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Dark Futures: Does Humanity Really Need a Backup Earth?
By Elizabeth Howell, Space.com Contributor | May 21, 2018 06:00am ET
0 0 MORE
Dark Futures: Does Humanity Really Need a Backup Earth?
If things went south on Earth, could Mars or an exoplanet be Earth 2.0?
Credit: T. Pyle/NASA/JPL-Caltech
SpaceX CEO Elon Musk has a vision: He wants to get humans to Mars as
soon as possible. He already wowed the world this year, when the Falcon
Heavy launched and flung a Tesla car toward the asteroid belt. And this
heavy-lift rocket will be dwarfed by the boosters Musk plans for Mars
exploration, which he says will carry colonists in fleets of ships to
the Red Planet.
While getting to Mars is an end in itself, there's another compelling
reason to go. Science fiction is full of dystopian futures for Earth if
humanity remains limited to this planet. There are the asteroid strikes
of the "Deep Impact" and "Armageddon" films, the robot wars of the
"Battlestar Galactica" TV series and "Terminator" film franchise, the
medical problems and overpopulation in the "Children of Men" and
"Elysium" movies, and many other disasters natural and artificial. Dark
futures and colonizing other planets will be covered in "AMC
Visionaries: James Cameron's Story of Science Fiction," which runs its
fourth episode tonight (May 21).
Science fiction inspired the first rocket pioneers to explore beyond
Earth. Robert Goddard, who pushed forward liquid rocketry in the early
1900s, was clearly a fan of the genre, because he wrote some science
fiction himself, according to io9. The Apollo moon rockets of the 1960s
and 1970s were designed by Wernher von Braun, who enjoyed science
fiction as a child and partnered with Disney in the 1950s to create
educational films about spaceflight. [Gallery: Visions of Interstellar
Starship Travel]
Advertisement
And a quick glance around the solar system shows us one real-life reason
scientists — and indeed, all of us — should take a page from science
fiction and be concerned about Earth's future. The moon, Mars and many
of the "airless" moons around the neighborhood are littered with
craters. These came from space rocks and other small worlds that slammed
into the moon's and planet's surfaces over billions of years.
Lest you imagine that Earth is immune because of its thick atmosphere,
think of the dinosaurs, felled about 66 million years ago when a large
asteroid or comet around 10 to 15 kilometers (6.2 to 9.3 miles) in
diameter slammed into the Earth. We also just passed the five-year
anniversary of Chelyabinsk, when a 17-meter (56 feet) small body
exploded over a town in Russia, causing many injuries and property
damage from shattered glass.
NASA does have an active asteroid-search program and some plans for
dealing with asteroids menacing Earth, but even preparing for those
intruders isn't enough; there's another, bigger inevitable threat to our
planet. In about 4 billion years or 5 billion years, the sun will swell
into a red giant after it consumes all of its hydrogen and begins fusing
helium. As the star expands, it will swallow up Mercury and Venus and
get close to Earth. Our planet will be roasted to a crisp, thrown out of
its orbit or swallowed altogether. In any of these scenarios, that's bad
news for humans and life on Earth in general.
Legendary director James Cameron talks the dark futures of science
fiction with director Christopher Nolan in the fourth episode of AMC
Visionaries: James Cameron's Story of Science Fiction, which airs May
21, 2019.
Legendary director James Cameron talks the dark futures of science
fiction with director Christopher Nolan in the fourth episode of AMC
Visionaries: James Cameron's Story of Science Fiction, which airs May
21, 2019.
Credit: AMC
Get your a— to Mars
One popular destination for escaping Earth in science fiction is Mars.
At first, this was because people thought other beings like us may live
there. In 1877, Italian astronomer Giovanni Schiaparelli reported
observing channels on Mars, but stopped short of saying whether they
were natural or artificial. U.S. science popularizer Percival Lowell,
however, went much further in the early 1900s, coming up with
explanations as to why the channels were there. Perhaps the Martians
were trying to drain water to support a dying planet, Lowell said. (The
channels, or canals, were later explained as telescope artifacts when
robotic missions to Mars showed the formations don't exist.)
This turn-of-the-century musing greatly influenced science fiction of
the era. There was the famous "War of the Worlds" novel by H.G. Wells in
1898, which portrayed a Martian invasion of Earth. (It was recapped in a
1938 national radio broadcast, as well as a 2005 film starring Tom
Cruise.) Also, Edgar Rice Burroughs published "A Princess of Mars" in
1912, kicking off a series about Mars (which he called Barsoom) full of
living beings. (The widely panned 2012 movie "John Carter" was based on
some of these stories.) [Film Review: 'War of the Worlds' Update Hits Home]
Robert Zubrin, founder of the human exploration advocacy group The Mars
Society, told Space.com that Mars will someday be an inhabited planet as
science fiction writers envisioned. As only two examples of many showing
that future, there's the 2015 Matt Damon movie "The Martian" or the 1990
Arnold Schwarzenegger film "Total Recall," which included the famous
line, "Get your a— to Mars."
