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There are some great questions

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that have intrigued and haunted us
since the dawn of humanity.

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The story of our search
to answer those questions
is the story of science.

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Of all human endeavours,
science has had the greatest
impact on our lives,

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on how we see the world,
on how we see ourselves.

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Its ideas, its achievements,
its results, are all around us.

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So, how did we arrive
at the modern world?

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Well, that is more surprising and
more human than you might think.

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The history of science is often
told as a series of eureka moments.

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The ultimate triumph
of the rational mind.

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But the truth is that power
and passion,

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rivalry and sheer blind chance

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have played
equally significant parts.

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In this series, I'll be offering
a different view
of how science happens.

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'It's been shaped as much by what's
outside the laboratory as inside.'

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Whoa!

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This is the story
of how history made science,

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and science made history,

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and how the ideas that
were generated changed our world.

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It is a tale of...

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..and

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This time, one of the
oldest questions we've asked:

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These days, you have to drive a
long way to go and see the night sky
the way that our ancestors did.

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One of science's great achievements
was to create artificial light.

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But unfortunately it does tend to
blot out the beauty of the cosmos.

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It's very peaceful and quiet here,
which is rather surprising

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because you and I are actually
on a giant rock,

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which is spinning through
empty space
at at least 1,000 miles an hour.

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And with our companion, the moon,

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we are also hurtling round the sun

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at a terrifying
67,000 miles an hour.

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And that's not all,

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because we are part of a huge galaxy
called the Milky Way, which consists
of hundreds of billions of stars.

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Out there, we have seen
the birth and death of stars,

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heard the whisper of creation.

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We now realise our universe is a
place of unimaginable strangeness.

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It is so hard to understand
that it's not surprising that,
for most of history,

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there was a very different view
of what is out there.

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This is the story of how we came
to know what we do know about
this bizarre and dazzling universe.

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For me, the story begins in Prague,

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in the opening days of
the 17th century,

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a defining moment in
the creation of modern science.

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It was here that three
critical factors came together.

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Men with daring ideas.

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Collectors of evidence.

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And someone
prepared to pay for it all.

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Europe was in turmoil.

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Forces of religious
and political change
were sweeping across the continent.

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These were violent
and dangerous times.

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But, out of all this tumult would
emerge a new vision of the cosmos.

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It all started when a couple of
the age's more unusual thinkers

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came to work at the court of
the Holy Roman Emperor, Rudolph II.

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In those days, Prague was a
major centre of power and culture.

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The Emperor Rudolph
was hungry for new discoveries.

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New ideas to dazzle
and impress his fellow rulers.

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His enormous wealth and patronage
drew to Prague one of the

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brightest stars of the age,
the astronomer Tycho Brahe,

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an eccentric Danish nobleman.

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Tycho was a wonderfully
colourful character.

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When he was a student, he lost
a large chunk of his nose in a duel

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and had it
replaced with a metal one.

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Legend has it he kept a dwarf
under his table, and he believed
that that dwarf was clairvoyant.

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He also apparently kept an
elk, which fell down the
stairs when drunk, and died.

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There is however one thing about
Tycho which is absolutely certain -
he was a passionate stargazer.

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Science needs evidence, and Tycho
was a new sort of data gatherer.

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He built a vast observatory,
and equipped it with the
best instruments money could buy.

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And so was his commitment,
night after night for over 20 years.

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He was putting together
a unique body of evidence

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that would in time reveal
the secrets of how the planets move.

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Right.
So we've got the moon over there.

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Now this is how you'd make an
observation with Tycho's Quadrant.

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It is of course pointing at the moon.

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You take the sighting arm.

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You sight it exactly upon the moon.

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You would look through the upper slit
across the upper part
of that central brass peg... Yeah.

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Then the lower slit through
the lower peg,

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so the upper and the lower cusps
of the moon,

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the points of the moon,
were between them.

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You've got it lined up, essentially.

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Absolutely lined up.

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OK. So I get that as 15 degrees...

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and 40 minutes of arc. That
sounds perfectly reasonable. OK.

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And that is logged as the moon,
on the 26th of May at just past
ten o'clock. Just past ten o'clock.

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So he would go on plotting these
details throughout the night.

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Yes. Not just the moon,
the moon would set,
but you'd do it for planets,

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as things appropriately
came in the sky, and build up these
great observing logs of raw data.

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And out of that, of course,
is what the heart of science is.

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Tycho starts his tradition of
science, not just being about
information and theories, about data.

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Information and analysis from
fresh observations.

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Books of it, presumably?
Absolutely.

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Having seen you in action now, what
I'd like to do now is look at a
star, the pole star, the north star.

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The pole star, which of
course everything rotates around,
the star over here.

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What Tycho was doing represents
something really important

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in the emergence of science -

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a commitment
to cold, hard, obstinate facts.

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I can see it now I'm
lining it up with that and...

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That is
51 degrees and 36 arc minutes.

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Right, excellent. So that's my first
star. It is indeed. Not bad at all.

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Thank you. I've got 776 to go.

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Congratulations! Thank you.
THEY LAUGH

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It's a shame that the craftsmen who
built such beautiful instruments,

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and men like Tycho who used them,

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get so little credit.

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Because the evidence that
he gathered would, in time,

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undermine a belief system
that had dominated Western thought
for over 2,000 years.

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Many early civilisations
developed sophisticated ideas
about the heavens.

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But the Western view was, above all,
defined in ancient Greece.

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You can get a sense
of Greek cosmology if you come here.

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This is the sacred site of Delphi.

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Its famous oracle drew people
from all over the Greek world.

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This is the Temple of Apollo, and
it's where you'd have come and often
received extremely cryptic advice.

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It is also where you would have
found the Omphalos, a stone which

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marked the centre of the world,
and therefore for many Greeks,
the centre of the cosmos.

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Down the centuries, Greek
philosophers argued long and hard

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about the shape of the universe
and what is out there

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until, in the end,
one particular view became dominant.

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Around the fourth century BC,
a number of Greeks developed a model
of the universe in which the Earth

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was stationary and everything else
moved in giant, perfect circles
around the stationary Earth.

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The perfect
circular orbits of the other planets

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reflecting the perfection of
the gods that had put them there.

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It was simple, intuitive and,
of course, it was wrong.

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Yet it endured.

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So why did this idea
persist for so long?

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Well, it's partly
because it's comforting
to be at the centre of things.

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But also because the alternative
made absolutely no sense.

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If we really are on a rock
hurtling through space,

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then surely we would be
constantly buffeted by huge winds.

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So, commonsense said
the Earth must be stationary
with everything going round it.

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But there was a problem with this
idea, a pretty fundamental one.

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A remarkable discovery,
made just over a century ago,

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gives us a striking insight
into the Greek view of the cosmos.

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It was the result of a freak storm.

