Asteroid mining is the hypothetical exploitation of materials from asteroids and other minor planets, including near-Earth objects.
Notable asteroid mining challenges include the high cost of spaceflight, unreliable identification of asteroids which are suitable for mining, and the challenges of extracting usable material in a space environment.
Asteroid sample return research missions (see completed missions Hayabusa and Hayabusa2 and in-progress OSIRIS-REx) illustrate the challenges of collecting ore from space using current technology. As of 2021, less than 1 gram of asteroid material has been successfully returned to Earth from space. In progress missions promise to up this amount to approximately 60 grams (two ounces). Asteroid research missions are complex endeavors and return a tiny amount of material (less than 1 milligram Hayabusa, 100 milligrams Hayabusa2, 60 grams planned OSIRIS-REx) relative to the size and expense of these projects ($300 million Hayabusa, $800 million Hayabusa2, $1.16 billion OSIRIS-REx).
After a burst of interest in the 2010s, asteroid mining ambitions have shifted to more distant long-term goals and some 'asteroid mining' companies have pivoted to more general-purpose propulsion technology.
The history of asteroid mining is brief but features a gradual evolution. Ideas of which asteroids to prospect, how to gather resources, and what to do with those resources evolve over the decades.
Before 1970, asteroid mining existed largely within the realm of science fiction. Stories such as Worlds of If, Scavengers in Space, and Miners in the Sky told stories about the conceived dangers, motives, and experiences of mining asteroids. At the same time, many researchers in academia speculated about the profits that could be gained from asteroid mining, but they lacked the technology to seriously pursue the idea.
The 1969 Moon Landing spurred a wave of scientific interest in human space activity far beyond the Earth's orbit. As the decade continued, more and more academic interest surrounded the topic of asteroid mining. A good deal of serious academic consideration was aimed at mining asteroids located closer to Earth than the main asteroid belt. In particular, the asteroid groups Apollo and Amor were considered. These groups were chosen not only because of their proximity to Earth but also because many at the time thought they were rich in raw materials that could be refined.
Despite the wave of interest, many in the space science community were aware of how little was known about asteroids and encouraged a more gradual and systematic approach to asteroid mining.
Academic interest in asteroid mining continued into the 1980s. The idea of targeting the Apollo and Amor asteroid groups still had some popularity. However, by the late 1980s the interest in the Apollo and Amor asteroid groups is being replaced with interest in the moons of Mars, Phobos and Deimos.
Organizations like NASA begin to formulate ideas of how to process materials in space and what to do with the materials that are hypothetically gathered from space.
New reasons emerge for pursuing asteroid mining. These reasons tend to revolve around environmental concerns, such as fears over humans over-consuming the Earth's natural resources and trying to capture energy from the Sun in space.
In the same decade, NASA is trying to establish what materials in asteroids could be valuable for extraction. These materials include free-metals, volatiles, and bulk dirt.
As resource depletion on Earth becomes more real, the idea of extracting valuable elements from asteroids and returning these to Earth for profit, or using space-based resources to build solar-power satellites and space habitats, becomes more attractive. Hypothetically, water processed from ice could refuel orbiting propellant depots.
Although asteroids and Earth accreted from the same starting materials, Earth's relatively stronger gravity pulled all heavy siderophilic (iron-loving) elements into its core during its molten youth more than four billion years ago. This left the crust depleted of such valuable elements until a rain of asteroid impacts re-infused the depleted crust with metals like gold, cobalt, iron, manganese, molybdenum, nickel, osmium, palladium, platinum, rhenium, rhodium, ruthenium and tungsten (some flow from core to surface does occur, e.g. at the Bushveld Igneous Complex, a famously rich source of platinum-group metals). Today, these metals are mined from Earth's crust, and they are essential for economic and technological progress. Hence, the geologic history of Earth may very well set the stage for a future of asteroid mining.
In 2006, the Keck Observatory announced that the binary Jupiter trojan 617 Patroclus, and possibly large numbers of other Jupiter trojans, are likely extinct comets and consist largely of water ice. Similarly, Jupiter-family comets, and possibly near-Earth asteroids that are extinct comets, might also provide water. The process of in-situ resource utilization—using materials native to space for propellant, thermal management, tankage, radiation shielding, and other high-mass components of space infrastructure—could lead to radical reductions in its cost. Although whether these cost reductions could be achieved, and if achieved would offset the enormous infrastructure investment required, is unknown.
