NARRATOR: Our closest
neighbor, mysterious as it is, tied to
our very survival, it's luminance has captivated
us since the beginning of humanity. But a closer look reveals
an ever-present source of myth, controversy, and
mystery, an unseen force that pulls at the earth every
second of the day, a source of illusion and wonder,
a celestial body so close to home that it may
impact the way we behave and the way our body functions. And without it, some
argue the planet Earth as we know it may
never have evolved. [theme music] Almost 240,000 miles
from Earth, our moon outshines every other celestial
body in the night sky. ROB ROY BRITT: The moon, when
it's up and when it's bright, makes us dream and wonder. NARRATOR: Our enigmatic
neighbor is also the source of countless unsolved
mysteries and age-old myths. NEIL F. COMINS The
moon is a spooky place. It's a mysterious place,
from the human perspective. The moon is a beautiful and
a really obvious thing to see. It's hard to miss, that big,
shining moon in the sky. So I think all
people from all times have had some need to understand
it, some need to relate to it. NARRATOR: Science may cast an
empirical light on some things about the universe,
but lunar experts are the first to admit they
don't have all the answers when it comes to our moon. Science is about process. We're never sure
about explanations. We know so little about
the moon because we've only been observing it close up
for a few hundred years, and it's been there for over
4 and 1/2 billion years. NARRATOR: Our moon teamed
with volcanic activity three to four billion years ago. Today, most believe it's an
inactive, dead world floating through space. But is it? July 20, 1969, Neil Armstrong
took his historic, small step during that first visit
to a lunar surface. NEIL ARMSTRONG: It's one small
step for man, one giant leap for mankind. NARRATOR: While on
the moon, Armstrong reported seeing what he called
an area that is considerably more illuminated than
the surrounding area, and that the area seems to have
a slight amount of fluorescence to it. What could it mean? Today, almost 40
years later, no one knows exactly what
that light source was. But scientists have witnessed
similar occurrences. There've been a whole class
of changes on the moon that had involved brightenings,
color changes, and even gaseous emissions. NARRATOR: These events have
left some, like NASA astronomer Bonnie Buratti, perplexed by
what they call Lunar Transient Phenomena, or LTPs. Lunar Transient Phenomena
are controversial. Scientists are very
skeptical about them. The problem is there's no
observations true and firm on these events. NARRATOR: But ever
since the Middle Ages, lunar observers have reported
seeing these mysterious lights. They're usually witnessed in the
dark, shadowy areas of the moon where the contrast is greater. They last anywhere from a
few seconds to a few hours. And that's why they've
been so hard to confirm. NARRATOR: Convinced that
these ethereal displays are a real phenomenon, but unsure
as to what's causing them, experts have honed in on
several possible explanations. There have been a number of
theories that have surfaced for Lunar Transient Phenomena. NARRATOR: Ever-changing
views from Earth may be causing the
appearance of bright flashes or surface changes on the moon. Some of the events
that I've seen are clearly just due to
turbulence in the earth's atmosphere. These cause movement
and change on the moon. NARRATOR: But Buratti
thinks that not all LTPs can be explained by
atmospheric turbulence. The anomalies that
Neil Armstrong reported were seen from
the lunar surface, so atmospheric turbulence
couldn't be causing them. Many astronomers, like
Laura Danly of the Griffith Observatory, believe that the
high-velocity impact of meteors and asteroids accounts for much
of this activity being observed from Earth They're traveling
very fast, so when they smash into
the moon, there's a big, bright explosion, really. NARRATOR: These impact
explosions, known as fireballs, may be one source
of the activity, but that premise has
a gaping hole in it. BONNIE BURATTI: Even though
we've seen these flashes on the dark side of the moon,
we haven't identified a crater associated with any of them. And that's where we get
into the controversy. There hasn't been any
large event that has been unequivocally observed. NARRATOR: Another
possible explanation is that when a
meteor hits the moon, it creates a massive crater. Landslides around the
