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The ground beneath our feet is the
surface of a planet whirling at

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miles an hour around a distant sun.

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Our life is possible only because of the
light and warmth of that sun, a star.

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Yet the sun which shines on us is only
one out of billions of such stars in the

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universe.

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This is one of the world's major
observatories, the David Dunlap

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miles north of Toronto.

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Dr. Donald McRae is a professor of
astronomy at the University of Toronto.

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Observatory. At any moment scattered
throughout the world, there are hundreds

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men and women observing the heavens with
optical and radio telescopes, gathering

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data for the solution of many questions
about the universe.

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routine work for the most part.

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McRae's job tonight, if the sky remains
clear, will be to take photographs of

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six stars with the telescope.

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A mirror over six feet in diameter, with
its surface shape to within one

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millionth of an inch, will catch the
light from a star.

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This light will be reflected from the
large mirror onto a smaller one, which

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turn will focus it back into a camera at
the base of the telescope.

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Out of the study of hundreds of
thousands of observations, astronomers

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pieced together an accurate picture of
the universe.

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Beyond the appearance of starshine and
moonbeam, what will the first men to

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leave the earth find?

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Enough is now known that we can, in
imagination, journey into these spaces.

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250 ,000 miles away, the moon.

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This is the moon that men have
worshipped as a goddess, that countless

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have sighed over and sworn by.

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It will take immense courage to journey
to this place, for on this pitted and

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pocked ball of pumice and stone there is
no atmosphere.

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No air to breathe, no sound to hear.

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By day, the sun's heat would boil water,
if there were water.

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At night, 240 degrees below zero.

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Unshielded, a man couldn't live here for
two minutes.

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But if he were to die, his body would
lie unchanged through thousands of

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for nothing grows and nothing decays.

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If you were to hover in space beyond the
moon, speeding up in imagination its

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movement, you would see a majestic
procession in the sky.

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As the moon circles the earth, so the
earth itself circles the sun.

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The sun is the center of a system of
nine heavenly bodies, called planets,

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wheel around it in vast orbits trapped
by its gravitational pull.

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closest to it, the tiny planet, Mercury.

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On the surface of Mercury, the
temperature is hot enough to melt lead,

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face of it is turned perpetually to the
sun, only 36 million miles away.

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If we looked outward from Mercury, we
would see the second closest planet,

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Venus, shining brighter than the much
more distant stars.

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Venus, in orbit 31 million miles further
out from the Sun, is a mystery, for its

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face is veiled by dust storms, or
perhaps dense cloud.

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Looking outward from Venus,

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The most brilliant and beautiful object
in the sky would be a planet in orbit 25

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million miles still further out.

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Earth.

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Beyond Earth, shining redly in the
night, Mars.

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Colder than Earth and smaller, this is
the planet men have looked on and

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wondered whether they are alone in the
heavens.

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It is reasonably certain that the
markings on its surface, bluish green in

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Martian summer turning rusty brown in
the autumn, indicate vegetation.

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Here, however, the atmosphere has almost
no oxygen, and no creatures like men

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could live here, 140 million miles from
the sun.

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In the place past Mars, where there
should theoretically be a planet, There

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only the asteroids, small bodies ranging
from boulders to chunks 300 miles

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across, hundreds of them swinging in
orbit about the sun.

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500 million miles out from the Sun, the
giant planet Jupiter, ruling 12 moons.

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Jupiter, seen here from one of its
moons, is larger than all the other

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put together.

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Its atmosphere is a thousand miles deep,
a poisonous mixture of methane gas,

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ammonia and hydrogen.

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which at the bottom must have the
density of water.

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Here, under the enormous pressure of the
atmosphere, a human being would be

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crushed beyond recognition.

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These are the rings of Saturn.

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Bands 10 ,000 miles wide, composed of
almost an infinity of meteoric particles

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of gravel and ice circling the sixth
planet.

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Saturn, with its nine moons, is so far
from the sun that it takes 30 Earth

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to circle it.

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And here the temperature never rises
above 240 degrees below zero.

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And if we were to plunge still further
out, hundreds of millions of miles, past

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the planet Uranus, beyond Neptune, we
would finally come to the last of the

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known planets, to the dwarf Pluto, named
for the god of the underworld.

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Its surface moves in perpetual darkness
and unimaginable cold.

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For the sun is four billion miles away,
only a starry speck in the sky.

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Sometimes a strange apparition appears
in the sky, a comet.

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Like a planet, a comet orbits the sun,
but it is only a loose conglomeration of

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ice and dust, invisible, until its head
comes close enough to the sun, whose

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rays then excite it into fluorescence,
and push away from the head a vaporous

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tail, which may become a million miles
long.

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For a few weeks, a comet blossoms, and
then, passing the sun, it will fade and

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coast again, unseen, billions of miles
into the darkness, perhaps not to return

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for a century to the blazing star, which
is its master.