From the astrobiological perspective, asteroid prospecting could provide scientific data for the search for extraterrestrial intelligence (SETI). Some astrophysicists have suggested that if advanced extraterrestrial civilizations employed asteroid mining long ago, the hallmarks of these activities might be detectable.
|Earth surface to LEO||8.0 km/s|
|LEO to near-Earth asteroid||5.5 km/s[note 1]|
|LEO to lunar surface||6.3 km/s|
|LEO to moons of Mars||8.0 km/s|
An important factor to consider in target selection is orbital economics, in particular the change in velocity (Δv) and travel time to and from the target. More of the extracted native material must be expended as propellant in higher Δv trajectories, thus less returned as payload. Direct Hohmann trajectories are faster than Hohmann trajectories assisted by planetary and/or lunar flybys, which in turn are faster than those of the Interplanetary Transport Network, but the reduction in transfer time comes at the cost of increased Δv requirements.
The Easily Recoverable Object (ERO) subclass of Near-Earth asteroids are considered likely candidates for early mining activity. Their low Δv makes them suitable for use in extracting construction materials for near-Earth space-based facilities, greatly reducing the economic cost of transporting supplies into Earth orbit.
The table above shows a comparison of Δv requirements for various missions. In terms of propulsion energy requirements, a mission to a near-Earth asteroid compares favorably to alternative mining missions.
An example of a potential target for an early asteroid mining expedition is 4660 Nereus, expected to be mainly enstatite. This body has a very low Δv compared to lifting materials from the surface of the Moon. However, it would require a much longer round-trip to return the material.
Multiple types of asteroids have been identified but the three main types would include the C-type, S-type, and M-type asteroids:
A class of easily retrievable objects (EROs) was identified by a group of researchers in 2013. Twelve asteroids made up the initially identified group, all of which could be potentially mined with present-day rocket technology. Of 9,000 asteroids searched in the NEO database, these twelve could all be brought into an Earth-accessible orbit by changing their velocity by less than 500 meters per second (1,800 km/h; 1,100 mph). The dozen asteroids range in size from 2 to 20 meters (10 to 70 ft).
Main article: B612 Foundation
The B612 Foundation is a private nonprofit foundation with headquarters in the United States, dedicated to protecting Earth from asteroid strikes. As a non-governmental organization it has conducted two lines of related research to help detect asteroids that could one day strike Earth, and find the technological means to divert their path to avoid such collisions.
The foundation's 2013 goal was to design and build a privately financed asteroid-finding space telescope, Sentinel, hoping in 2013 to launch it in 2017–2018. The Sentinel's infrared telescope, once parked in an orbit similar to that of Venus, is designed to help identify threatening asteroids by cataloging 90% of those with diameters larger than 140 metres (460 ft), as well as surveying smaller Solar System objects. After NASA terminated their $30 million funding agreement with the B612 Foundation in October 2015 and the private fundraising did not achieve its goals, the Foundation eventually opted for an alternative approach using a constellation of much smaller spacecraft which is under study as of June 2017[update]. NASA/JPL's NEOCam has been proposed instead.
There are four options for mining:
Processing in situ for the purpose of extracting high-value minerals will reduce the energy requirements for transporting the materials, although the processing facilities must first be transported to the mining site. In situ mining will involve drilling boreholes and injecting hot fluid/gas and allow the useful material to react or melt with the solvent and extract the solute. Due to the weak gravitational fields of asteroids, any activities, like drilling, will cause large disturbances and form dust clouds. These might be confined by some dome or bubble barrier. Or else some means of rapidly dissipating any dust could be provided for.
Mining operations require special equipment to handle the extraction and processing of ore in outer space. The machinery will need to be anchored to the body, but once in place, the ore can be moved about more readily due to the lack of gravity. However, no techniques for refining ore in zero gravity currently exist. Docking with an asteroid might be performed using a harpoon-like process, where a projectile would penetrate the surface to serve as an anchor; then an attached cable would be used to winch the vehicle to the surface, if the asteroid is both penetrable and rigid enough for a harpoon to be effective.