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Battered by strong winds, a group of
sponge divers took shelter on the
small Greek island of Antikythera.

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When the storm finally subsided,
one of the divers decided
to explore the unfamiliar waters.

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There were no sponges,
but strewn across the seabed were
the remains of an ancient shipwreck.

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Its cargo 2,000 years old.

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They also found a strange bronze
mechanism, which would turn
out to be one of the rarest and,

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in its own way,
most precious treasures ever
recovered from the ancient world.

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It is a beautifully engineered
scientific instrument, with wheels
and cogs carved from bronze.

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Nothing like this would be made
for another thousand years.

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But its exact purpose
has long been a puzzle.

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Michael Wright has spent more
than 20 years attempting to

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create a model of the original,
and to understand its workings.

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Hello. Hello. Nice to meet you.
And this is the mechanism, is it?

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This is the mechanism.
Do you mind if I twiddle?

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Of course, have a go.
You won't break it.

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So what's it doing when I turn this?

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This is the representation
of the sky as

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people tended to think of it.

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You can picture, if you like,

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the Earth being
at the centre of the dial,

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and the planets
and the sun and moon going round us.

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That's the moon there.
That's the moon.

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And as the moon goes round,
that's presumably what, full moon?

155
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That's full moon because
it's opposite the sun pointer.

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What impresses me is,
so somebody designed this well
over 2,000 years ago. Yes.

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Built it well over 2,000 years ago.

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Of course, the bit you're
looking at here is my restoration.

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So, I don't guarantee the original
was exactly like this, but I do say

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with some confidence
it was along these lines.

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That is very clever!

162
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But what this mechanism illustrates
is how the Greeks wrestled
with a tricky astronomical problem.

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One that comes about if you think
that the Earth is at
the centre of the universe.

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It's this.

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The planets sometimes appear to move
backwards in the night sky.

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It's a problem that the Greeks
recognised and agonised over.

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Most of the time,
they're going forwards,

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which is sort of what I would
expect, some of them going fast.

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Ooh and that one's...
Which one's that? Oh, that's Mars.
Now we see it's stopped.

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And there it goes backwards.

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All the planets have these
phases of going backwards. Right.

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But Mars has a particularly bold one.

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In general, you see them moving
a little further east every night.

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But there come times with each of
the planets when they seem to stop

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amongst the stars and go westward,
for a, a period of days.

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And then they stop again
and go back eastward.

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And this
instrument replicates that behaviour.

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This complexity didn't
make the Greeks question
their perfect circles.

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00:15:35,040 --> 00:15:41,080
Instead, they added more,
a lot more - well over 50.

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This tangle of circles moving upon
circles explained how the planets

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appeared to move backwards,

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and preserved the belief
in an Earth-centred universe.

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The person who made this
knew the latest astronomy,

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he knew how to combine circular
motions to get something like
the true motion of the planets.

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This view of the cosmos
was one of the most enduring beliefs
in human history.

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00:16:18,880 --> 00:16:22,440
It took root in the Arab world
after the collapse of Rome.

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And it was adopted by
the Catholic Church in Europe.

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It was so deeply embedded in
European thought that it would take
a radical shift to dislodge it,

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and that was brought
about by a great force of history.

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00:16:45,640 --> 00:16:47,160
The Reformation.

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00:16:48,840 --> 00:16:52,960
It began as a revolt against
abuses by the Catholic Church.

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00:16:56,200 --> 00:17:01,920
And ended splitting Western Europe
into two, Catholic and Protestant.

193
00:17:03,920 --> 00:17:10,400
The new Protestant movement
stressed the role of the individual
outside the authority of the Church.

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00:17:15,720 --> 00:17:19,000
The Reformation created
two conflicting views about

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00:17:19,000 --> 00:17:22,600
the route to personal salvation,
about how you got to heaven.

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00:17:24,600 --> 00:17:28,120
If there could be doubt about such
a fundamental question,

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then perhaps there were also doubts
about other ancient truths.

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00:17:31,560 --> 00:17:34,160
The Reformation created
an intellectual climate

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00:17:34,160 --> 00:17:37,400
in which it became possible
to question authority.

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00:17:45,000 --> 00:17:49,520
And, critically for the question,
what is out there,
the wars and violence that

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followed the Reformation brought a
rather special refugee to Prague.

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00:17:55,160 --> 00:18:01,520
Arriving to join Tycho the stargazer
was an impoverished German
mathematician, Johannes Kepler.

203
00:18:05,120 --> 00:18:11,360
When Johannes Kepler
arrived here in Prague in 1600,
he was in dire straits.

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00:18:11,360 --> 00:18:16,000
His two young children had
recently died, and he was in
desperate need of a job.

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When he arrived here,
there was no procession,
there was no imperial greeting.

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00:18:27,520 --> 00:18:35,320
I am reasonably sure that amongst
his possessions however he would
have had one of these horoscopes.

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00:18:35,320 --> 00:18:42,680
Ironically enough, a man who would
be greeted as one of the greats
of science practised astrology.

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00:18:45,240 --> 00:18:49,000
Kepler had come to Prague
to work for Tycho.

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00:18:50,520 --> 00:18:54,840
But, soon after he arrived,
Tycho died.

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00:18:54,840 --> 00:19:00,480
While the court mourned,
Kepler purloined Tycho's vast
collection of star data.

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00:19:04,000 --> 00:19:09,720
Kepler was now
the court mathematician
AND Rudolph's main astrologer.

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00:19:12,120 --> 00:19:16,600
To us, this might seem
an odd combination of roles.

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00:19:18,000 --> 00:19:24,400
But back then, great rulers
often had an astrologer,
someone like Johannes Kepler,

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00:19:24,400 --> 00:19:28,160
to cast their horoscopes
to peer into the future.

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00:19:32,200 --> 00:19:36,520
Astrology was all about
predicting where and how
the planets would move.

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00:19:38,080 --> 00:19:42,880
It depended on accurate star charts
and good mathematics.

217
00:19:48,560 --> 00:19:52,480
We still use astrological language
when we talk about lunatics,

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00:19:52,480 --> 00:19:56,320
people who've been driven mad by
"lunar", the moon.

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00:19:56,320 --> 00:20:01,200
Or disasters,
terrible things that happen to us
because of "astra", the stars.

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00:20:01,200 --> 00:20:05,040
But the effects of astrology
are more profound than that.

221
00:20:05,040 --> 00:20:08,920
It is precisely because people
like Rudolph believed in it

222
00:20:08,920 --> 00:20:12,800
that they were prepared to pay
for detailed studies of the stars.

223
00:20:12,800 --> 00:20:18,400
And these studies would prove vital
when it came to developing
a new vision of the cosmos.

224
00:20:20,920 --> 00:20:26,040
In Prague, there was now a
powerful alignment of forces.

