Humanity began in Africa. But we didn’t stay there, not all of us—over thousands of years our ancestors walked all over the continent, then out of it. And when they came to the sea, they built boats and sailed tremendous distances to islands they could not have known were there. Why?
Probably for the same reason we look up at the moon and the stars and say, “What’s up there? Could we go there? Maybe we could go there.” Because it’s something human beings do.
Space is, of course, infinitely more hostile to human life than the surface of the sea; escaping Earth’s gravity entails a good deal more work and expense than shoving off from the shore. But those boats were the cutting-edge technology of their time. Voyagers carefully planned their expensive, dangerous journeys, and many of them died trying to find out what was beyond the horizon. So why keep doing it?
I could tell you about spin-off technologies, ranging from small products of convenience to discoveries that might feed millions or prevent deadly accidents or save the lives of the sick and injured.
I could tell you that we shouldn’t keep all our eggs in this increasingly fragile basket—one good meteor strike and we all join the non-avian dinosaurs. And have you noticed the weather lately?
I could tell you that it might be good for us to unite behind a project that doesn’t involve killing one another, that does involve understanding our home planet and the ways we survive on it and what things are crucial to our continuing to survive on it.
I could tell you that moving farther out into the solar system might be a good plan, if humanity is lucky enough to survive the next 5.5 billion years and the sun expands enough to fry the Earth.
I could tell you all those things: all the reasons we should find some way to live away from this planet, to build space stations and moon bases and cities on Mars and habitats on the moons of Jupiter. All the reasons we should, if we manage that, look out at the stars beyond our sun and say, “Could we go there? Maybe we could go there.”
It’s a huge, dangerous, maybe impossible project. But that’s never stopped humans from bloody-mindedly trying anyway.
Humanity was born on Earth. Are we going to stay here? I suspect—I hope—the answer is no. —Ann Leckie
Ann Leckie is the Hugo- and Nebula-award-winning author ofAncillary Justice.
Gravity’s a Drag
Getting off Earth is a little like getting divorced: You want to do it quickly, with as little baggage as possible. But powerful forces conspire against you—specifically, gravity. If an object on Earth’s surface wants to fly free, it needs to shoot up and out at speeds exceeding 25,000 mph.
That takes serious oomph—read: dollars. It cost nearly $200 million just to launch the Mars Curiosity rover, about a tenth of the mission’s budget, and any crewed mission would be weighed down by the stuff needed to sustain life. Composite materials like exotic-metal alloys and fibered sheets could reduce the weight; combine that with more efficient, more powerful fuel mixtures and you get a bigger bang for your booster.
But the ultimate money saver will be reusability. “As the number of flights increases, economies of scale kick in,” says Les Johnson, a technical assistant at NASA’s Advanced Concepts Office. “That’s the key to getting the cost to drop dramatically.” SpaceX’s Falcon 9, for example, was designed to relaunch time and again. The more you go to space, the cheaper it gets. —Nick Stockton
Our Ships Are Way Too Slow
Hurtling through space is easy. It’s a vacuum, after all; nothing to slow you down. But getting started? That’s a bear. The larger an object’s mass, the more force it takes to move it—and rockets are kind of massive. Chemical propellants are great for an initial push, but your precious kerosene will burn up in a matter of minutes. After that, expect to reach the moons of Jupiter in, oh, five to seven years. That’s a heck of a lot of in-flight movies. Propulsion needs a radical new method. Here’s a look at what rocket scientists now have, or are working on, or wish they had. —Nick Stockton
problem: space junk
It’s a Minefield Up There
Congratulations! You’ve successfully launched a rocket into orbit. But before you break into outer space, a rogue bit of broke-ass satellite comes from out of nowhere and caps your second-stage fuel tank. No more rocket.
This is the problem of space debris, and it’s very real. The US Space Surveillance Network has eyes on 17,000 objects—each at least the size of a softball—hurtling around Earth at speeds of more than 17,500 mph; if you count pieces under 10 centimeters, it’s closer to 500,000 objects. Launch adapters, lens covers, even a fleck of paint can punch a crater in critical systems.
Whipple shields—layers of metal and Kevlar—can protect against the bitsy pieces, but nothing can save you from a whole satellite. Some 4,000 orbit Earth, most dead in the air. Mission control avoids dangerous paths, but tracking isn’t perfect.