Due to the distance from Earth to an asteroid selected for mining, the round-trip time for communications will be several minutes or more, except during occasional close approaches to Earth by near-Earth asteroids. Thus any mining equipment will either need to be highly automated, or a human presence will be needed nearby. Humans would also be useful for troubleshooting problems and for maintaining the equipment. On the other hand, multi-minute communications delays have not prevented the success of robotic exploration of Mars, and automated systems would be much less expensive to build and deploy.
On April 24, 2012, a plan was announced by billionaire entrepreneurs to mine asteroids for their resources. The company was called Planetary Resources and its founders include aerospace entrepreneurs Eric Anderson and Peter Diamandis. Advisers included film director and explorer James Cameron and investors included Google's chief executive Larry Page. Its executive chairman was Eric Schmidt. They planned to create a fuel depot in space by 2020 by using water from asteroids, splitting it to liquid oxygen and liquid hydrogen for rocket fuel. From there, it could be shipped to Earth orbit for refueling commercial satellites or spacecraft. In 2020, the scheme was wound down and all hardware assets were auctioned off.
Telescope technology was proposed by Planetary Resources to locate and harvest these asteroids has resulted in the plans for three different types of satellites:
In 2018, all plans for The Arkyd space telescope technology were abandoned, and Planetary Resources assets were acquired ConsenSys, a blockchain company with no public space facing goals.
Deep Space Industries, was started in 2013 by David Gump, who had founded other space companies. At the time, the company hoped to begin prospecting for asteroids suitable for mining by 2015 and by 2016 return asteroid samples to Earth. Deep Space Industries planned to begin mining asteroids by 2023. In 2019, Deep Space Industries was acquired by Bradford Space, a company focusing on earth orbit systems and space flight components.
At ISDC-San Diego 2013, Kepler Energy and Space Engineering (KESE, llc) also announced it was going to mine asteroids, using a simpler, more straightforward approach: KESE plans to use almost exclusively existing guidance, navigation and anchoring technologies from mostly successful missions like the Rosetta/Philae, Dawn, and Hayabusa, and current NASA Technology Transfer tooling to build and send a 4-module Automated Mining System (AMS) to a small asteroid with a simple digging tool to collect ≈40 tons of asteroid regolith and bring each of the four return modules back to low Earth orbit (LEO) by the end of the decade. Small asteroids are expected to be loose piles of rubble, therefore providing for easy extraction.
In September 2012, the NASA Institute for Advanced Concepts (NIAC) announced the Robotic Asteroid Prospector project, which will examine and evaluate the feasibility of asteroid mining in terms of means, methods, and systems.
Technology is being developed by TransAstra Corporation to locate and harvest asteroids with the Apis family of spacecraft, which comprises three classes of flight systems:
Currently, the quality of the ore and the consequent cost and mass of equipment required to extract it are unknown and can only be speculated. Some economic analyses indicate that the cost of returning asteroidal materials to Earth far outweighs their market value, and that asteroid mining will not attract private investment at current commodity prices and space transportation costs. Other studies suggest large profit by using solar power. Potential markets for materials can be identified and profit generated if extraction cost is brought down. For example, the delivery of multiple tonnes of water to low Earth orbit for rocket fuel preparation for space tourism could generate a significant profit if space tourism itself proves profitable.
In 1997 it was speculated that a relatively small metallic asteroid with a diameter of 1.6 km (1 mi) contains more than US$20 trillion worth of industrial and precious metals. A comparatively small M-type asteroid with a mean diameter of 1 km (0.62 mi) could contain more than two billion metric tons of iron–nickel ore, or two to three times the world production of 2004. The asteroid 16 Psyche is believed to contain 1.7×1019 kg of nickel–iron, which could supply the world production requirement for several million years. A small portion of the extracted material would also be precious metals.
Not all mined materials from asteroids would be cost-effective, especially for the potential return of economic amounts of material to Earth. For potential return to Earth, platinum is considered very rare in terrestrial geologic formations and therefore is potentially worth bringing some quantity for terrestrial use. Nickel, on the other hand, is quite abundant and being mined in many terrestrial locations, so the high cost of asteroid mining may not make it economically viable.
Although Planetary Resources indicated in 2012 that the platinum from a 30-meter-long (98 ft) asteroid could be worth US$25–50 billion, an economist remarked any outside source of precious metals could lower prices sufficiently to possibly doom the venture by rapidly increasing the available supply of such metals.
Development of an infrastructure for altering asteroid orbits could offer a large return on investment.