225
00:20:26,040 --> 00:20:31,960
The wealth and patronage
of the Emperor Rudolph
had brought together in one place

226
00:20:31,960 --> 00:20:35,720
star data gathered by Tycho Brahe,

227
00:20:35,720 --> 00:20:40,480
and a man with a mathematical
ability to use it, Johannes Kepler,

228
00:20:42,000 --> 00:20:46,200
alongside the intellectual turmoil
unleashed by the Reformation.

229
00:20:53,320 --> 00:20:58,640
All these forces coming together
help explain why a new vision
of the universe finally emerged here

230
00:20:58,640 --> 00:21:02,200
in Prague at the beginning
of the 17th century.

231
00:21:04,320 --> 00:21:10,160
A model of the universe which placed
not the Earth but the sun
at the centre of everything.

232
00:21:14,440 --> 00:21:16,600
Now, this was not a new idea.

233
00:21:16,600 --> 00:21:21,120
It had been debated by Greek,
Indian and Arab astronomers,

234
00:21:21,120 --> 00:21:24,200
and rediscovered
by Nicholas Copernicus,

235
00:21:24,200 --> 00:21:28,920
a Polish cleric who was trying to
tidy up the tangle of Greek circles.

236
00:21:32,080 --> 00:21:37,480
Copernicus is often hailed
as the man who changed
our vision of the universe forever.

237
00:21:37,480 --> 00:21:41,000
But his system was actually
nightmarishly confusing.

238
00:21:41,000 --> 00:21:45,640
He had planets
whizzing round an imaginary point
somewhere near the sun.

239
00:21:45,640 --> 00:21:48,320
It was as complicated
as the Greek model.

240
00:21:49,840 --> 00:21:57,640
Copernicus died before Kepler
was born, and the world had not
been persuaded by his arguments.

241
00:21:57,640 --> 00:22:00,160
But they had got Kepler thinking.

242
00:22:03,560 --> 00:22:10,840
Kepler was convinced that the sun,
the symbol of God, produces a force
which drives the planets round it.

243
00:22:10,840 --> 00:22:14,880
He was also convinced
that only a sun-centred cosmos

244
00:22:14,880 --> 00:22:18,400
could possibly account for the
bizarre movement of the planets.

245
00:22:18,400 --> 00:22:22,320
So, using Tycho's data,
he set himself a challenge -

246
00:22:22,320 --> 00:22:28,240
explain the movement of Mars,
the planet
with the oddest orbit of them all.

247
00:22:30,520 --> 00:22:34,320
This is the confusion
he was struggling with.

248
00:22:34,320 --> 00:22:37,720
But he thought the ancient
problem with Mars could be solved.

249
00:22:39,520 --> 00:22:43,240
He believed he could explain
this movement by having the Earth

250
00:22:43,240 --> 00:22:47,280
and Mars travel in circular
orbits around the sun.

251
00:22:47,280 --> 00:22:52,120
Armed with Tycho's data, he set
out to prove it mathematically.

252
00:22:52,120 --> 00:22:55,360
It was unbelievably tedious work.

253
00:22:55,360 --> 00:22:58,680
Hundreds and hundreds of
pages of calculations,

254
00:22:58,680 --> 00:23:01,120
which took him
more than five years.

255
00:23:01,120 --> 00:23:05,440
As he later wrote, "If thou,
dear reader, are bored with these

256
00:23:05,440 --> 00:23:11,040
"wearisome calculations, take
pity on me who did it 70 times."

257
00:23:18,040 --> 00:23:24,800
Kepler tried everything.
He varied the speed of the planets,

258
00:23:24,800 --> 00:23:27,360
he shifted the
positions of the orbits,

259
00:23:27,360 --> 00:23:33,880
but whatever he did
he couldn't make circular orbits
match Tycho's observations.

260
00:23:33,880 --> 00:23:40,240
So he did something which, for
a man of his time, was daring.

261
00:23:40,240 --> 00:23:46,680
He dropped the enduring belief
in divine circles,
and tried other shapes,

262
00:23:46,680 --> 00:23:51,920
until finally he found one -

263
00:23:51,920 --> 00:23:53,440
an ellipse.

264
00:24:00,560 --> 00:24:06,200
At last he had created
a model of the cosmos
that matched the evidence.

265
00:24:09,920 --> 00:24:15,120
Kepler had demolished an
edifice that had stood for
more than 2,000 years,

266
00:24:15,120 --> 00:24:22,200
and replaced it with his first law
of planetary motion - all planets
travel in ellipses around the sun.

267
00:24:36,360 --> 00:24:40,880
You might have hoped that
when Kepler published, the whole
mad structure of the Greeks

268
00:24:40,880 --> 00:24:43,560
would come tumbling down.
Well, it didn't.

269
00:24:43,560 --> 00:24:47,480
Many astronomers complained that he
had brought physics into astronomy.

270
00:24:47,480 --> 00:24:49,160
Others simply ignored him.

271
00:24:49,160 --> 00:24:53,240
It wasn't until long after
his death that his work
was finally appreciated.

272
00:24:53,240 --> 00:24:58,000
As many have discovered,
being right is often not enough.

273
00:25:01,760 --> 00:25:07,760
To get this new vision of
the heavens noticed would require
a very different set of events.

274
00:25:07,760 --> 00:25:10,880
Astronomy would have to go tabloid.

275
00:25:19,320 --> 00:25:23,160
'The story of what's out there
now moves south.'

276
00:25:25,240 --> 00:25:28,200
Renaissance Italy was awash
with money from trade.

277
00:25:29,560 --> 00:25:35,040
'The courts of Florence and Venice
became magnets for those
with talent and ambition.'

278
00:25:43,080 --> 00:25:48,760
Renaissance Italy was the perfect
place for a man on the make,
a man like Galileo Galilei.

279
00:25:48,760 --> 00:25:51,840
Now, he had aspirations
to greatness, but at the time,

280
00:25:51,840 --> 00:25:54,680
he was a middle-aged professor
of mathematics

281
00:25:54,680 --> 00:25:57,720
with three illegitimate children
and few prospects.

282
00:25:57,720 --> 00:26:02,200
Yet, within a year, he would enjoy
a spectacular rise,

283
00:26:02,200 --> 00:26:05,800
followed by
an even more spectacular fall.

284
00:26:10,080 --> 00:26:15,120
It begins with the unexpected
arrival of a stranger.

285
00:26:21,480 --> 00:26:26,320
In July 1609, word reached Galileo
that a stranger had arrived
in Venice,

286
00:26:26,320 --> 00:26:30,120
trying to patent a wonderful new
device called the Dutch spyglass,

287
00:26:30,120 --> 00:26:32,720
which could make distant objects
seem closer.

288
00:26:34,800 --> 00:26:41,880
Now, if ever there was a city
where such an instrument would
generate excitement, it was Venice.