But why does science fiction make exploration look so much easier than
we find in real life? Zubrin said, in part, it's because of our mindset.
"Here we are, 500 years or so after [Nicolaus] Copernicus [who said
Earth orbits the sun], and most people still talk about the Earth as the
world, and there's a thing above us called the sky. Most people still
have this geocentric viewpoint," Zubrin told Space.com, pointing out
that Earth is in space and we rarely think about that fact in our
everyday lives.
Zubrin said our approach of going to Mars via low Earth orbit and the
moon is incremental. This approach to space exploration, he said, is
similar to telling Lewis and Clark to just go 100 miles (160 kilometers)
out beyond the Mississippi River and to wait for the next group of
explorers to move farther west.
"If someone asks you why space is so important, it's comparative to
somebody in a small village somewhere saying, 'Why is the rest of the
world important?' which is sort of an absurd question," Zubrin said. So,
he advocates going elsewhere in search of resources, knowledge or a safe
haven that we couldn't find on Earth. Interstellar travel would be the
ultimate dream, Zubrin said, but in the meantime, we should focus on
what we have at hand: Mars, which is close enough to visit using today's
technology.
"The most important step is deciding that you want to do it. This is
really the dramatic step that Elon Musk is taking," Zubrin said. "There
are people at NASA who want to do it, but as an institution, it has been
dragging its feet and providing every excuse to the political class not
to embrace the challenge."
Moving to Mars — or beyond?
Zubrin's plan (which he outlined in a 1991 paper called "Mars Direct,"
and which he has expanded on greatly since then) advocates for a direct
flight to Mars, with minimal or no on-orbit assembly of the spacecraft.
Using current propulsion systems, a spacecraft could get to the Red
Planet in six months — the standard rotation astronauts spend on the
International Space Station, Zubrin pointed out.
The first missions would bring most of the supplies those travelers
would need to live, such as food and water. But the early trips could
also bring along architecture so later missions could do more "living
off the land," such as greenhouses or habitats. (The first Mars voyagers
may eat more meat brought with them, while future generations would be
more vegetarian due to the resources on hand, Zubrin said.) He said the
habitats of the Mars Society's Mars Desert Research Station and
Flashline Mars Arctic Research Station are designed to preview what real
Red Planet homes could look like.
The return vehicle would include propellant made from Martian carbon
dioxide and water, specifically to generate the fuels methane and
oxygen. Zubrin said it's the cheapest propellant combination, with only
a hydrogen-oxygen mix providing better exhaust velocity.
But there's a big problem with Mars — it's not very much like Earth.
Sure, people could conceivable live on it with technology to manage the
risks. Its day is similar in length to Earth's day, too. But the planet
has only one-third of Earth's gravity. Martian air isn't breathable.
Water, if it exists at all on the surface, would be in scarce
quantities. Conditions are even worse on the moon, which has one-sixth
Earth's gravity, a longer day-night cycle than our home planet and no
air whatsoever.
"They're not places that we are necessarily going to colonize in large
numbers," Roger Launius, a retired curator from the Smithsonian
Institution's National Air and Space Museum, told Space.com. He
predicted that by the end of the century, there may be research stations
at the moon or Mars, similar to what exists now in Antarctica.
But to really find another home for humanity, we'll have to follow the
lead of "Battlestar Galactica" and search for another Earth. Because,
otherwise, children are going to be born in lunar or Martian
environments that have a lesser gravity than Earth. How this will affect
their development when humans are built for Earth is an unknown, Launius
said.
But quickly getting to other stars, where second Earths may exist, will
be slow unless we figure out a method for faster-than-light speed, or a
way to sustain a spacecraft over multiple generations, Launius said.
Another possibility is to extend astronaut life spans through
hibernation (as done in the movies "Alien" and "Avatar") or by becoming
a sort of "Star Trek"-like Borg that would integrate robotics into the
human body to extend lives.
This story was inspired by Episode 4 of "AMC Visionaries: James
Cameron's Story of Science Fiction," which airs tonight at 10 p.m.
EDT/PDT (9 p.m. CDT). A companion book is available on Amazon.com.
Follow us @Spacedotcom, Facebook and Google+. Original article on
Space.com.
https://www.space.com/40641-does-humanity-need-backup-earth.html
Dark Futures: Does Humanity Really Need a Backup Earth?