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The sun is an unimaginable inferno, a
thermonuclear furnace churning with the

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storms we see as sunspots, heaving from
its surface columns of gas that arch 300

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,000 miles into space, pulled and
twisted by enormous electrical and

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fields.

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The sun produces the energy of a million
hydrogen bombs exploding every second.

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So it has raged for five billion years,
and so it will rage for perhaps another

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five billion years, flooding its planets
with radiant energy.

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Too near or too far from this furnace,
instant death for men.

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Between 91 and 93 million miles from
this star, filtered through a blanket of

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atmosphere, its energies sustain human
life.

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Hey,

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what's the matter? You're a striker.

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When a particular star is to be
photographed, it is located by its

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on a star chart.

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On such a chart, every black speck is a
star.

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146 .7 plus 1349.

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Forty -five tons of steel and glass must
be aimed precisely.

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at a spot perhaps 200 million billion
miles away.

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Many of the stars astronomers study are
invisible to the naked eye.

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Even the nearest ones, apart from our
sun, are so far away that their light is

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very dim.

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The mirror in the base of the telescope
gathers and focuses hundreds of

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thousands of times the amount of light
seen by the naked eye.

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Almost nothing of a star can be known
directly.

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It is a photograph that is studied.

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Not a portrait of a star, but a
photograph of its light, split into a

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in which each band has its meaning.

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The presence in that distant star of
elements like iron, calcium, carbon.

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From a spectroscopic photograph,
astronomers can tell whether a star is

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towards us or away.

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By exposing on the same plate the
spectrum of the star, and the spectrum

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iron arc, and measuring the displacement
between the two.

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To photograph the spectrum of the arc
takes ten seconds.

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To catch enough of the light from the
star may take up to two hours.

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During the exposure, machinery in the
base of the telescope automatically

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compensates for the rotation of the
Earth, keeping the star centered.

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If we looked more deeply into space,

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leaving behind us the Earth and the
whole of our solar system, and traveled

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the speed of light, it would take four
years before we came to even the closest

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of the billions of suns scattered
through stellar space.

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Although the stars are suns, many of
them are unlike our sun.

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Some, like Beta in the constellation
Lyra, instead of planets, have a second

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swinging around them.

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There are multiple suns, like Castor in
the constellation Gemini.

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There are giant suns 5 ,000 times as
large as ours, and dwarfs, in which one

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cubic inch of matter weighs 40 ton.

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Suns rotating so rapidly that pinwheels
of gas are thrown off, weighing more

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than our whole system of planets.

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Suns that over a period of days or hours
pulse as their internal nuclear

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processes change.

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Rare suns in which the temperature
reaches 5 billion degrees, where nuclear

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fusion makes elements as heavy as iron
and results in the enormous explosion of

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a nova or supernova.

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The brilliant light from such explosions
floods through the gaseous clouds of

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space for billions on billions of miles.

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And the remains of a supernova recorded
ten centuries ago can still be seen as

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the Crab Nebula in the constellation
Taurus.

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As well as stars, in stellar space there
is gas and dust.

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sometimes glowing in starlight,
sometimes dark, obscuring what is behind

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Stars, gas, dust, all moving in apparent
chaos.

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Until a generation ago, it seemed
indecipherable.

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The only suggestion of form was their
grouping in the band we know as the

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Way.

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Now years of patient work have revealed
a pattern in the universe.

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A pattern beyond anything we could have
imagined looking at the heavens with the

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naked eye.

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With data sifted from countless
painstaking observations, astronomers

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filling in the details of a pattern so
vast that everyday ideas of distance and

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time cannot encompass it.

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If we could move with the freedom of a
god, so that a million years pass in a

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second, and if we went far enough, past
the nearest suns, beyond the star

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clouds and nebulae, in time they would
end, and as if moving out from behind a

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curtain, we would come to an endless sea
of night.

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In that sea are islands, continents of
stars, that we have named the galaxies.

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The largest known forms in the universe,
hundreds of billions of suns bound

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together by gravity, rotating around
their common center once in 200 million

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years.

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Our sun.

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with its planets, is near the edge of
one such galaxy, the rim of which we see

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dimly as the Milky Way.

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The galaxies are the birthplace and
graveyard of the stars.

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Here, gas contracts into knots, becomes
hot, and flares into the life of a sun,

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sometimes forming with it planets.

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sometimes planets which must be suitable
for life.

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And here, too, the stars finally consume
themselves and collapse into cold, dark

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dwarfs.

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A hundred billion suns, yet formed so
enormous, that they have been observed

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slipping through one another like
phantoms, their stars light years apart,

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continuing undisturbed in their courses.

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At the very limit of our most powerful
instruments, galaxies still are flung

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across space, themselves as numerous as
stars in the night sky.

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But when we look this deeply into space,
we are looking at a ghostly image of

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the distant past, for the light by which
we see these regions started traveling

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towards us long before the dawn of life
on earth.

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In all of time,

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on all the planets of all the galaxies
in space, what civilizations have risen,

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looked into the night, seen what we see,

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asked the questions that we ask?