Pulling the sats out of orbit isn’t realistic—it would take a whole mission to capture just one. So starting now, all satellites will have to fall out of orbit on their own. They’ll jettison extra fuel, then use rocket boosters or solar sails to angle down and burn up on reentry. Put decommissioning programs in 90 percent of new launches or you’ll get the Kessler syndrome: One collision leads to more collisions until there’s so much crap up there, no one can fly at all. That might be a century hence—or a lot sooner if space war breaks out. If someone (like China?) starts blowing up enemy satellites, “it would be a disaster,” says Holger Krag, head of the Space Debris Office at the European Space Agency. Essential to the future of space travel: world peace. —Jason Kehe
There’s No GPS for Space
The Deep Space Network, a collection of antenna arrays in California, Australia, and Spain, is the only navigation tool for space. Everything from student-project satellites to the New Horizons probe meandering through the Kuiper Belt depends on it to stay oriented. An ultraprecise atomic clock on Earth times how long it takes for a signal to get from the network to a spacecraft and back, and navigators use that to determine the craft’s position.
But as more and more missions take flight, the network is getting congested. The switchboard is often busy. So in the near term, NASA is working to lighten the load. Atomic clocks on the crafts themselves will cut transmission time in half, allowing distance calculations with a single downlink. And higher-bandwidth lasers will handle big data packages, like photos or video messages.
The farther rockets go from Earth, however, the less reliable this method becomes. Sure, radio waves travel at light speed, but transmissions to deep space still take hours. And the stars can tell you where to go, but they’re too distant to tell you where you are. For future missions, deep-space navigation expert Joseph Guinn wants to design an autonomous system that would collect images of targets and nearby objects and use their relative location to triangulate a spaceship’s coordinates—no ground control required. “It’ll be like GPS on Earth,” Guinn says. “You put a GPS receiver on your car and problem solved.” He calls it a deep-space positioning system—DPS for short. —Katie M. Palmer
Space Turns You Into a Bag of Cancer
Outside the safe cocoon of Earth’s atmosphere and magnetic field, subatomic particles zip around at close to the speed of light. This is space radiation, and it’s deadly. Aside from cancer, it can also cause cataracts and possibly Alzheimer’s.
When these particles knock into the atoms of aluminum that make up a spacecraft hull, their nuclei blow up, emitting yet more superfast particles called secondary radiation. “You’re actually making the problem worse,” says Nasser Barghouty, a physicist at NASA’s Marshall Space Flight Center.
A better solution? One word: plastics. They’re light and strong, and they’re full of hydrogen atoms, whose small nuclei don’t produce much secondary radiation. NASA is testing plastics that can mitigate radiation in spaceships or space suits.
Or how about this word: magnets. Scientists on the Space Radiation Superconducting Shield project are working on a magnesium diboride superconductor that would deflect charged particles away from a ship. It works at –263 degrees Celsius, which is balmy for superconductors, but it helps that space is already so damn cold. —Sarah Zhang
problem: food and water
Mars Has No Supermarkets
Lettuce got to be a hero last August. That’s when astronauts on the ISS ate a few leaves they’d grown in space for the first time. But large-scale gardening in zero g is tricky. Water wants to float around in bubbles instead of trickling through soil, so engineers have devised ceramic tubes that wick it down to the plants’ roots. “It’s like a Chia pet,” says Raymond Wheeler, a botanist at Kennedy Space Center. Also, existing vehicles are cramped. Some veggies are already pretty space-efficient (ha!), but scientists are working on a genetically modified dwarf plum tree that’s just 2 feet tall. Proteins, fats, and carbs could come from a more diverse harvest—like potatoes and peanuts.
All that’s for naught, though, if you run out of water. (On the ISS, the pee-and-water recycling system needs periodic fixing, and interplanetary crews won’t be able to rely on a resupply of new parts.) GMOs could help here too. Michael Flynn, an engineer at NASA Ames Research Center, is working on a water filter made of genetically modified bacteria. He likens it to how your small intestine recycles what you drink. “Basically you are a water recycling system,” he says. “with a useful life of 75 or 80 years.” This filter would continually replenish itself, just like your innards do. —Sarah Zhang
problem: bone and muscle wasting
Zero Gravity Will Transform You into Mush
Weightlessness wrecks the body: It makes certain immune cells unable to do their jobs, and red blood cells explode. It gives you kidney stones and makes your heart lazy. Astronauts on the ISS exercise to combat muscle wasting and bone loss, but they still lose bone mass in space, and those zero-g spin cycles don’t help the other problems. Artificial gravity would fix all that.
