by Buzz Aldrin
But operating at an asteroid is not a piece of cake. There are great lags in Earth-to-NEO communication times. This kind of deep space mission calls for true autonomy, as crew members are far from Earth, and their space travel must include a great deal of assurance in backup hardware, space propulsion, life-support gear, and radiation shielding. That being the case, a major report finding is that the body of data required to support flying astronauts outward to an NEO is severely limited.
Then there are the psychological and sociological issues linked with an NEO-bound crew cooped up and confined in tight quarters like those offered by an Orion spacecraft. The 2011 report underscores the fact that deep space missions do not afford the abort opportunities and the psychological comfort provided by rapid return to our home planet—a hallmark of my Apollo 11 mission and the six follow-on flights within cislunar space.
My concern here is that far more work is essential to support human expeditions outside of Earth’s protective magnetosphere. What still remains as a biological concern is the heightened and long-term physiological effects of space radiation on the human body.
There are arguably many “need-to-knows” about NEOs. That is, just how much data is requisite before a piloted mission departs Earth toward the target space rock? What about the object’s spin rate, size and shape, and makeup—solid rock or rubble pile? Also troubling is the ability to station-keep with an asteroid without placing crew and spacecraft in harm’s way. In this case, a mobile exploration module deployed from the main spacecraft could carry explorers and robotic tools over to the asteroid. That would seem like a wise and safe approach.
Visits by crews to even the largest asteroids must deal with lack of gravity to safely land. It’s more likely to be “docking” to the object in some manner. One idea, proposed by MIT researchers, is tying a lightweight network of tether material entirely around an asteroid. Once in place, astronauts could attach themselves to this set of connections and maneuver or perhaps even walk along the surface. Still, along with the low gravity, asteroids are surely going to be challenging destinations for human and robotic investigation due to the fine, granular topside material spread across the object’s surface.
There are ways to make practice runs at NEOs right here on Earth. One technique, which draws upon my early work in underwater simulation of spacewalking, is NASA’s Extreme Environment Mission Operations, or NEEMO for short. International crews of aquanauts are trying to understand what a mission to an asteroid would be like. Home base for these evaluations is the National Oceanic and Atmospheric Administration’s Aquarius Reef Base undersea research habitat off the coast of Key Largo, Florida, and some 60 feet below the surface of the Atlantic Ocean.
Underwater maneuvers replicate the challenge of asteroid exploration.
(Illustration Credit 5.11)
Part of the work is to develop tools and techniques for use on lower gravity environments of NEOs. Working on an asteroid presents special obstacles, say for snagging and bagging geologic samples. Again, great care must be taken as loose material can coast away; an astronaut can be propelled off an NEO’s surface just by striking a rock with a hammer.
Cosmic Shooting Gallery
Let’s face facts. We live in a cosmic shooting gallery. Ways to defend ourselves from NEOs need careful study. If there is adequate warning time, we have the means to guard Earth from asteroid impacts—a luxury that the dinosaurs were not afforded. But what deflection method to use is still to be determined. There are brute-force concepts, like using a nuclear bomb to blow an NEO to smithereens. Another less harsh option is the “gravity tractor”—a way to alter an NEO’s course with a slight nudge over time, using the gravity tug of a spacecraft that has sidled up near the object. Lasers or sunlight-focusing mirrors could also be used to heat up a spot on an asteroid, vaporizing surface material to create a propulsive force that alters the object’s path.
There’s even been talk of capturing and transporting a small asteroid to near-Earth orbit. A 500-ton asteroid could be fetched and then deposited into a gravitationally stable point in the sun-Earth or moon-Earth system. This NEO moving plan uses a container-like robotic spacecraft powered by a solar electric propulsion system. Once the asteroid is on location, it would be subject to human study, perhaps even a popular tourist stop, as well as exploited as a resource.