Main article: Natural resource § Classification
Scarcity is a fundamental economic problem of humans having seemingly unlimited wants in a world of limited resources. Since Earth's resources are finite, the relative abundance of asteroidal ore gives asteroid mining the potential to provide nearly unlimited resources, which would essentially eliminate scarcity for those materials.
The idea of exhausting resources is not new. In 1798, Thomas Malthus wrote, because resources are ultimately limited, the exponential growth in a population would result in falls in income per capita until poverty and starvation would result as a constricting factor on population. Malthus posited this 224 years ago, and no sign has yet emerged of the Malthus effect regarding raw materials.
Continued development in asteroid mining techniques and technology will help to increase mineral discoveries. As the cost of extracting mineral resources, especially platinum group metals, on Earth rises, the cost of extracting the same resources from celestial bodies declines due to technological innovations around space exploration.
As of September 2016[update], there are 711 known asteroids with a value exceeding US$100 trillion.
Space ventures are high-risk, with long lead times and heavy capital investment, and that is no different for asteroid-mining projects. These types of ventures could be funded through private investment or through government investment. For a commercial venture it can be profitable as long as the revenue earned is greater than total costs (costs for extraction and costs for marketing). The costs involving an asteroid-mining venture have been estimated to be around US$100 billion in 1996.
There are six categories of cost considered for an asteroid mining venture:
Determining financial feasibility is best represented through net present value. One requirement needed for financial feasibility is a high return on investments estimating around 30%. Example calculation assumes for simplicity that the only valuable material on asteroids is platinum. On August 16, 2016, platinum was valued at $1157 per ounce or $37,000 per kilogram. At a price of $1,340, for a 10% return on investment, 173,400 kg (5,575,000 ozt) of platinum would have to be extracted for every 1,155,000 tons of asteroid ore. For a 50% return on investment 1,703,000 kg (54,750,000 ozt) of platinum would have to be extracted for every 11,350,000 tons of asteroid ore. This analysis assumes that doubling the supply of platinum to the market (5.13 million ounces in 2014) would have no effect on the price of platinum. A more realistic assumption is that increasing the supply by this amount would reduce the price 30–50%.
The financial feasibility of asteroid mining with regards to different technical parameters has been presented by Sonter and more recently by Hein et al.
Hein et al. have specifically explored the case where platinum is brought from space to Earth and estimate that economically viable asteroid mining for this specific case would be rather challenging.
Decreases in the price of space access matter. The start of operational use of the low-cost-per-kilogram-in-orbit Falcon Heavy launch vehicle in 2018 is projected by astronomer Martin Elvis to have increased the extent of economically-minable near-Earth asteroids from hundreds to thousands. With the increased availability of several kilometers per second of delta-v that Falcon Heavy provides, it increases the number of NEAs accessible from 3 percent to around 45 percent.
Precedent for joint investment by multiple parties into a long-term venture to mine commodities may be found in the legal concept of a mining partnership, which exists in the state laws of multiple US states including California. In a mining partnership, "[Each] member of a mining partnership shares in the profits and losses thereof in the proportion which the interest or share he or she owns in the mine bears to the whole partnership capital or whole number of shares."
Space law involves a specific set of international treaties, along with national statutory laws. The system and framework for international and domestic laws have emerged in part through the United Nations Office for Outer Space Affairs. The rules, terms and agreements that space law authorities consider to be part of the active body of international space law are the five international space treaties and five UN declarations. Approximately 100 nations and institutions were involved in negotiations. The space treaties cover many major issues such as arms control, non-appropriation of space, freedom of exploration, liability for damages, safety and rescue of astronauts and spacecraft, prevention of harmful interference with space activities and the environment, notification and registration of space activities, and the settlement of disputes. In exchange for assurances from the space power, the nonspacefaring nations acquiesced to U.S. and Soviet proposals to treat outer space as a commons (res communis) territory which belonged to no one state.
Asteroid mining in particular is covered by both international treaties—for example, the Outer Space Treaty—and national statutory laws—for example, specific legislative acts in the United States and Luxembourg.