crater rim kick up mountains of lunar dust. The fine dust could absorb
and scatter light rays or make it appear as if the moon
has somehow changed its surface features. It's possible that if a
landslide occurred on the moon, you would see something
from the earth, the edge of a crater
being obscured, a cloud-like feature forming. In other words, we would see a
crater wall, an LTP, and then a collapsed crater wall. We've never seen that yet. NARRATOR: Perhaps the
most controversial theory behind these lunar
anomalies could alter our view of the moon entirely. It would challenge the
belief that the moon has been geologically
inactive for millennia. BONNIE BURATTI: One of the
most intriguing explanations for Lunar Transient Phenomena
is active volcanoes on the moon. This is the most
scientifically important because it would tell us that
the moon is still geologically active. NARRATOR: Photographs taken
during the Apollo space missions revealed a rocky
formation on the lunar surface called the Ina structure. With this data, scientists
speculated that the moon could have experienced volcanic
activity in the last million years. The information
was groundbreaking, and it meant that
volcanic activity could be the primary source of LTPs. But most scientists are
yet to be convinced. BONNIE BURATTI: The
thing about science is whenever you have
a theory or a model, you have to be able to get
data of an event over and over again. In terms of these more
mysterious brightening or things that could
be volcanic events, we've never actually had
two independent observers obtain incontrovertible
data at the same time. NARRATOR: Even if the moon
isn't geologically active, some astronomers
believe there may be gases leftover from a time
when the volcanic activity was prevalent. If residual gases
reach the surface, the sun's rays would
scatter colored hues of red and blue from
the gas particles. BONNIE BURATTI: The moon could
still be experiencing out gassing without having actual
activity in the interior. There are minerals in the
moon that produce gases, and they seep up to the surface
in the moon and come out. NARRATOR: With so many
Lunar Transient Phenomena theories out there, which
is the most plausible? Dr. Buratti doesn't point to one
explanation for the phenomenon. I think the reasons for
LTP are probably myriad. I think there's more
than one explanation. It's not just one phenomenon. It's many different
types of activities. NARRATOR: For now, the cause
of the elusive Lunar Transient Phenomena may remain hidden
on the dark side of the moon. But the cause of full
moon fever here on Earth may be even tougher to diagnose. What role, if any,
does the full moon have on our bodies
and our minds? When it comes to exploring
the mysteries of the moon, perhaps the most celebrated
and controversial is whether our satellite has any
influence on the mind and body. We know that there's some
relationship between the earth and the moon, and so it's
perhaps not such a great leap to imagine that the different
changes, the full moon, might have some
influence on people. There are lots and
lots of mysteries, physical and psychological. [howl] One of the words
for madness, lunacy, comes from the Latin
word for moon, luna. So I think throughout history
people have associated the moon with human psychology. ROB ROY BRITT: A
lot of people really believe that the full moon
affects their behavior, affects maybe their biochemistry
or something like that. There is a widely held
belief among many people, including clinicians,
that during a full moon, there are changes,
palpable changes, in emergency room visits,
in pregnancy rates, in birth rates. There is a mythology
about behavior which changes consistently
with the phases of the moon. NARRATOR: Anecdotal evidence
abounds, but does science support the belief that a full
moon has a measurable effect on the earth's occupants? People have long tried
to associate the moon and the gravitational
effects of the moon with behavior in
people and animals. NARRATOR: Fact, the moon stirs
up the oceans, which make up 70% of our planet. So if the human body is
made up of 70% water, wouldn't that mean the
moon has just as much pull on human beings? Some respected members
of the medical community have reported changes in
human behavior and physiology during full moons. PETER PRESSMAN: We
must be open minded and, as careful
observers, continue to posit some relationship
between changes in the lunar cycle and the way
in which we behave, the way in which our health