Outreach to the asteroids yields a number of benefits. Scientifically, we can find out more about the formation and history of our solar system. From a security standpoint, understanding the structure and composition of asteroids, and learning how to operate spacecraft around NEOs, empowers us to deflect a hazardous intruder from afar. Then there’s appraising the feasibility of utilizing asteroid resources for human expansion in space.
Now under way is development of a unique asteroid sample-return mission. This spacecraft is to speed toward 1999 RQ36, a space rock that has the highest Earth-impact probability in the next few centuries of any known asteroid.
NASA’s OSIRIS-REx mission is being led by the University of Arizona and is slated to launch in 2016, rendezvous with the asteroid in 2019–2021, then return specimens of the object to Earth in 2023.
OSIRIS-REx is an acronym drawn from the work of the mission: Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer. The mission will identify carbonaceous asteroid resources that can be used in human exploration. Another spacecraft duty is to take measurements to quantify the Yarkovsky effect—the daily heating of an object rotating in space can exert a small force on the object.
According to OSIRIS-REx researchers, when the heated surface of 1999 RQ36 points its hot afternoon side in the direction of its motion around the sun, the escaping radiation acts like a small rocket thruster. That propulsive push slows it down and sends it closer to the inner solar system. While that thrust is minuscule, a little push day after day, year after year, for hundreds of years, can alter an asteroid’s orbit significantly. More important, the Yarkovsky effect can turn an NEO headed for Earth into an impactor—or a clean miss.
The OSIRIS-REx mission is expected to provide important data, a tool to aid in securing Earth from future asteroid impacts. With time on our side, policymakers can settle on what—if any—steps should be taken to mitigate the odds of 1999 RQ36 banging into Earth.
Pay Dirt!
Extraterrestrial mining in the years to come is one way to spread Earth’s economic sphere of influence. Drawing upon the resources of the moon, Mars, asteroids, comets, and other bodies of the solar system can fuel the economic fires of an expanding, outbound civilization.
There are private efforts under way to scope out the job of quarrying space. While the business plans, dollars required, and the technology needed may be jelling, there are thorny questions ahead, issues that organizations are likely to bend their private-sector pick on: property and mineral rights, ownership and possession, international treaties.
The Space Resources Roundtable, often held at the Colorado School of Mines in Golden, Colorado, has increasingly become a hotbed of discussion on these topics. At a roundtable meeting last year, Jim Keravala, Chief Operating Officer of the Shackleton Energy Company, detailed a plan to “fuel the space frontier”—one that would traffic rocket fuel, oxygen, water, and other items into low Earth orbit and on the moon, making this service available to all spacefarers. A mix of industrial astronauts and robotic systems would service customers with a steady stream of propellants and other materials. The business plan calls for liberation of icy resources bound within permanently shadowed craters at the south pole of the moon, processing that material. The company wants to establish a network of refueling service stations in low Earth orbit and on the moon to process and churn out fuel and consumables for commercial and government customers.
But what’s ahead is the prospect of legal-beagle debate and court cases concerning mining claims, surface rights, even possession by a squatter. During the School of Mines roundtable, some voiced the point that po
ssession is nine-tenths of ownership. Even the view that it’s easier to receive forgiveness than obtain permission circulated among participants.
For a large mining group to get involved in exploiting space resources there must be surety they can make a profit, cautions Dale Boucher, Director of Innovation at the Northern Centre for Advanced Technology, Inc., in Sudbury, Ontario, Canada. He feels that governments should get together and create the regime in which space resource mining can take place.
Most certainly, there are legal matters to be resolved, and before too much is assumed. It’s my personal sense that the United Nations is not the body that should be determining the future legalities of space prospecting and mining. Rather, I see something like an International Orbital Development Authority, an International Lunar Development Authority, and an International Outer Orbit Authority handling these issues.
In the case of setting up the U.S. flag on the moon on Apollo 11, there wasn’t a “one small step … it’s mine” declaration. We set a precedent. We also noted the plaque mounted on the Eagle lander that read: “Here men from the planet Earth first set foot upon the moon July 1969, A.D. We came in peace for all mankind”—words used to convey that our mission was one of exploration and not conquest.