289
00:26:45,680 --> 00:26:51,240
Venice is reliant on the sea, which
makes it vulnerable to attack from
the sea, which is why any device

290
00:26:51,240 --> 00:26:56,400
that would give you advance warning
of approaching enemy ships would
clearly be of enormous value.

291
00:27:02,320 --> 00:27:06,160
Galileo recognised the potential of
the spyglass, but he also recognised

292
00:27:06,160 --> 00:27:09,040
that if he was going to make
any money out of it,

293
00:27:09,040 --> 00:27:12,080
he was going to have to act
incredibly fast.

294
00:27:12,080 --> 00:27:14,480
OK, let's go.

295
00:27:19,160 --> 00:27:25,200
Galileo had to get a fully working
spyglass to the Doge of Venice
before the stranger did.

296
00:27:27,160 --> 00:27:32,000
'That meant he had to design
and build one from scratch.

297
00:27:32,000 --> 00:27:37,160
'Clues to how he did this come
from a later shopping trip.'

298
00:27:37,160 --> 00:27:41,000
On his shopping list,
which, extraordinarily enough,
still exists,

299
00:27:41,000 --> 00:27:45,240
he had written, "Chickpeas
and slippers for my son."

300
00:27:45,240 --> 00:27:51,720
But he's also written down, "Glass,
artillery balls and an organ pipe,"

301
00:27:51,720 --> 00:27:55,880
and this is what you need if you are
going to build a Dutch spyglass,

302
00:27:55,880 --> 00:27:59,440
a device later renamed
the telescope.

303
00:28:03,520 --> 00:28:07,840
The best place to buy glass
was the island of Murano,
just across the lagoon.

304
00:28:10,760 --> 00:28:16,240
'Here, a group of craftsmen had
a skill so precious, they were
barred from leaving Venice.'

305
00:28:21,400 --> 00:28:26,960
That skill was the ability to make
glass of crystal-like purity.

306
00:28:31,000 --> 00:28:32,440
Perfect!

307
00:28:32,440 --> 00:28:33,560
Wonderful!

308
00:28:36,480 --> 00:28:38,600
Whoo!

309
00:28:38,600 --> 00:28:42,560
We have a new glass-blowing master!

310
00:28:42,560 --> 00:28:44,280
That was fun, thank you.

311
00:28:50,760 --> 00:28:52,880
He smashes it up!

312
00:28:55,120 --> 00:28:58,320
The glass was known as Cristallo.

313
00:28:58,320 --> 00:29:03,720
It was bought by the aristocrats
of Europe to adorn their tables.

314
00:29:03,720 --> 00:29:08,880
It was the first really clear,
colourless glass ever produced,

315
00:29:08,880 --> 00:29:16,800
and it was probably this glass that
allowed Galileo to build a telescope
of stunning optical quality.

316
00:29:20,000 --> 00:29:24,120
400 years ago, glassmakers started
with a bottle,

317
00:29:24,120 --> 00:29:27,360
and then opened it up into a sheet.

318
00:29:29,920 --> 00:29:33,000
'The first stage to making
a telescope lens.'

319
00:29:36,440 --> 00:29:40,240
I've got glass from Murano,
and I've got an artillery ball.

320
00:29:40,240 --> 00:29:45,800
And I'm off to meet a lens grinder
who apparently can use this to turn
this into a telescope lens.

321
00:29:47,840 --> 00:29:50,760
Buongiorno. Ah, buongiorno, Michael.

322
00:29:50,760 --> 00:29:53,200
Hello. Have that one. Ah, va bene!

323
00:29:54,360 --> 00:30:00,600
'In the autumn of 1609,
Galileo himself began to grind
and polish lenses.'

324
00:30:02,720 --> 00:30:05,480
HE SPEAKS ITALIAN 
Ah, OK.

325
00:30:07,920 --> 00:30:12,800
'By trying out different lenses,
made with different sized
artillery balls, he was able

326
00:30:12,800 --> 00:30:16,920
'to produce magnifications
of six and then 20 times.'

327
00:30:20,400 --> 00:30:26,280
It might seem surprising that a
mathematician like Galileo would
want to get his hands dirty in

328
00:30:26,280 --> 00:30:31,800
this way. But it's part of
the important emerging trend
in the 16th and 17th century.

329
00:30:31,800 --> 00:30:34,720
People were no longer satisfied
just to intellectualise,

330
00:30:34,720 --> 00:30:38,800
they were making instruments
and they were testing them out.

331
00:30:43,880 --> 00:30:51,720
The fact that Galileo, a professor
of mathematics, was grinding his
own lenses, is of real significance.

332
00:30:51,720 --> 00:30:56,200
This joining of the skills
of scholars and craftsmen

333
00:30:56,200 --> 00:30:59,680
was key to the emerging power
of European science.

334
00:31:07,920 --> 00:31:11,560
Galileo now took his new lenses,
and through a process
of trial and error,

335
00:31:11,560 --> 00:31:15,760
worked out what the ideal distance
was between them

336
00:31:15,760 --> 00:31:20,440
to get maximum magnification
along with maximum sharpness.

337
00:31:20,440 --> 00:31:25,800
He then packaged them together
into a new spyglass.

338
00:31:25,800 --> 00:31:29,680
Now, what was truly impressive is
that it had only been a few weeks

339
00:31:29,680 --> 00:31:34,880
since he'd first heard of the
Dutch spyglass, and yet he produced
something which was far superior.

340
00:31:34,880 --> 00:31:38,600
He now got together some influential
Venetians, took them up the tower,

341
00:31:38,600 --> 00:31:41,240
and pointed his new spyglass
out at sea.

342
00:31:55,080 --> 00:31:58,880
Its value was not lost
on the Venetians.

343
00:31:58,880 --> 00:32:03,200
You could now see ships two hours
sooner than with the naked eye.

344
00:32:06,560 --> 00:32:10,480
Galileo's climb to fame and fortune
had begun.

345
00:32:12,000 --> 00:32:17,040
'And then, fatefully, he lifted
his telescope to the heavens.'

346
00:32:28,520 --> 00:32:33,400
His telescope now uncovered dramatic
new evidence about the cosmos.

347
00:32:35,560 --> 00:32:40,280
'Evidence that would bring the idea
of a sun-centred universe
to the fore.

348
00:32:44,480 --> 00:32:49,520
'I'm going to see the night skies as
he would have done 400 years ago.'

349
00:32:55,800 --> 00:32:58,880
Francesco, it has to be.
Who else in the middle of the night?

350
00:32:58,880 --> 00:33:00,640
Hello, Michael. Michael Mosley.

351
00:33:00,640 --> 00:33:05,600
I have my Galileo telescope,
which magnifies about sixfold.

352
00:33:05,600 --> 00:33:07,440
I'm guessing yours does a bit more.