By Elizabeth Howell, Space.com Contributor | May 21, 2018 06:00am ET
0 0 MORE
Dark Futures: Does Humanity Really Need a Backup Earth?
If things went south on Earth, could Mars or an exoplanet be Earth 2.0?
Credit: T. Pyle/NASA/JPL-Caltech
SpaceX CEO Elon Musk has a vision: He wants to get humans to Mars as
soon as possible. He already wowed the world this year, when the Falcon
Heavy launched and flung a Tesla car toward the asteroid belt. And this
heavy-lift rocket will be dwarfed by the boosters Musk plans for Mars
exploration, which he says will carry colonists in fleets of ships to
the Red Planet.
While getting to Mars is an end in itself, there's another compelling
reason to go. Science fiction is full of dystopian futures for Earth if
humanity remains limited to this planet. There are the asteroid strikes
of the "Deep Impact" and "Armageddon" films, the robot wars of the
"Battlestar Galactica" TV series and "Terminator" film franchise, the
medical problems and overpopulation in the "Children of Men" and
"Elysium" movies, and many other disasters natural and artificial. Dark
futures and colonizing other planets will be covered in "AMC
Visionaries: James Cameron's Story of Science Fiction," which runs its
fourth episode tonight (May 21).
Science fiction inspired the first rocket pioneers to explore beyond
Earth. Robert Goddard, who pushed forward liquid rocketry in the early
1900s, was clearly a fan of the genre, because he wrote some science
fiction himself, according to io9. The Apollo moon rockets of the 1960s
and 1970s were designed by Wernher von Braun, who enjoyed science
fiction as a child and partnered with Disney in the 1950s to create
educational films about spaceflight. [Gallery: Visions of Interstellar
Starship Travel]
Advertisement
And a quick glance around the solar system shows us one real-life reason
scientists — and indeed, all of us — should take a page from science
fiction and be concerned about Earth's future. The moon, Mars and many
of the "airless" moons around the neighborhood are littered with
craters. These came from space rocks and other small worlds that slammed
into the moon's and planet's surfaces over billions of years.
Lest you imagine that Earth is immune because of its thick atmosphere,
think of the dinosaurs, felled about 66 million years ago when a large
asteroid or comet around 10 to 15 kilometers (6.2 to 9.3 miles) in
diameter slammed into the Earth. We also just passed the five-year
anniversary of Chelyabinsk, when a 17-meter (56 feet) small body
exploded over a town in Russia, causing many injuries and property
damage from shattered glass.
NASA does have an active asteroid-search program and some plans for
dealing with asteroids menacing Earth, but even preparing for those
intruders isn't enough; there's another, bigger inevitable threat to our
planet. In about 4 billion years or 5 billion years, the sun will swell
into a red giant after it consumes all of its hydrogen and begins fusing
helium. As the star expands, it will swallow up Mercury and Venus and
get close to Earth. Our planet will be roasted to a crisp, thrown out of
its orbit or swallowed altogether. In any of these scenarios, that's bad
news for humans and life on Earth in general.
Legendary director James Cameron talks the dark futures of science
fiction with director Christopher Nolan in the fourth episode of AMC
Visionaries: James Cameron's Story of Science Fiction, which airs May
21, 2019.
Legendary director James Cameron talks the dark futures of science
fiction with director Christopher Nolan in the fourth episode of AMC
Visionaries: James Cameron's Story of Science Fiction, which airs May
21, 2019.
Credit: AMC
Get your a— to Mars
One popular destination for escaping Earth in science fiction is Mars.
At first, this was because people thought other beings like us may live
there. In 1877, Italian astronomer Giovanni Schiaparelli reported
observing channels on Mars, but stopped short of saying whether they
were natural or artificial. U.S. science popularizer Percival Lowell,
however, went much further in the early 1900s, coming up with
explanations as to why the channels were there. Perhaps the Martians
were trying to drain water to support a dying planet, Lowell said. (The
channels, or canals, were later explained as telescope artifacts when
robotic missions to Mars showed the formations don't exist.)
This turn-of-the-century musing greatly influenced science fiction of
the era. There was the famous "War of the Worlds" novel by H.G. Wells in
1898, which portrayed a Martian invasion of Earth. (It was recapped in a
1938 national radio broadcast, as well as a 2005 film starring Tom
Cruise.) Also, Edgar Rice Burroughs published "A Princess of Mars" in
1912, kicking off a series about Mars (which he called Barsoom) full of
living beings. (The widely panned 2012 movie "John Carter" was based on
some of these stories.) [Film Review: 'War of the Worlds' Update Hits Home]
Robert Zubrin, founder of the human exploration advocacy group The Mars
Society, told Space.com that Mars will someday be an inhabited planet as
science fiction writers envisioned. As only two examples of many showing
that future, there's the 2015 Matt Damon movie "The Martian" or the 1990
Arnold Schwarzenegger film "Total Recall," which included the famous
line, "Get your a— to Mars."