How sorting out the adjudication of resource-rich celestial objects will play out remains open for dialogue and, quite literally, there is need to dig into these issues deeper.
The outlook for mining asteroids was boosted in 2012 by the intentions of a new private U.S. company, Planetary Resources, Inc., based in Seattle. This team of entrepreneurs announced the venture aimed at mining the solar system, a plan that is billionaire-backed and enthusiastically supported by such people as filmmaker James Cameron, an adviser to the group.
Chris Lewicki, President and Chief Engineer of Planetary Resources, has scripted a multipronged program to access resources from near-Earth asteroids. He makes it clear that developing space resources and creating a market for the volatile mineral and metallic resources of asteroids would be a slice of a larger undertaking. Mining the moon, establishing space-based solar power, and growing a space tourism market are examples of taking the economic sphere of influence on Earth and moving it beyond the belt of moneymaking geostationary satellites, where it now abruptly stops.
Planetary Resources design for capture of near-Earth asteroid for mining
(Illustration Credit 5.12)
Planetary Resources has outlined a plan to launch a line of low-cost robotic spacecraft. In essence, they have a business plan that calls for the detection, inspection, and interception of asteroids. A first step is to explore for and chart resource-rich asteroids within reach. After intensive study of selected asteroids, the group’s intent is to then develop the most efficient capabilities to deliver asteroid resources directly to both space-based and terrestrial customers. What can be extracted from near-Earth asteroids?
Asteroids are floating troves of materials like iron, nickel, and water, as well as of rare platinum group metals—often in significantly higher concentration than found on Earth—such as ruthenium, rhodium, palladium, osmium, iridium, and platinum.
These space rocks vary widely in composition. They can contain water, metals, and carbonaceous materials in various amounts. Some asteroids are loaded with large quantities of water, while other asteroids hold concentrated metals rare on Earth. Water from asteroids is a key resource in space, not only as sustenance for human space travelers but also as rocket propellant.
Certainly not last on the benefit list is furthering American preeminence in space by conducting deep space missions that are practice runs for getting our feet firmly on Mars.
So in summary, prior to conducting either robotic or human missions, securing the target asteroid’s orbit and what it’s like is critical. For instance, how fast is the asteroid’s rotation period; how easy will it be to station-keep alongside the object or “dock” and anchor to the space rock’s surface? Surface activities at an asteroid include robotic sample collection and deployment of probes (radar, acoustic, seismometer, et cetera), experiments, and planetary defense devices.
What about the long-duration human interplanetary space mission itself and the unique challenges for the crew, spacecraft systems, and the mission control team back on Earth? Like in the reach for Mars, the drive outward to NEOs needs to utilize the International Space Station to assist in the development of technologies and operational approaches.
Needing emphasis here is that a human mission to an asteroid is a “short-stay” Mars moons mission. It demonstrates, among a list of purposes, linkage to future Mars missions in terms of exercising the transportation system, surveying planetary bodies, furthering deep space operations by crews, and performing teleoperations from a piloted spacecraft to the object being studied.
However the future unfolds, what’s needed is a series of steps that convert the NEO natural hazard into natural stepping-stones to support our jump deeper into space. Doing so fills the bill of my Unified Space Vision rules of the road, of exploration, science, development, commerce, and security—and keeps us solidly on the road ahead.
Buzz Aldrin shows a model of Phobos, one of Mars’s moons, to President Obama.
(Illustration Credit 5.13)
CHAPTER SIX
THE MARCH TO MARS
I was an attentive listener when U.S. President Barack Obama declared on April 15, 2010, at the Kennedy Space Center: “By the mid-2030s, I believe we can send humans to orbit Mars and return them safely to Earth.”