353
00:33:07,440 --> 00:33:09,720
This one does 20, 20 times.

354
00:33:09,720 --> 00:33:14,840
So this is optically identical,
pretty much, to what Galileo had
to deal with. That's right. Yeah.

355
00:33:14,840 --> 00:33:18,240
Because the lenses have been
analysed and studied and

356
00:33:18,240 --> 00:33:23,040
reproduced with the same properties
as the ones that Galileo used.

357
00:33:23,040 --> 00:33:27,880
Can I have a look? Yes.
I haven't really properly looked
through something like this before.

358
00:33:27,880 --> 00:33:31,920
Shall I start with that one there?
Right.

359
00:33:31,920 --> 00:33:33,320
Ah! Gorgeous!

360
00:33:35,520 --> 00:33:41,080
This is what Galileo's lenses
were able to show
of the surface of the moon.

361
00:33:44,320 --> 00:33:47,600
Night after night,
he observed its phases.

362
00:33:53,320 --> 00:33:57,120
His drawings are not just detailed,
they are beautiful.

363
00:33:59,880 --> 00:34:05,760
For me, it's basically, there's
a lot of shimmer going on and it
sort of pops in and out of focus.

364
00:34:05,760 --> 00:34:11,600
I'm absolutely amazed that
Galileo could draw the images
at that level of accuracy.

365
00:34:11,600 --> 00:34:13,400
I mean, really phenomenal.

366
00:34:16,720 --> 00:34:19,520
This was how Galileo saw Jupiter.

367
00:34:21,680 --> 00:34:27,040
No-one had seen these bright objects
either side of it before.

368
00:34:27,040 --> 00:34:29,840
They are moons, circling the planet.

369
00:34:31,360 --> 00:34:35,400
And if there are moons circling
a planet which is not the Earth...

370
00:34:38,800 --> 00:34:44,120
did that perhaps suggest
that the Earth was not really
the centre of everything?

371
00:34:46,040 --> 00:34:51,040
I must admit, having seen this,
I have enormous, enormous respect
for Galileo now.

372
00:34:51,040 --> 00:34:56,440
I always saw him as a bit of a
chancer, to be honest, but having
seen what he did with a machine

373
00:34:56,440 --> 00:34:59,040
with these limitations,
it makes you think, wow!

374
00:35:01,400 --> 00:35:07,360
He now took full advantage
of another Renaissance invention,
the printing press.

375
00:35:10,320 --> 00:35:14,920
He put his findings together into
this book, The Starry Messenger.

376
00:35:14,920 --> 00:35:19,200
Unusually for an astronomical book
of its time, it is well written,

377
00:35:19,200 --> 00:35:22,400
it has lovely pictures
and very little maths.

378
00:35:22,400 --> 00:35:26,400
In fact, it soon became
a 17th century bestseller.

379
00:35:31,360 --> 00:35:34,120
'The book made him famous,
and that encouraged him

380
00:35:34,120 --> 00:35:38,320
'to do what he loved best,
courting controversy and attention.

381
00:35:40,560 --> 00:35:45,560
'Galileo had become convinced
that the sun was at the centre
of the cosmos.

382
00:35:45,560 --> 00:35:51,160
'Now he began to promote that idea
amongst influential people.'

383
00:35:58,360 --> 00:36:01,840
His timing was terrible.

384
00:36:01,840 --> 00:36:06,160
The Reformation had challenged
the power of the Catholic Church.

385
00:36:08,400 --> 00:36:14,240
Many within the Church
now wanted to re-assert control.

386
00:36:14,240 --> 00:36:18,160
A fight with Galileo suited them.

387
00:36:22,520 --> 00:36:26,480
And then, in 1632, it all went
terribly wrong for Galileo.

388
00:36:26,480 --> 00:36:29,480
He published a book
that destroyed his life.

389
00:36:29,480 --> 00:36:35,480
The book enraged the Pope, and
remained on the index of prohibited
books for more than 200 years.

390
00:36:35,480 --> 00:36:39,360
It's called The Dialogue.

391
00:36:43,280 --> 00:36:47,800
He had been given permission
to write this book,
on condition it was balanced.

392
00:36:50,280 --> 00:36:54,840
The book is presented as a series
of discussions about the cosmos.

393
00:36:56,960 --> 00:37:01,320
One side arguing for a stationary
Earth at the centre,

394
00:37:01,320 --> 00:37:03,920
the other favouring the sun.

395
00:37:05,560 --> 00:37:13,320
But despite what he'd promised,
Galileo clearly came down on
the side of the sun at the centre.

396
00:37:17,880 --> 00:37:24,160
But worst of all, what he was really
saying is there are truths which go
beyond the realms of religion,

397
00:37:24,160 --> 00:37:30,000
or, as he once put it, "The Bible
teaches us how to go to heaven,
not how the heavens go."

398
00:37:32,240 --> 00:37:37,160
Make no mistake, this was a huge
challenge to the Church.

399
00:37:37,160 --> 00:37:43,000
Galileo was saying that science
can discover truths about nature

400
00:37:43,000 --> 00:37:46,640
using its own methods
of investigation.

401
00:37:46,640 --> 00:37:52,680
And so, in 1633, he was brought
to Rome to stand trial
before the Inquisition.

402
00:37:55,320 --> 00:37:58,760
The story of Galileo is often told
as scientific hero

403
00:37:58,760 --> 00:38:03,440
takes on reactionary Church over the
question of a sun-centred universe.

404
00:38:03,440 --> 00:38:05,480
But it wasn't really like that.

405
00:38:05,480 --> 00:38:12,720
The trial of Galileo was actually
about authority, who owns the truth
about the heavens.

406
00:38:15,360 --> 00:38:18,200
He was tried and found guilty.

407
00:38:27,200 --> 00:38:33,120
The sentence broke him.
Old, ill, in pain, he was condemned
to life imprisonment,

408
00:38:33,120 --> 00:38:38,040
and he spent much of it here
at his villa in Arcetri,
in the foothills above Florence.

409
00:38:38,040 --> 00:38:44,080
Ironically, the banning of
The Dialogue ensured that the book
was widely read

410
00:38:44,080 --> 00:38:47,640
in other countries, as people
scrambled to get hold of a copy

411
00:38:47,640 --> 00:38:50,000
and discover what
all the fuss was about.

412
00:38:59,760 --> 00:39:03,080
It was a moment of human reckoning.

413
00:39:03,080 --> 00:39:07,920
We no longer sat
at the centre of the universe,

414
00:39:07,920 --> 00:39:11,680
just on another planet
circling the sun.

415
00:39:17,520 --> 00:39:20,880
The attempts to gag Galileo
were utterly futile.

416
00:39:20,880 --> 00:39:25,960
Within a generation, the educated
classes throughout Europe had
accepted that the sun and not

417
00:39:25,960 --> 00:39:29,520
the Earth is at the centre
of the solar system.

