature of spacetime.

One precept of Einstein's General Relativity is that spacetime is perturbed by the presence of matter.

Generally, the more mass that is contained within a given volume of space, the greater the curvature of spacetime will be at the boundary of this volume.
― Gravitational Waves, Wikipedia

More than a century following Einstein's proposition of gravitational waves, physicists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) have detected the presences of gravitational waves. These waves are believed to be emanating from the collision of two massive black holes that merged some 1.3 billion years ago.

The Universe has spoken and we have understood.
― David Blair, LIGO collaboration member

Idealized depiction of gravitational waves
by Frank Glowna - Own work, CC BY-SA 3.0

LIGO's discovery appears to be empirical confirmation of the gravitational waves predicted by Einstein's 1918 paper Über Gravitationswellen where he calculated the effect of gravitational waves.

The LIGO system consists of identical detectors in Livingston, Louisiana and Hanford, Washington, that discern tiny vibrations from passing gravitational waves.

It will give us ears to the Universe where before we’ve only had eyes.
― Karsten Danzmann, LIGO collaboration member

Ironically Einstein considered gravitational waves a theoretical construct, perhaps too small to be detected.

Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.
― Albert Einstein

REFERENCES

• Gravitational Waves, Wikipedia.
• Gravitational waves detected -- and that's creating waves in science, Todd Leopold, CNN 11 February 2016.
• Gravitational waves, Einstein’s ripples in spacetime, spotted for first time, Adrian Cho, Science Magazine, 11 February 2016.
• 'The success is very sweet': gravitational wave triumph in quotes, Cosmos Magazine, 12 February 2016.

Planet of Poetry

In the poem The Planet on the Table, Wallace Stevens seems to reflect on a solar system of poetry as if examining it like a painter's still life.

The Planet on the Table

Ariel was glad he had written his poems.
They were of a remembered time
Or of something seen that he liked.

Other makings of the sun
Were waste and welter
And the ripe shrub writhed.

His self and the sun were one
And his poems, although makings of his self,
Were no less makings of the sun.

It was not important that they survive.
What mattered was that they should bear
Some lineament or character,

Some affluence, if only half-perceived,
In the poverty of their words,
Of the planet of which they were part.

The human existential story reveals itself somewhere in the back-and-forth between a world on Earth and a vivid imagination.

It seems it's human nature to imagine participation in the arc of humanity in aggregate in some narrative form however large ("no less makings of the sun") or small ("in the poverty of their words").

Still Life with Tapestry, 1669
Jan van der Heyden

The familiar life we know exists on a solitary home planet within the bounds of its biosphere, on an infinitesimally small life raft called Earth.


REFERENCES

• The Collected Poems of Wallace Stevens by Wallace Stevens, Vintage, 19 February 1990.