and disease patterns move ahead through time. Then we probably need
to ask in creative, and critical, and rigorous
fashion the question, is this possible? NARRATOR: There are
some in law enforcement who believe that crime rates
increase when the moon is full. But others manning the
front lines aren't so sure. The way I see it personally,
I see it as a myth. NARRATOR: At the start
of a full moon shift, Deputy Jose Castro with the West
Hollywood Sheriff's Department scoffed at the idea that a lunar
pull has any effect on people. But in his first
20 minutes on duty, three calls had already come in. Right now, we're responding
to a 488, which is a theft that had just occurred. The call indicates that a male
Hispanic, approximately 32 years of age, wearing in an
orange jail jumpsuit, no pants, wearing blue underwear,
stole a book. Right now, we are responding
to a call of a 270-35, which is a domestic violence
now that is happening. This is the first domestic
violence we've had in a while, and it just so happens
there is a full moon. Right now, we're in
route a certain celebrity that lives within our area. The call states that a neighbor
at this celebrity's residence is throwing bottles at
the informants front yard. NARRATOR: By the end
of his busiest Tuesday night of the year, Deputy
Castro's skepticism was beginning to wane. I'll tell you what, at
the beginning of the shift, I wasn't a big believer, but
I'm becoming a believer now. A lot of this is
tied to the idea that the moon causes
tides on Earth, so maybe it causes
tides within people, but that just can't happen. The moon does not have a
tidal effect on our bodies. My chest doesn't get bigger
because the moon's pulling on it. NARRATOR: Dr. Peter Pressman, a
medical doctor at Cedars-Sinai Hospital in Los
Angeles, acknowledged that some of his peers believe
that the moon influences human behavior. Physicians who believe that
the moon does affect our bodies and our behavior come to
that conclusion on the basis of their observations. Those observations
may be very skewed. They may be very
situational, and they may not mean a thing, except that that's
what somebody has observed. NARRATOR: But Pressman
suspects the claims may contain a bias that's based on
personal experiences. PETER PRESSMAN: If you
look at the evidence, you find that there really
is no clear mechanism for the influence of the
moon with health and disease in human beings. Nevertheless, there continue
to be astute clinicians and careful observers who insist
that they do see relationships. LAURA DANLY: People's behavior
is driven by what they believe. And if you believe there
is something magical about the moon and it holds
a spell over you, then perhaps you will
change your behavior. NARRATOR: Whether the full
moon has any measurable impact on body and mind will continue
to be a source of debate and part of the
mythology of our moon. And there are other mythological
legends surrounding our closest neighbor. Even then, not everyone can
see the man in the moon. The man on the moon are
these giant, dark areas that create what some people
think looks like eyeballs, and a nose, and a smiley face. Let me begin by
saying that I have never seen the man on the moon. And how anyone can
see it is a matter of subjective creativity. NARRATOR: The moon has long been
the object of lore and myth, but what we think we see is
all in the eye of the beholder. Most cultures actually
don't see a man in. The rabbit is a big
favorite among many, and there are others. NARRATOR: But everyone
who looks up at the moon can see light and dark
areas on the lunar surface. And these are not an
illusion, but very real mountains and valleys. The light areas are
rugged, cratered highlands known as terrae,
Latin for lands. The highlands are part of
the moon's original crust that was shattered by the
impact of meteoroid, asteroids, and comets. The darker areas on the
moon are known as maria. Mari is a word meaning sea. They are ancient lava beds
that were at one time flowing but are now solid. NARRATOR: Formed from impact
cratering over billions of years, the maria account
for 16% of the moon's surface and look like bodies of water. ROB ROY BRITT: The
latest thinking is that giant asteroids hit
the other side of the moon and rocked the moon so
significantly that lava oozed out of the side that
we see and created these big, dark expanses of
lava that of course solidified over time. NARRATOR: The ancient
volcanic activity that formed the contrasts
of dark and light have inadvertently created