418
00:39:34,200 --> 00:39:40,280
It happened, not in a single
moment of genius, but as a result
of a series of connections.

419
00:39:40,280 --> 00:39:44,880
The patronage of the princely courts
of the Renaissance.

420
00:39:44,880 --> 00:39:48,520
A combination of different talents -

421
00:39:48,520 --> 00:39:53,880
Tycho Brahe, Johannes Kepler,
and Galileo Galilei.

422
00:39:55,400 --> 00:39:58,200
Technological innovation,

423
00:39:58,200 --> 00:40:00,840
raw data from telescopes,

424
00:40:00,840 --> 00:40:05,240
and the power of the printing press
to spread the new knowledge.

425
00:40:10,920 --> 00:40:14,680
When you think about it, it is
astonishing that nearly a century

426
00:40:14,680 --> 00:40:19,840
separates Copernicus first
publishing his book claiming that
the Earth goes round the sun,

427
00:40:19,840 --> 00:40:24,320
and Galileo's trial,
after which, the idea finally
gets widespread acceptance.

428
00:40:24,320 --> 00:40:29,200
And when you look at it in
that light, you realise that this
claim, you get these violent

429
00:40:29,200 --> 00:40:35,000
upheavals in intellectual thought
which change everything overnight,
well, that claim is clearly myth.

430
00:40:35,000 --> 00:40:40,200
It is largely created by the comfort
and distance of hindsight.

431
00:40:41,880 --> 00:40:44,320
So, no sudden revolution, then.

432
00:40:46,160 --> 00:40:53,160
As so often in science, what
happened is that people who hold
the old views slowly die off,

433
00:40:53,160 --> 00:40:57,680
and a new generation comes in
that sees things differently.

434
00:41:07,440 --> 00:41:14,800
There was now a new force driving
interest in the heavens -
global trade.

435
00:41:19,880 --> 00:41:24,640
Economic power in Europe
was shifting away from
the Mediterranean countries,

436
00:41:24,640 --> 00:41:29,440
towards the Atlantic nations,
like Spain, Portugal and England.

437
00:41:32,920 --> 00:41:38,640
As new trade routes opened up,
ships' captains needed
better star maps to steer by.

438
00:41:40,520 --> 00:41:44,920
Governments funded newer
and better telescopes.

439
00:41:46,560 --> 00:41:48,920
Astronomical evidence poured in.

440
00:41:48,920 --> 00:41:52,000
New questions were being asked.

441
00:41:52,000 --> 00:41:56,000
Why did the Earth and the planets
move in giant ellipses?

442
00:41:59,120 --> 00:42:02,600
And what was it that held
the cosmos together?

443
00:42:10,320 --> 00:42:14,520
One of the cargoes those ships
brought to Europe was coffee.

444
00:42:18,560 --> 00:42:25,680
'Coffee led to coffee shops, places
where traders, ships' captains
and assorted thinkers met,

445
00:42:25,680 --> 00:42:27,960
'and fuelled up on caffeine.

446
00:42:29,520 --> 00:42:31,640
'They became known
as penny universities.'

447
00:42:33,280 --> 00:42:34,880
Thank you very much.

448
00:42:38,760 --> 00:42:44,440
Learned gentlemen would come to
coffee shops to debate the central
burning questions of the day.

449
00:42:44,440 --> 00:42:49,600
And one of the key questions was,
what is it that keeps
the planets in their place?

450
00:42:49,600 --> 00:42:53,760
Well, in 1684, this led to a bet.

451
00:42:53,760 --> 00:42:58,720
At stake was two pounds, about
a week's salary, but this
would turn out

452
00:42:58,720 --> 00:43:02,160
to be one of the most significant
wagers ever made.

453
00:43:08,040 --> 00:43:13,560
To win the bet, what they had to do
was to prove that the elliptical
path that planets take around

454
00:43:13,560 --> 00:43:19,560
the sun, which Kepler described,
obey a simple mathematical rule.

455
00:43:19,560 --> 00:43:24,840
Now, smart though they were,
they soon realised they were
going to need help.

456
00:43:28,000 --> 00:43:33,280
'One of the men who'd taken the bet,
the astronomer Edmund Halley,
set off in search of help,

457
00:43:33,280 --> 00:43:40,400
'to Cambridge, to find the Lucasian
professor of mathematics,
a certain Isaac Newton.'

458
00:43:43,200 --> 00:43:48,320
Halley manages to track Newton down,
and he tells him about the bet.

459
00:43:48,320 --> 00:43:51,200
Then Newton, to Halley's
complete amazement, says,

460
00:43:51,200 --> 00:43:56,240
"Actually, I've solved that problem,
I've done the calculations,
and they're here somewhere."

461
00:43:56,240 --> 00:43:59,200
And he sort of rummages around
amongst these papers.

462
00:43:59,200 --> 00:44:03,160
But he can't find them.
So he says to Halley,
"I'll send them on to you."

463
00:44:03,160 --> 00:44:08,560
The important thing about this
visit is it seems to have triggered
something in Newton's brain.

464
00:44:10,640 --> 00:44:13,720
The memory of a time
20 years earlier.

465
00:44:17,200 --> 00:44:22,200
A time when Newton returned
to his family farm to escape
an outbreak of the plague.

466
00:44:24,800 --> 00:44:28,400
It was certainly safer,
but I'm not sure how pleased
he was to be back.

467
00:44:28,400 --> 00:44:32,880
As a young man, he'd threatened to
burn the house down with his mother
and stepfather in it.

468
00:44:32,880 --> 00:44:37,560
Described as artificial, unkind,
arrogant, he was also

469
00:44:37,560 --> 00:44:41,280
one of the most brilliant minds
of his or any other generation.

470
00:44:41,280 --> 00:44:47,560
'There are few more famous legends
in the whole history of science

471
00:44:47,560 --> 00:44:49,960
'than that of Newton
in the orchard.

472
00:44:51,520 --> 00:44:58,320
'That moment of genius when the
young Isaac Newton first worked out
a comprehensive theory of gravity.'

473
00:45:00,320 --> 00:45:03,560
It's one of the great
eureka moment stories.

474
00:45:03,560 --> 00:45:06,280
Newton's in the orchard
when he sees the apple fall.

475
00:45:06,280 --> 00:45:11,920
The falling apple is said to have
triggered a cascade of thoughts
in Newton's mind.

476
00:45:11,920 --> 00:45:14,520
Why is it apples always fall down?

477
00:45:14,520 --> 00:45:18,720
Why doesn't it sometimes
go sideways, or even upwards?

478
00:45:18,720 --> 00:45:22,400
And if there is a force that is
pulling it down, could it be that

479
00:45:22,400 --> 00:45:27,600
same force is holding the moon
in its rotation around the Earth?