In his lab at MIT, former astronaut Laurence Young is testing a human centrifuge: Victims lie on their side on a platform and pedal a stationary wheel as the whole contraption spins around. The resulting force tugs their feet—just like gravity, but awkward.
Young’s machine is too cramped to use for more than an hour or two a day, though, so for 24/7 gravity, the whole spacecraft will have to become a centrifuge. A spinning spaceship could be shaped like a dumbbell, with two chambers connected by a truss. As it gets easier to send more mass into space, designers could become more ambitious—but they don’t have to reinvent the wheel. Remember the station in 2001: A Space Odyssey? The design has been around since 1903. —Sarah Zhang
problem: mental health
Interplanetary Voyages Are a Direct Flight to Space Madness
When physicians treat stroke or heart attack, they sometimes bring the patient’s temperature way down, slowing their metabolism to reduce the damage from lack of oxygen. It’s a trick that might work for astronauts too. Which is good, because to sign up for interplanetary travel is to sign up for a year (at least) of living in a cramped spacecraft with bad food and zero privacy—a recipe for space madness. That’s why John Bradford says we should sleep through it. President of the engineering firm SpaceWorks and coauthor of a report for NASA on long missions, Bradford says cold storage would be a twofer: It cuts down on the amount of food, water, and air a crew would need and keeps them sane. “If we’re going to become a multiplanet species,” he says, “we’ll need a capability like human stasis.” Sleep tight, voyagers. —Sarah Zhang
Crashing Is Not an Option
Planet, ho! You’ve been in space for months. Years, maybe. Now a formerly distant world is finally filling up your viewport. All you have to do is land. But you’re careening through frictionless space at, oh, call it 200,000 mph (assuming you’ve cracked fusion). Oh yeah, and there’s the planet’s gravity to worry about. If you don’t want your touchdown to be remembered as one small leap for a human and one giant splat for humankind, follow these simple steps. —Nick Stockton
You Can’t Take a Mountain of Aluminum Ore With You
When space caravans embark from Earth, they’ll leave full of supplies. But you can’t take everything with you. Seeds, oxygen generators, maybe a few machines for building infrastructure. But settlers will have to harvest or make everything else.
Luckily, space is far from barren. “Every planet has every chemical element in it,” says Ian Crawford, a planetary scientist at Birbeck, University of London, though concentrations differ. The moon has lots of aluminum. Mars has silica and iron oxide. Nearby asteroids are a great source of carbon and platinum ores—and water, once pioneers figure out how to mine the stuff. If blasters and drillers are too heavy to ship, they’ll have to extract those riches with gentler techniques: melting, magnets, or metal-digesting microbes. And NASA is looking into a process that can 3-D-print whole buildings—no need to import special equipment.
In the end, a destination’s resources will shape settlements, which makes surveying the drop zone critical. Just think of the moon’s far side. “It’s been pummeled by asteroids for billions of years,” says Anita Gale, a space shuttle engineer. “Whole new materials could be out there.” Before humanity books a one-way ticket to Kepler-438b, it’ll have to study up. —Chelsea Leu
We Can’t Do Everything By Ourselves
Dogs helped humans colonize Earth, but they’d survive on Mars about as well as we would. To spread out on a new world, we’ll need a new best friend: a robot.
See, settling takes a lot of grunt work, and robots can dig all day without having to eat or breathe. Theoretically, at least. Current prototypes— bulky, bipedal bots that mimic human physiognomy—can barely walk on Earth. So automatons will have to be everything we aren’t—like, say, a lightweight tracked bot with backhoe claws for arms. That’s the shape of one NASA machine designed to dig for ice on Mars: Its two appendages spin in opposite directions, keeping it from flipping over as it works.