To fulfill the President’s promissory note to the future, I believe that the human reach for the red planet involves a stepping-stone approach, first to Phobos, one of two Martian moons. To be sure, our trips with crews to asteroids prepare us for this rung of the ladder to Mars, as Phobos is like a big asteroid.
Phobos is a way station, a perfect perch that becomes the first sustainable habitat on another world. From that mini-world, crews on Phobos can run robotic vehicles on Mars more directly, in a much shorter communication delay time than commands sent from faraway Earth. Robotic stand-ins for astronauts will ready the habitats and other hardware on the Martian surface, in preparation for the first human crew to arrive on Mars. That’s my judgment. My theory right now is that somebody piecing together hardware on Mars through telerobotics on Phobos is the right person to later lead the first landing mission on the red planet.
My approach may well be a contested way to get to Mars, as I’m rubbing up against some unrelenting NASA space planners—but that’s not new for me.
Phobos and Deimos are, in a sense, offshore islands of Mars, discovered in 1877 by Asaph Hall at the U.S. Naval Observatory in Washington, D.C. They were tagged with names from Greek mythology: Phobos means “fear,” Deimos, “terror.” In the future these Martian moons are likely to symbolize just the opposite: courage and security.
Both moons are tidally locked to Mars, as our own moon is relative to Earth: Phobos and Deimos present the same side to Mars all the time.
Phobos is the innermost moon of Mars, only 16.7 miles (26.9 kilometers) in diameter but the larger of the two moons. Diminutive Deimos is a little over 7 miles (11 kilometers) in breadth. Scientifically, both Martian moons are oddballs. There is continual dispute as to where they came from. Just how did they get there? Conjecture about them being captured asteroids or cogenerated with Mars is debatable. These two objects are a cosmic detective story, and we need more clues to sort out their true nature.
Years ago I stirred up a little more than Phobos dust by calling attention to a strange feature spotted on that moon. I termed this oddity a monolith, a very unusual structure. While there are those who view it as a large, rectangular boulder, visiting Phobos can categorize this curious creation, put there by the universe, or God if you prefer.
Phobos and Deimos, two moons, orbit Mars.
(Illustration Credit 6.1)
The good news here is that Phobos orbits Mars at just 5,827 miles (9,377 kilomet
ers) from the planet’s surface. It circles Mars in about eight hours. It is nearer to its parent planet than any other known moon in our solar system. Phobos hurtles around Mars faster than the planet rotates, so future Mars-walkers could see this moon rise and set twice a day. Anyone on Phobos would see how the moon is bathed in reflected light off of the red planet. This “Mars-shine” is akin to earthshine, when sunlight reflects off our planet and illuminates the moon’s night side.
There is, conversely, long-term bad news for Phobos. Due to its short orbital period around Mars, 50 million years hence it will crash into the red planet, or bust into pieces due to gravitational forces.
Phobos is a heavily cratered, irregular body with no atmosphere. The gravity field is very weak—less than one-thousandth the gravity on Earth—making it easier for spacecraft to land and take off. Escape velocity from this moon is just 25 miles an hour. This moon’s most eye-catching feature is Stickney, a six-mile-wide crater. When the object that formed this crater hit Phobos, its impact fashioned streak patterns across the moon’s surface. The day and night sides of the moon have been gauged, showing extreme temperature variations; the sunlit side of Phobos is like a pleasant winter day in Chicago, while only a few miles away, on the dark side of the moon, the temperature is more ruthless than a night in Antarctica.
The PH-D Project
Taking all these factors and others into account, I feel that Phobos may well be the ideal location from which to support a “nonhuman, hands-off Mars” program—at least initially. From Phobos a crew can control rovers and other machines to survey Mars and orchestrate the pre-positioning of habitation modules. A Phobos station can draw upon our accumulated know-how in constructing the modular International Space Station. A laboratory bound for Phobos can be certified for duty at the space station prior to send-off to the Martian moon. The regolith of Phobos can be used to envelop the lab, a way to help protect crews from radiation.