480
00:45:27,600 --> 00:45:31,800
And in that moment,
the theory of gravitation is born.

481
00:45:36,400 --> 00:45:39,720
Except the story's
almost certainly made up.

482
00:45:39,720 --> 00:45:45,000
Newton only started telling that
story when he was an old man,
and he possibly did it

483
00:45:45,000 --> 00:45:50,880
because he wanted to ensure that he
and he alone got full credit for
coming up with a theory of gravity.

484
00:45:50,880 --> 00:45:55,680
What is certain is that if he had
a moment of divine inspiration

485
00:45:55,680 --> 00:45:59,320
in this orchard, he did nothing
with it for nearly 20 years.

486
00:46:01,920 --> 00:46:08,120
It seems it was Halley's visit
that prompted Newton to really
develop his ideas.

487
00:46:08,120 --> 00:46:12,480
He would express his thinking
about gravity in a famous
thought experiment.

488
00:46:14,440 --> 00:46:19,520
He imagined a cannon on top
of a high mountain.

489
00:46:19,520 --> 00:46:26,720
He thought, if the ball leaves
a cannon slowly,
gravity would pull it to Earth.

490
00:46:26,720 --> 00:46:29,800
If the ball is fired too quickly,

491
00:46:29,800 --> 00:46:31,720
it would disappear into space.

492
00:46:31,720 --> 00:46:35,200
But if the speed is just right,

493
00:46:35,200 --> 00:46:41,240
then the force of gravity
would hold the ball in orbit
round the Earth, just like the moon.

494
00:46:41,240 --> 00:46:45,200
An orbit that follows
a simple mathematical law.

495
00:46:49,720 --> 00:46:57,120
His monumental work, explaining that
gravity held the universe together,
was published in 1687.

496
00:46:57,120 --> 00:47:03,520
This is Principia by Newton,
and it is beautiful.

497
00:47:03,520 --> 00:47:07,040
I have never held this book before,
and I can feel

498
00:47:07,040 --> 00:47:12,240
a little shiver going up my spine,
because this is the book

499
00:47:12,240 --> 00:47:19,800
which really did transform the world
and in fact would go on to dominate
science for the next 200 years.

500
00:47:28,000 --> 00:47:31,800
This was when the new vision of
the universe truly came together,

501
00:47:31,800 --> 00:47:36,400
built on Tycho's observations,

502
00:47:38,400 --> 00:47:40,560
Kepler's elliptical orbits,

503
00:47:42,760 --> 00:47:45,440
and Galileo's discoveries.

504
00:47:49,680 --> 00:47:55,720
Now Newton outlined
universal laws of motion that
explained how the planets moved.

505
00:48:02,480 --> 00:48:07,400
Newton was clearly
a scientific giant, but he was
also much more than that.

506
00:48:07,400 --> 00:48:13,160
The way that he had shown that a few
universal laws could explain so much
of the physical world inspired other

507
00:48:13,160 --> 00:48:19,200
intellectuals to look for universal
laws that could explain human
behaviour, politics, even history.

508
00:48:22,640 --> 00:48:28,720
Newton became a hero to
revolutionaries who dreamt of
utopian societies founded on reason.

509
00:48:32,840 --> 00:48:37,120
In America, politicians
were inspired by Newton's laws
of action and reaction

510
00:48:37,120 --> 00:48:41,120
when they created their
famous political system
of checks and balances.

511
00:48:44,360 --> 00:48:49,160
And in religion, an ordered universe
was taken to demonstrate

512
00:48:49,160 --> 00:48:52,520
the existence of a God
of infinite power.

513
00:49:00,040 --> 00:49:02,000
And astronomy?

514
00:49:05,120 --> 00:49:11,360
There was now a new stable model of
the universe, a clockwork universe,

515
00:49:11,360 --> 00:49:14,280
governed by a few simple laws.

516
00:49:19,680 --> 00:49:23,120
And that's how things stayed
for the next 200 years.

517
00:49:30,840 --> 00:49:36,160
The question of what is out there
has always followed the money.

518
00:49:36,160 --> 00:49:40,320
And in the early 20th century,
it headed across the Atlantic

519
00:49:40,320 --> 00:49:44,680
to California, where they were
enjoying an oil rush.

520
00:49:46,720 --> 00:49:51,000
Oil and railway barons, like
Renaissance princes before them,

521
00:49:51,000 --> 00:49:54,560
craved the sort of fame
that astronomy could bring.

522
00:49:59,080 --> 00:50:01,840
One philanthropist,
who had made his money building

523
00:50:01,840 --> 00:50:08,520
pipelines and selling hardware,
helped finance the next radical
shift in our view of the cosmos.

524
00:50:10,360 --> 00:50:15,880
John D Hooker was persuaded
to donate 45,000 towards building

525
00:50:15,880 --> 00:50:18,800
the largest telescope
the world had ever seen.

526
00:50:18,800 --> 00:50:23,800
And they dragged it up Mount Wilson,
this mountain, which is just
outside Los Angeles.

527
00:50:30,520 --> 00:50:33,640
It is a fantastic structure.

528
00:50:33,640 --> 00:50:40,280
'A hundred tons of pipework,
hardware and glass floats on
a bed of mercury,

529
00:50:40,280 --> 00:50:43,960
'allowing it to compensate
for the Earth's rotation.'

530
00:50:53,040 --> 00:50:55,560
Isn't that magnificent?

531
00:50:55,560 --> 00:50:58,360
Over 90 years old
and still fully operational.

532
00:51:01,720 --> 00:51:05,880
But for this gargantuan telescope
to fulfil its true potential,

533
00:51:05,880 --> 00:51:09,320
it would need a character
who was also larger than life.

534
00:51:13,320 --> 00:51:17,440
Edwin Hubble was an exceptionally
colourful scientist.

535
00:51:23,760 --> 00:51:25,880
After a spell at Oxford University,

536
00:51:25,880 --> 00:51:28,640
he came home with
a faux upper-class accent,

537
00:51:28,640 --> 00:51:32,920
and worked in jodhpurs
and high-topped riding boots.

538
00:51:34,440 --> 00:51:39,600
He was also exceptionally fortunate
to be hired to work with
the new Hooker telescope.

539
00:51:43,120 --> 00:51:48,080
Now, Hubble was a brilliant
astronomer, and he had the world's
largest telescope.

540
00:51:48,080 --> 00:51:52,480
Now the thing is, even with a
telescope this big, the human eye
is just not good enough

541
00:51:52,480 --> 00:51:55,200
to pick out the detail
that was needed.

542
00:51:58,360 --> 00:52:01,800
So there was a camera attached
to the telescope.

543
00:52:03,920 --> 00:52:09,840
And with it, Hubble photographed
stars at the far reaches
of the Milky Way,

544
00:52:09,840 --> 00:52:13,880
at that time, the only known galaxy
in the universe.