what some see as the features of a human face. The eyeballs are actually the
Mare Imbrium, Sea of Rains, and the Mare Serenitatis,
which means Sea of Serenity. The nose is the Sinus Aestuum,
which means Bay of Billows. And the open mouth is the Mare
Nubium, the Sea of Clouds, and the Mare Cognitum,
or Sea of Knowledge. For humans to see
a man on the moon, it may be our way of trying to
understand the lunar mystery and how we're inextricably
connected to it. Many mysteries of the moon have
influenced our civilization in dramatic ways. Ancient man based his calendar,
agriculture, mathematics, and astronomy on the changing
but consistent phases of the moon. Every month, the moon
appears to change its shape during an eight-phase
spin cycle. Why does the moon have phases? NEIL F. COMINS: The
phases of the moon occur because as the moon
orbits around the earth, we see more or less
of its lit side. NARRATOR: The light we see
being reflected from the moon is actually coming from the sun. Imagine the sun is over
there, and this is the earth, and this is the moon. When the moon is
fully lit by the sun, and we can see that lit
side, it's a full moon. As the moon goes
around the earth, we see less and
less of the lit side and more and more
of the dark side. NARRATOR: The full moon
occurs when the moon is on the opposite side of
the earth from the sun and the lunar surface
facing us is fully lit. NEIL F. COMINS: The shapes
and the phases of the moon are due to our perspective
on Earth, seeing more or less of the lit side of the moon. It's not a case of,
for example, the earth blocking some of the light that
would have otherwise struck the moon. That does occur, however,
during an eclipse. NARRATOR: And that terrestrial
perspective can sometimes play tricks on us. When it comes to the moon's
size, looks can be deceiving. Some of the moon's mysteries
are difficult to comprehend when our eyes tell us one
thing and science another. We just need a different
perspective on the problem. Sometimes when the full
moon rises in the sky, it appears much larger
near the horizon than it does when it's
positioned higher in the sky. Some observers judge the moon
to be as much as 50% to 75% larger when it first appears. But is the full
moon really larger when it's near the horizon? My friends all think
that the moon is bigger when it's on the horizon. I think that the moon is bigger
when it's on the horizon. NARRATOR: So what
could be causing it to look so different? The moon doesn't really
change its apparent size from the horizon to
overhead, but our perception is that it's larger. NARRATOR: One theory is that
our mind judges the moon's size in relation to other objects. It looks much
larger at the horizon because there are things
we can compare it to. Whereas at the top of
the sky, it's out there by it's little, old self. NARRATOR: In other words,
if we see a large object, such as a house,
dwarfed by the moon, our mind tells us that
the moon must be enormous. But when the moon
is out by itself, our mind doesn't
make that assumption. We see the moon as small. Another possible cause of
this is the Ponzo Illusion, named after Mario Ponzo, who
suggested that the mind judges the size of an object
based on its background. Ponzo drew two identical bars
across a picture of railroad tracks as they recede
in the distance. The upper bars look
wider because they appear to span the rails compared
to the lower bars, which fits between the rails. But in fact, the lines
overlaid on the tracks are the same size at both ends. Go out and take a pencil. And when the moon's rising, put
the pencil out at arm's length and see how big the
moon is compared to the eraser on the pencil. And then go out a couple hours
later and do the same thing when the moon is
higher in the sky, and you'll see that
the moon is exactly the same size in relation to
the pencil eraser at both times. NARRATOR: The moon may play
tricks with us when it comes to judging its size, but
there's nothing imaginary about its effects on our earth. Of all the hidden
lunar mysteries, there's one that can be
observed right here on Earth. It may be the most
influential phenomena that can be attributed to the moon. LAURA DANLY: From
our place on Earth, tides just appear to
be the times of day when the sea rises and falls. But that's an interaction,
a gravitational interaction, between the moon and the earth. So when the moon is passing
by, it pulls on the oceans and pulls it up higher, and
we see it as a high tide. NARRATOR: The ocean
tides are caused by the gravitational pull
