Minster design extreme weather
Alien landscapes and bizarre phenomena
Is the most complex system we know of in the universe
that planet
Is earth and we are only beginning to unlock its secrets
The planet Earth is a haven for life
Conditions are perfect. I mean, they really are perfect
oceans of liquid water make life possible
But that's not enough a
Complex secret gives earth its life
while hundreds of other known planets fall short
Not a single one of these planets look just like the earth
What makes Earth so perfect
Why does it depend on the moon?
volcanoes
even the planet Jupiter
What puts earth in the ultimate Goldilocks zone?
for life
May 19 2012
In the Arizona desert a 35 year old visitor from Germany is overcome by
105 degree temperatures
The first of two hikers to die this weekend from early season eat
Water makes up 60% of his human body
As little as 2 to 3% decrease in body water can unset the symptoms of dehydration
Humans on earth exists on a knife's edge between life and death
Surviving only in a narrow range of temperatures
So two in the solar system there is only a narrow range in which planets can support complex life
This place not too hot. Not too cold is called
the Goldilocks zone
Estimates put the Goldilocks zone between 67 million and
279 million miles from the Sun
And it's just right for the one thing life seems to need
liquid water
You're not so close that water boils away you're not so far away that water turns to ice perfect Goldilocks
We're in the cow who deserts on the Island of Hawaii
When you look at dry places like this, it really makes you appreciate how vital water is to animals and plants
Hawaii's Big Island is also home to rainforests
waterfalls
Seacoast and even snow-capped mountains where the secrets of life success on earth play out
Among those secrets a recipe for life that needs far more than just liquid water
One of the biggest surprises of the last 20 years
Is the large number of conditions the earth needs to maintain its state as being habitable
Besides Earth's distance from the Sun
life also depends on the planets volcanoes
Its large moon and even the planet Jupiter
Liquid water is important, but that's possible at a wide range of temperatures not all of them good for life
The highest temperature that complex life can live at is very very different from that of microbes
We animals really can't live much above 113 to 115 degrees Fahrenheit
The Na Hoku rainforest on Hawaii is a Goldilocks zone on a Goldilocks planet
There are more species packed around me right now than any other place I could go to
This rainforest and others like it represent the apex of species diversity on planet Earth
The diversity Springs from conditions that are not only wet
But also warm without being too hot
Life likes to be warm 70 to 80 to 90 degrees. That's ideal. That's where you want to be
The Earth's volcanoes hold the secret of the planetary thermostat
If it weren't for these mountains of fire this entire planet would freeze
Thank for watching !
January 3rd 1983
Hawaii's Kilauea volcano begins its longest eruption and recorded history as
lava flows through residential areas
The first homes destroyed there were 16 homes
shortly after that initial eruption a
Vivid reminder of the destructive power of the volcano
The volcano's fury fuels mankind's fear
But the erupting Mountains hold a secret
They are essential to life and play a central role in making Earth a Goldilocks planet
Volcanoes are commonplace in the solar system
They have erupted on Mars
on Jupiter's moon Io and
May number and the thousands of Venus
But unlike other planets Earth's volcanoes are coupled to plate tectonics
the planets method of resurfacing its crust
Earth is the only known planet whose crust actively moves around with many distinct plates
Many scientists now believe plate tectonics is the most important secret other than water in
Making earth just right for life
It all has to do with carbon dioxide
Right now it may be making the planet to war
But life actually needs some of that warming
Without co2 the earth would be very cold
It would be zero degrees Fahrenheit 32 degrees below freezing without that carbon dioxide the entire planet would be a frozen wasteland
The co2 emerges from Earth's volcanoes along with their destructive lava
The essential gas cycles both in and out of the atmosphere
Acting like a thermostat to keep the planet not too hot not too cold
It may be one of the best-kept secrets of Earth's existence a series of interconnected
Reactions that was the entire planet to work a chain of events in which one weak link
Would make life as we know it
impossible
Fiery volcanoes see you unlikely players in the drama that makes earth. So perfect for life
And yet without them the planet would be covered with ice and life would have little chance of success
The secret is in the carbon dioxide that volcanoes supply to the planet's atmosphere
The volcanic vent you see here is one of many in the Hawaiian Islands is from vents like these the carbon dioxide
Comes out of the deep earth and goes into the Earth's atmosphere
As a greenhouse gas co2 turns earth's temperature up
But in doing so it becomes the core component of the planetary thermostat
It is a delicate global balancing act
If the temperature is cool the planet makes carbon dioxide go up so the air gets warmer
If the air gets warmer, the planet makes carbon dioxide go down to turn things cooler
One way a hotter earth make co2 go down as by ramping up the chemical weathering of rocks
Carbon dioxide mixed with rainwater turns into a weak acid that eats away at births rocks
When temperatures go up the process naturally goes faster
The acid reactions absorb carbon dioxide and suck it out of the air
Earth's weathered rocks get help from another process to draw down carbon dioxide in the atmosphere
More heat also speeds up the growth of untold numbers of plants and animals in the ocean
Many of these draw carbon dioxide right out of the air and use it to make their shells
All of these shells slowly sink onto the sea bottom to produce a limestone layer on the sea floor
With both the formation of sea shells and the weathered rocks
carbon dioxide dips down in the atmosphere
Did it goes too far the planet could freeze
So it needs a way to make co2 go back up
That happens deep underwater
In the middle of the ocean massive ridges on the seabed erupt with lava as plate tectonics
drives the motion of the Earth's crust