545
00:52:16,120 --> 00:52:20,000
On the 6th October 1923,
Hubble took a photograph

546
00:52:20,000 --> 00:52:23,800
that must rank as one of the most
significant photographs ever taken.

547
00:52:26,280 --> 00:52:32,280
This photograph demonstrated
for the first time just how vast
the universe truly is.

548
00:52:43,040 --> 00:52:48,800
Now, what you can see here is
a black, swirly area, which is
actually the Andromeda nebula.

549
00:52:48,800 --> 00:52:52,400
But what got Hubble excited
was a little black speck here,

550
00:52:52,400 --> 00:52:55,840
which he's labelled
as VAR, or variable star.

551
00:52:59,760 --> 00:53:02,240
This was a huge discovery.

552
00:53:05,560 --> 00:53:11,440
The pulsing of a variable star
could be used to calculate
its distance from Earth.

553
00:53:11,440 --> 00:53:15,880
Hubble came to
a startling conclusion.

554
00:53:15,880 --> 00:53:21,800
His star, and the nebula
in which it sat, were almost
a million light years away,

555
00:53:21,800 --> 00:53:24,480
far further than had been
thought possible.

556
00:53:26,000 --> 00:53:32,800
Now, Hubble realised that he could
prove for the first time that
the nebula was actually a galaxy,

557
00:53:32,800 --> 00:53:36,080
and it sat way outside
our own galaxy.

558
00:53:38,520 --> 00:53:46,160
Suddenly, the human race,
our world, our concerns, became
cosmically insignificant.

559
00:53:49,880 --> 00:53:56,880
We are just one small planet
in a vast galaxy, that sits amongst
billions of other galaxies.

560
00:54:01,240 --> 00:54:04,680
The implications of what
they had found were disturbing.

561
00:54:04,680 --> 00:54:08,360
The universe was vast,
possibly limitless.

562
00:54:08,360 --> 00:54:12,360
But what they did next
was even more shocking.

563
00:54:12,360 --> 00:54:17,800
They linked this giant telescope up
with a device called a spectrograph,

564
00:54:17,800 --> 00:54:21,120
and they pointed it once more
at the skies.

565
00:54:21,120 --> 00:54:26,680
They were hunting for objects which
they now believed to be galaxies,
and using the spectrograph,

566
00:54:26,680 --> 00:54:31,440
they measured the speed at which
those galaxies were either coming
towards or away from us.

567
00:54:37,400 --> 00:54:40,960
What they found was
the vast majority of these galaxies

568
00:54:40,960 --> 00:54:47,960
were actually receding, and some at
quite astonishing speeds of well
over a million miles an hour.

569
00:54:50,160 --> 00:54:56,200
Now, the implication of this was
obvious, the universe is expanding.

570
00:54:56,200 --> 00:55:00,400
Now, this really blew out of
the water the old way of thinking.

571
00:55:00,400 --> 00:55:05,960
Gone forever was the old static,
stable, Newtonian clockwork model.

572
00:55:05,960 --> 00:55:12,160
It seems, now,
we are actually living through
a giant cosmic explosion.

573
00:55:12,160 --> 00:55:16,280
It seems our universe
had a beginning.

574
00:55:21,440 --> 00:55:23,360
13 billion years ago.

575
00:55:25,480 --> 00:55:28,040
This became known as the Big Bang.

576
00:55:30,120 --> 00:55:34,960
Edwin Hubble never felt he achieved
the recognition he craved

577
00:55:34,960 --> 00:55:39,240
for his discovery of
the vastness of the cosmos.

578
00:55:39,240 --> 00:55:45,600
But floating high above the Earth
is the ultimate tribute
to this eccentric astronomer.

579
00:55:47,120 --> 00:55:49,480
The Hubble space telescope.

580
00:55:51,080 --> 00:55:54,600
400 years since Galileo ground
his first lenses,

581
00:55:54,600 --> 00:55:58,160
this is what we use
to look at what's out there.

582
00:56:01,600 --> 00:56:09,240
It can peer billions of light years
across the universe, back in time
towards the birth of everything.

583
00:56:16,640 --> 00:56:22,920
Our journey to find out what's
out there has been shaped by
powerful forces and beliefs.

584
00:56:22,920 --> 00:56:26,360
The Greek obsession
with divine circles.

585
00:56:26,360 --> 00:56:29,720
The courts of the Renaissance.

586
00:56:29,720 --> 00:56:31,840
By religious upheaval.

587
00:56:33,560 --> 00:56:37,320
Above all,
by the marriage of two skills -

588
00:56:37,320 --> 00:56:40,920
the making of instruments
and the generating of ideas.

589
00:56:40,920 --> 00:56:44,760
And it's still going on,

590
00:56:44,760 --> 00:56:50,720
as we find new ways of looking
ever deeper into our universe.

591
00:56:54,600 --> 00:56:56,680
So, what is out there?

592
00:56:56,680 --> 00:56:59,000
Well, rather a lot.

593
00:57:02,000 --> 00:57:06,880
We've seen the birth of stars,
in nurseries of gas and dust.

594
00:57:09,160 --> 00:57:13,760
Evidence of super massive
black holes.

595
00:57:13,760 --> 00:57:19,320
Clues to dark energy that may
make up most of our universe.

596
00:57:29,840 --> 00:57:34,440
Some of these ideas are as strange
and unsettling to us

597
00:57:34,440 --> 00:57:39,360
as the Earth going round the sun
was to contemporaries of Galileo.

598
00:57:40,920 --> 00:57:47,200
But I think what this journey really
boils down to is trust in evidence.

599
00:57:48,960 --> 00:57:52,640
'Because no matter how strange
the conclusions may seem,

600
00:57:52,640 --> 00:57:56,400
'it's only by accepting evidence
that we have come to understand

601
00:57:56,400 --> 00:58:01,760
'not just the universe,
but also our place here within it.'

602
00:58:06,040 --> 00:58:09,240
Isaac Newton, in a moment
of uncharacteristic modesty,

603
00:58:09,240 --> 00:58:15,040
once said that he was just a child
playing on the shores of a vast
ocean of undiscovered truths.

604
00:58:15,040 --> 00:58:19,000
But I think the contribution he and
his fellow stargazers really made

605
00:58:19,000 --> 00:58:25,240
was to open up our minds to what
is going on, not just up in
the heavens, but down here on Earth.

606
00:58:34,080 --> 00:58:39,480
'Next time - delving deep
to find beauty and order.

607
00:58:39,480 --> 00:58:43,000
'What is the world made of?'

608
00:59:00,000 --> 00:59:03,040
Subtitles by Red Bee Media Ltd

609
00:59:03,040 --> 00:59:06,080
E-mail - subtitling@bbc.co.uk