of the sun and our moon. LAURA DANLY: The sun and the
moon both pull on the earth and contribute to tides,
but the moon is much closer, so it's pull of gravity is felt
more strongly than the sun's. NARRATOR: Oceanographer
Tetjana Ross says the moon's constant tug
on the earth is formidable. The reason that
the moon's influence is so visible in the form of
tides is because water can run. It can move. It's malleable. NARRATOR: In a
remote bay in Canada, one community has
learned to live with mysterious and extreme
ocean tides that are found nowhere else on Earth. While normal tides rise by
an average of three feet, the waters along
the Bay of Fundy, between Nova Scotia and New
Brunswick, swell up to 50 feet twice every day. One of the reasons the Bay
of Fundy has such large tides is because of the shape of the
land form underneath the bay. It's kind of a funnel shaped. And so as the water level
rises, it really rises rapidly. NARRATOR: At high tide
100 billion tons of water sloshes into the bay
in a matter of hours. Then during low tide, most of
it drains out like a bathtub. The base is shaped just so
so that the first tide comes in like a wave, and it moves
along, reflects off the back, and it comes out to the
mouth just at the same time as the next tide has built up. And so they add up in a
thing called resonance. Tidal resonances, just getting
the rise of the high tides to coincide, certain wavelengths
are reflected in a way that they reinforce each
other and amplify each other, and the tide is
therefore amplified. NARRATOR: The unique funnel
shape of the Bay of Fundy contributes to this resonance
and the height of its tides. The bay gradually splits into
a series of basins and river junctions that
restricts the tidal flow and contributes to the
extraordinary tides. Tides, one more way our planet
is forever tied to the moon, but it doesn't end there. We know that the moon's gravity
is constantly pulling up on the earth's oceans while
the earth's gravity pulls down on the moon. Everything in space is
tugging on everything else. So the earth is
tugging on the moon, and the moon is
tugging on the earth. NARRATOR: The moon's
gravitational pull on our oceans is so powerful
that it creates what's called a tidal bulge on
both sides of the planet. The moon pulls on the
earth gravitationally, and when it does
so, it also pulls on the oceans that are stretched
up a little bit toward it. It pulls preferentially on
the front side of the earth, pushes and pulls
the ocean toward it, then pulls the earth
a little bit less. And then the backside, the
ocean is not pulled quite as far toward the moon. So that's why there are
two bulges there called tidal bulges on the earth. NARRATOR: Tidal bulges
on our vast oceans actually impact the
earth's rotation. This tidal bulge that's
created by the moon, it's moving out ahead of
the moon a little bit. And the moon is actually pulling
back on this tidal bulge. Now when the moon pulls
back on this tidal bulge, that slows the earth down. NARRATOR: Without our moon, the
earth would spin much faster, and our days would
be much shorter. And this would affect how life
has evolved on this planet. But these tidal forces, which
tie the earth to the moon, travel a two-way street. Our earth also has an
undeniable effect on the moon. So if the moon had water
on it, would the earth's gravitational pull cause
similar tides on lunar oceans? The answer is yes. In fact, billions of years ago,
the moon was almost entirely made up of liquid-- but not water. When the moon was first
formed and very young, it was entirely
liquid rock, magma. The moon would have been like
a blazing inferno in the sky. And because the rock was
liquid, even though it was rock, the gravitational pull of the
earth and the orbit of the moon caused the liquid rock
to have tides, just like the water on
the earth today. NARRATOR: Over time, the
moon and its lava tides cooled into a solid,
desolate landscape, but the gravitational
relationship between the earth and the moon has never ceased. But imagine if there
was no moon making an appearance each night, how
different a world would it be? We are always tied to
this mysterious orb we call the moon, but what would
have happened to Earth if there were no moon? The fact that we
exist today is, in part, due to the moon
allowing the earth to create the environment,
the early oceans, all the minerals that
allow us to exist. If there had
never been a moon, Earth would be a different place
today because the moon creates tides on Earth that