Making the ocean floor spread apart
Miles away the spreading seafloor crashes into a continental plate
The sea plate dives down into the Earth's interior the limestone melts liberating its carbon dioxide
The carbon dioxide that was set free underground eventually comes out here back where we started at a volcanic vent
So now the earth becomes warmer and the cycle begins again
The finely tuned system has adjusted the atmosphere as carbon dioxide up and down to keep the Goldilocks zone on Earth
intact for billions of years
Plate tectonics
Also makes Earth's land surfaces move
The giant Pacific plate for instance slowly moves to the northwest and carries with it the Big Island of Hawaii. I
Like to think of the ground beneath my feet is stable, but geologically speaking
We're in constant motion right where I'm standing on the mountain of Kilauea. I'm moving 2 to 4 inches a year annually
North-northwest, so if you came back to see me next year I wouldn't be here
I'd be here
When continents move apart species are isolated and evolved into new ones
Life's wild variety grows
The complexity versus eight is an essential survival tool
Especially when earth comes under attack from outer space
The secret ingredients for thriving life abound on planet earth
But its wealth of rich climates is also home to environments on the edge of habitability
One of them is Mauna Kea an inactive volcano on the Big Island of Hawaii
It's an alien landscape home to a dozen giant telescopes
But at high altitude astronomers are working on the margins of the Goldilocks zone for humans
I've been up here at 13 and a half thousand feet many times and sometimes I feel a little bit of altitude sickness
My head isn't working right I feel nauseous
The oxygen content up here is only about 60% that of c-level
Astronomers here have discovered that the recipe for life success on earth
includes many ingredients
from space
The moon
Unusually large for a planet of Earth's size
Has a secret impact on life
It provides stability for Earth's axis of rotation
The pole of the moon's gravity keeps the earth from wobbling uncontrollably
Without our moon we'd be flopping around like a dead fish
This isn't stability life needs two things. It needs conditions to live, but it needs those conditions to exist
Over long periods of time you need conditions to remain very very stable
Having a large moon is part of the secret
The stability also comes from unlikely sources
Many people are astonished to learn that the planet Jupiter 500 million miles away
has a huge effect on life on Earth a
Major impact was a rare event on earth when an asteroid may have wiped out the dinosaurs 65 million years ago
It remains rare today because Jupiter acts as a cosmic vacuum cleaner as the planets overwhelming gravity
grabs comets and asteroids
Sweeping them out of the solar system
Jupiter in our lifetime swept the comet right out of existence shoemaker-levy 9
Went crashing into Jupiter
That particular comet was on an earth crossing orbit. Jupiter sucked it out of existence
If you do not have a gigantic Jupiter the solar system will be full of debris
That would hit the earth all the time. Meaning that life would be impossible
So thank you Jupiter for cleaning out the solar system
Earth's astronomers are now engaged in one of history's greatest quests the
Search for other planets suitable for life
In early 2013 they identified a possible planet more like Earth than any yet found
at
2070 light-years distant it is 1.5 times Earth's mass and orbits within its stars Goldilocks zone
there's thought to be about 50 billion planets in our Milky Way galaxy of which perhaps
500 million are in the habitable zone
But that's not enough
Mars for instance is in the habitable zone
But it's weak gravity and irregular magnetic field left it unable to hold on to most of its atmosphere
Future outgassing might reverse the process. But today it cannot support complex life
It also turns out that the Goldilocks zone for any such planet doesn't last forever
Even Earth's time as a just right planet may run out
sooner than you think
Planet Earth's secret set of special factors make it perfect for life
Most important its place around the Sun in the Goldilocks zone
A planet is set to be in the Goldilocks zone
When it's distanced from the star that it orbits leads to temperatures that allow liquid water
to exist on its surface
But the deepest secret of births goldilocks existence is not one of place and temperature
It is one of time
For complex life to evolve Goldilocks temperatures must remain stable for long periods
We have been in what we call the habitable zone now since the formation of life on Earth at least four billion years ago
and
That depends on the Sun that does not burn out quickly
If the Sun were a gigantic star it would burn his hydrogen very rapidly and only last for maybe a billion years or so
And that's too short to get life off the ground
But even a long-lived star like Earth's Sun changes over time and so does its Goldilocks zone
As our Sun bursts is fuel. In fact, it gives off more and more heat. It's actually going to expand
Although a hotter Sun could incinerate complex life
There's a secret killer that may strike millions perhaps a billion years sooner
Today carbon dioxide is temporarily on the rise making the earth too warm
But in the long term the mechanisms that take it out of the atmosphere will dominate making co2 gradually disappear
We can predict that perhaps it as little as a billion years from now
There will no longer be enough carbon dioxide for plants to undertake photosynthesis when that happens
We very rapidly lose oxygen in our atmosphere and when that happens that spells the end of all animals on planet Earth
But would the increased heat from the Sun result in new Goldilocks zone migrating into more distant parts of the solar system
They could be that Mars will become temporarily habitable
Or maybe one of the moons of Jupiter or Saturn that has an icy crust will have liquid water on its surface
Life's future will be at stake
While microbes may survive the extreme conditions on a superheated earth
Could its intelligent life-forms escape to seek refuge elsewhere?
If identical conditions aren't found will successor worlds be good enough
Can they evolve their own set of factors that have made the success of complex life one of the greatest?
secrets of the earth
You
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