Still, humans have a big leg up when it comes to fingers. If a job requires dexterity and precision, you want people doing it—provided they have the right duds. Today’s space suit is designed for weightlessness, not hiking on exoplanets. NASA’s prototype Z-2 model has flexible joints and a helmet that gives a clear view of whatever delicate wiring needs fixing. When the job’s done, just hop on an autonomous transporter to get home. Attaboy, Rover. —Matt Simon
problem: space is big
Warp Drives Don’t Exist … Yet
The fastest thing humans have ever built is a probe called Helios 2. It’s dead now, but if sound traveled in space, you’d hear it screaming as it whips around the sun at speeds of more than 157,000 miles per hour. That’s almost 100 times faster than a bullet, but even at that velocity it would take some 19,000 years to reach Earth’s first stellar neighbor, Alpha Centauri. It’d be a multigenerational ship, and nobody dreams of going to space because it’s a nice place to die of old age.
Advocates of space exploration often get asked the question: “Why should we spend money on NASA where there are so many problems here on Earth?” Universe Today has been compiling a list of responses to this question by space-bloggers from across the web. Check it out, there are some great answers.
In response to Universe Today’s call for answers, we decided to compile a list of our top reasons that space exploration is a worthwhile endeavor. I also encourage everyone to read The Case for Space Exploration, a collection of essays and articles put together by the Space Foundation.
Now, without further ado, our list:
1. Perspective – As our telescopes probe the depths of space and time and our spacecraft missions reveal the scale and diversity of worlds even within our own solar system, we are provided with a humbling sense of our place in the universe. Carl Sagan expressed the significance of this perspective in a beautiful passage in his book Pale Blue Dot. You can also listen to Sagan himself read the passage in this video clip. The world would be a better place if everyone watched that video.
2. Protecting and Understanding our World –
3. Inspiration – The Apollo missions inspired an entire generation of students to pursue math and science careers. As our society becomes more technology-dependent, the populace needs to become scientifically literate to keep up. Telling students that “You could be the first astronaut on Mars!” or “You could be the one driving the next Mars rovers!” is a pretty effective way of inspiring them to study science and math.
4. The Economy – NASA does not launch buckets of cash into space. The majority of the money spent on space exploration goes toward the salaries of thousands of skilled American workers who make NASA’s missions so successful. For more on this, and its connection to the recent Mars rover budget scare, check this post.
5. Exploration – To be human is to be an explorer. It is part of who we are: since the first tribes left the African savanna and spread into Europe and Asia, we have had the need to explore the unknown. Now humans have visited or settled every corner of the globe. The instinct to explore is still active, but there are very few outlets. Some people seek out extreme or exotic places to satisfy this need, risking their lives to do so. Others look to the skies. It may be an old cliche, but Star Trek had it right: Space is the final frontier, and it calls to the explorer in all of us.
6. New Technology – Space exploration brings together a lot of smart people from many different fields and puts them to work on some very difficult problems. The result is not only fantastic scientific discoveries, but also many useful inventions. From healthier baby food to technology to better diagnose breast cancer, to farther flying golf balls, NASA technology is all around you. Check here for an extensive list.
7. Answering The Big Questions – How did life begin?How did the universe begin?How was our world created?Are we alone? These questions and others have been asked by every generation since the dawn of time. That we can even ask them is a testament to the power of the human brain. Now, because we are smart enough and bold enough to explore the universe, we are finding the answers. In the words of Carl Sagan, “We are starstuff contemplating the stars.”
8. International Collaboration – Large space exploration projects are almost always the result of international cooperation. The International Space Station is the most obvious example, but the space shuttle regularly has astronauts from other nations, and many robotic missions include instruments built by teams in other countries. As NASA gears up to return to the moon, precursor missions from Japan, India, China and Russia are already in orbit, are planned, or are under construction. Future human Mars missions will almost certainly involve multiple space agencies to spread the cost among several nations.
9. Long-term Survival – As it stands, all of humanity’s eggs are in one small basket called “Earth”. It is only a matter of time before something happens to our planet that is so devastating that it changes the course of life as we know it. Whether the disaster is natural, like a rogue comet, or self-inflicted, like nuclear war, it is possible that our home will no longer be habitable. What happens, then, to all of the accomplishments of the last thousand generations of humans? All of our art, our music, our literature, our science, even our very genes could be wiped out. Unless, of course, there are a few humans living elsewhere in the solar system. Space exploration and colonization of the Moon and Mars are an insurance policy for humanity and all of our achievements.
That’s what we came up with. We think that, based on the reasons above, it is certainly worth it to spend 0.60% of the national budget (just six out of every thousand dollars) on NASA. We’re interested to hear what you think. Is the investment in NASA worth it?
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