shape our shorelines and reshape the landscape. NARRATOR: Here's how the
moon impacted our evolution. About 4 and 1/2 billion years
ago, the gravitational forces between the moon and
Earth were much stronger. When the moon was formed,
it was much, much closer to us than it is today. It took only five hours
for it to orbit the earth, and it was huge in the sky
because it was so much closer. NARRATOR: And more
gravity exerted onto the earth
from a closer moon meant the world to
our fate as a species. When oceans first washed our
planet under a closer moon, the tides were a thousand times
greater than they are today. You could imagine that instead
of having a 10-foot tide like we have today, you'd
have a 10,000-foot tide, so you would have 10,000-foot
tides rushing inland. NARRATOR: These
intense tides helped create the right conditions in
the oceans for life to develop. NEIL F. COMINS: Tides ripped the
outer layers of the crust off of the earth and put
them into the ocean. And that mineral-rich
soup, the primordial soup, was capable of developing
and evolving life. NARRATOR: And some scientists
believe that tidal pools would have been an ideal setting
for life to evolve and adapt to a terrestrial environment. It would've been a
great place, for example, for the first creatures from
the sea to get their legs. They could have come into
a tidal pool where it's wet half the day and
dry half the day, and it would've been a great
place to grow your legs and eventually move on to land. NARRATOR: According to
astronomer Neil Comins, we can't underestimate
the moon's influence on our development as a species. Without the moon, I don't
think that that process would have occurred nearly as quickly. We've evolved so that our
biological clocks are based on around 23, 24-hour time. If the moon had never
existed, the day would be six-hours long. And we, as the creatures we
are today, couldn't exist. NARRATOR: As the moon
slowed Earth's orbit, it stabilized our rotation and
affected our climate and ocean tides. And the moon greatly
influenced the development of mammals so dependent
on moonlit nights for their survival. Has the moon had a major
impact on our existence? I think absolutely. NARRATOR: Every time
the moon is full, the lunar image is
exactly the same. There's a puzzling
mystery to this. It makes many
wonder why we never see another side of the moon. ROB ROY BRITT: After 4.5
billion years of evolving the, Earth-Moon system has arrived
at a point where the moon shows us the same face all the time. NARRATOR: Billions of years
ago, the friction created by volcanic tides caused the
moon to slow its rotation and become tidally
locked to Earth. This doesn't mean our
moon isn't spinning, but it has slowed
down considerably over billions of years. And the secret of the
moon's hidden far side has to do with synchronicity. If this is the earth, and if
this is the side of the moon that we see, if the moon were
not rotating, then eventually, we would see the other
side of the moon. Because the moon is
rotating at the same rate that it orbits the earth,
synchronous rotation, we always see the same side. The far side of the
moon is not always dark. If you were out in
space, you would be able to see that the sun
hits all sides of the moon as the moon makes its month-long
orbit around the earth. But from where we sit,
we can only see one side. NARRATOR: Gravity
is in firm control of the Earth-Moon relationship. Or is it? The gravity that has held
the moon in our orbit is slowly losing its grip,
and the consequences of that are enough to make one look at
the moon in a whole new light. BONNIE BURATTI: Gravity is
a force that holds the moon to the earth, just as this
athlete is bound to the hammer that is orbiting about
his body, so gravity binds the moon and the earth. If gravity all of
a sudden went away, the moon would fly off into
space, just as this hammer flies off over the field. NARRATOR: Of course,
gravity never stops working, but could the moon somehow
slip loose of its grip? The truth is the moon has
always been slowly slipping away from us. The moon has been moving away,
and it's still moving away. In fact, the moon
moves away from us a couple of inches every year. And eventually, the moon's going
to be so far away that it won't even seem like our moon anymore. NARRATOR: Ever since the moon
and Earth became intertwined, the energy from the
earth's gravitational tug has been causing the moon to
spiral away from our planet. It's currently moving away