But why does science fiction make exploration look so much easier than
we find in real life? Zubrin said, in part, it's because of our mindset.
"Here we are, 500 years or so after [Nicolaus] Copernicus [who said
Earth orbits the sun], and most people still talk about the Earth as the
world, and there's a thing above us called the sky. Most people still
have this geocentric viewpoint," Zubrin told Space.com, pointing out
that Earth is in space and we rarely think about that fact in our
everyday lives.
Zubrin said our approach of going to Mars via low Earth orbit and the
moon is incremental. This approach to space exploration, he said, is
similar to telling Lewis and Clark to just go 100 miles (160 kilometers)
out beyond the Mississippi River and to wait for the next group of
explorers to move farther west.
"If someone asks you why space is so important, it's comparative to
somebody in a small village somewhere saying, 'Why is the rest of the
world important?' which is sort of an absurd question," Zubrin said. So,
he advocates going elsewhere in search of resources, knowledge or a safe
haven that we couldn't find on Earth. Interstellar travel would be the
ultimate dream, Zubrin said, but in the meantime, we should focus on
what we have at hand: Mars, which is close enough to visit using today's
technology.
"The most important step is deciding that you want to do it. This is
really the dramatic step that Elon Musk is taking," Zubrin said. "There
are people at NASA who want to do it, but as an institution, it has been
dragging its feet and providing every excuse to the political class not
to embrace the challenge."
Moving to Mars — or beyond?
Zubrin's plan (which he outlined in a 1991 paper called "Mars Direct,"
and which he has expanded on greatly since then) advocates for a direct
flight to Mars, with minimal or no on-orbit assembly of the spacecraft.
Using current propulsion systems, a spacecraft could get to the Red
Planet in six months — the standard rotation astronauts spend on the
International Space Station, Zubrin pointed out.
The first missions would bring most of the supplies those travelers
would need to live, such as food and water. But the early trips could
also bring along architecture so later missions could do more "living
off the land," such as greenhouses or habitats. (The first Mars voyagers
may eat more meat brought with them, while future generations would be
more vegetarian due to the resources on hand, Zubrin said.) He said the
habitats of the Mars Society's Mars Desert Research Station and
Flashline Mars Arctic Research Station are designed to preview what real
Red Planet homes could look like.
The return vehicle would include propellant made from Martian carbon
dioxide and water, specifically to generate the fuels methane and
oxygen. Zubrin said it's the cheapest propellant combination, with only
a hydrogen-oxygen mix providing better exhaust velocity.
But there's a big problem with Mars — it's not very much like Earth.
Sure, people could conceivable live on it with technology to manage the
risks. Its day is similar in length to Earth's day, too. But the planet
has only one-third of Earth's gravity. Martian air isn't breathable.
Water, if it exists at all on the surface, would be in scarce
quantities. Conditions are even worse on the moon, which has one-sixth
Earth's gravity, a longer day-night cycle than our home planet and no
air whatsoever.
"They're not places that we are necessarily going to colonize in large
numbers," Roger Launius, a retired curator from the Smithsonian
Institution's National Air and Space Museum, told Space.com. He
predicted that by the end of the century, there may be research stations
at the moon or Mars, similar to what exists now in Antarctica.
But to really find another home for humanity, we'll have to follow the
lead of "Battlestar Galactica" and search for another Earth. Because,
otherwise, children are going to be born in lunar or Martian
environments that have a lesser gravity than Earth. How this will affect
their development when humans are built for Earth is an unknown, Launius
said.
But quickly getting to other stars, where second Earths may exist, will
be slow unless we figure out a method for faster-than-light speed, or a
way to sustain a spacecraft over multiple generations, Launius said.
Another possibility is to extend astronaut life spans through
hibernation (as done in the movies "Alien" and "Avatar") or by becoming
a sort of "Star Trek"-like Borg that would integrate robotics into the
human body to extend lives.
This story was inspired by Episode 4 of "AMC Visionaries: James
Cameron's Story of Science Fiction," which airs tonight at 10 p.m.
EDT/PDT (9 p.m. CDT). A companion book is available on Amazon.com.
Follow us @Spacedotcom, Facebook and Google+. Original article on
Space.com.