from us at a rate of one to two inches each year. The key to this
unexpected effect are the tidal bulges created
on the earth by the moon. LAURA DANLY: The tides
on earth actually act to propel the moon outward,
spiraling out further from the earth every orbit. The reason is because the earth
spins faster than the moon orbits us, so after the moon
has pulled up a tidal bulge, raised the high tide, the earth
turns and pulls slightly ahead of it. So there's just a little
bit of a forward force, or we call it a torque, a
little bit of an extra kick that speeds it up
ever so slightly. But over time, that speeding up
makes it go faster and faster, which, in orbit, means it's
going spiraling further and further away. NARRATOR: Over time the
moon will expand its orbit until someday, it will finally
be beyond our earth's gravity. But scientists say there's
no cause for panic. Quite a bit of time will
pass before the moon is out of sight and out of orbit. Estimated time of total
departure, about 50 billion years, and our
sun will flame out in less than 10 billion years. Throughout history, the moon
has delighted, surprised, and sometimes terrified us,
and the movement of our Earth may be the cause
of this mystery. Another secret of the moon has
been documented in ancient text and continues to amaze. It usually appears
every few years. During a total lunar eclipse,
the full moon dramatically changes colors. What causes this? A lunar eclipse
is very simple. It just occurs
when the earth gets between the sun and the moon. So when Earth gets
in the way, Earth casts a giant shadow that blocks
the sunlight from reaching the moon. NARRATOR: At the
peak of this eclipse, the moon passes completely
into Earth's shadow, or umbra, and transforms not to
black, as one might expect, but to a blood red. What happens is some of the
sunlight that's being blocked by the earth actually slips
through the atmosphere, and the red light
gets through the best. As the sun's rays pass
through the earth's atmosphere, they're bent a little
bit, and the red rays are bent in such a
way that they make it over the surface of the earth
and illuminate the moon. NARRATOR: And when only red or
orange light reaches the lunar surface, the moon appears red,
another optical phenomenon that adds to the moon's mystique. And part of that mystique
can be attributed to the dramatic presence
of the moon above us. It outshines every other
celestial body in the night sky. NEIL F. COMINS:
There's a special magic to the moon, its
changing phases, its brightness in the
otherwise dark sky. NARRATOR: But we also see
the moon during the daytime. Why is this? It's actually very easy
to understand why we can see the moon during the daylight. You can do this
demonstration at home. All you need is a bright light
to act as the sun and a piece of fruit to act as the moon. My face is acting as the earth. The lit-up side is the daylight
side, and the part in shadow is the nighttime side. Now the moon, of course,
orbits the earth. And at some of the times
during the month in its orbit, it's on the daylight
side of the moon, so I'm able to see
it in full daylight. NARRATOR: Actually, many planets
and stars are just above us during the daytime, but
the light from the sun is just so bright that it
obscures nearly all of them. Only the moon, which is 100,000
times brighter than the nearest star, shines through. We don't always see
the moon during the day because it's constantly
moving around our earth, and it's not in
the same position at the same time every day. But somewhere on the
planet, it's always visible. But as we've learned, not
everything about the moon is easy to explain
or understand. There are still plenty of
questions left unanswered. It's been part of
the moon's mystique since history was
first recorded. We are forever tied
to our neighbor, but we know so little
about that dependence. There could be other things
that are happening that we just don't know about yet. Over the next
century or so, I think that science is going to take
us further into understanding its mysteries. Whether we will fully
understand it, I doubt it. LAURA DANLY: I certainly don't
think we know everything there is to know about the moon. There is a tremendous
amount to learn. But fortunately,
it's within reach, and we will go
exploring it further and learn a lot more about it. NARRATOR: Until we rekindle our
efforts to explore the lunar world more thoroughly, we may
never know all the secrets or hope to solve the hidden
mysteries of the moon.