Varying degrees of criticism exist regarding international space law. Some critics accept the Outer Space Treaty, but reject the Moon Agreement. The Outer Space Treaty allows private property rights for outer space natural resources once removed from the surface, subsurface or subsoil of the Moon and other celestial bodies in outer space. Thus, international space law is capable of managing newly emerging space mining activities, private space transportation, commercial spaceports and commercial space stations/habitats/settlements. Space mining involving the extraction and removal of natural resources from their natural location is allowable under the Outer Space Treaty. Once removed, those natural resources can be reduced to possession, sold, traded and explored or used for scientific purposes. International space law allows space mining, specifically the extraction of natural resources. It is generally understood within the space law authorities that extracting space resources is allowable, even by private companies for profit. However, international space law prohibits property rights over territories and outer space land.
Astrophysicists Carl Sagan and Steven J. Ostro raised the concern altering the trajectories of asteroids near Earth might pose a collision hazard threat. They concluded that orbit engineering has both opportunities and dangers: if controls instituted on orbit-manipulation technology were too tight, future spacefaring could be hampered, but if they were too loose, human civilization would be at risk.
After ten years of negotiations between nearly 100 nations, the Outer Space Treaty opened for signature on January 27, 1966. It entered into force as the constitution for outer space on October 10, 1967. The Outer Space Treaty was well received; it was ratified by ninety-six nations and signed by an additional twenty-seven states. The outcome has been that the basic foundation of international space law consists of five (arguably four) international space treaties, along with various written resolutions and declarations. The main international treaty is the Outer Space Treaty of 1967; it is generally viewed as the "Constitution" for outer space. By ratifying the Outer Space Treaty of 1967, ninety-eight nations agreed that outer space would belong to the "province of mankind", that all nations would have the freedom to "use" and "explore" outer space, and that both these provisions must be done in a way to "benefit all mankind". The province of mankind principle and the other key terms have not yet been specifically defined (Jasentuliyana, 1992). Critics have complained that the Outer Space Treaty is vague. Yet, international space law has worked well and has served space commercial industries and interests for many decades. The taking away and extraction of Moon rocks, for example, has been treated as being legally permissible.
The framers of Outer Space Treaty initially focused on solidifying broad terms first, with the intent to create more specific legal provisions later (Griffin, 1981: 733–734). This is why the members of the COPUOS later expanded the Outer Space Treaty norms by articulating more specific understandings which are found in the "three supplemental agreements" – the Rescue and Return Agreement of 1968, the Liability Convention of 1973, and the Registration Convention of 1976 (734).
Hobe (2007) explains that the Outer Space Treaty "explicitly and implicitly prohibits only the acquisition of territorial property rights" but extracting space resources is allowable. It is generally understood within the space law authorities that extracting space resources is allowable, even by private companies for profit. However, international space law prohibits property rights over territories and outer space land. Hobe further explains that there is no mention of “the question of the extraction of natural resources which means that such use is allowed under the Outer Space Treaty” (2007: 211). He also points out that there is an unsettled question regarding the division of benefits from outer space resources in accordance with Article, paragraph 1 of the Outer Space Treaty.
Main article: Moon Agreement
The Moon Agreement was signed on December 18, 1979, as part of the United Nations Charter and it entered into force in 1984 after a five state ratification consensus procedure, agreed upon by the members of the United Nations Committee on Peaceful Uses of Outer Space (COPUOS). As of September 2019, only 18 nations have signed or ratified the treaty. The other three outer space treaties experienced a high level of international cooperation in terms of signage and ratification, but the Moon Treaty went further than them, by defining the Common Heritage concept in more detail and by imposing specific obligations on the parties engaged in the exploration and/or exploitation of outer space. The Moon Treaty explicitly designates the Moon and its natural resources as part of the Common Heritage of Mankind.
The Article 11 establishes that lunar resources are "not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means." However, exploitation of resources is suggested to be allowed if it is "governed by an international regime" (Article 11.5), but the rules of such regime have not yet been established. S. Neil Hosenball, the NASA General Counsel and chief US negotiator for the Moon Treaty, cautioned in 2018 that negotiation of the rules of the international regime should be delayed until the feasibility of exploitation of lunar resources has been established.
The objection to the treaty by the spacefaring nations is held to be the requirement that extracted resources (and the technology used to that end) must be shared with other nations. The similar regime in the United Nations Convention on the Law of the Sea is believed to impede the development of such industries on the seabed.
The United States, the Russian Federation, and the People's Republic of China (PRC) have neither signed, acceded to, nor ratified the Moon Agreement.
In February 2016, the Government of Luxembourg said that it would attempt to "jump-start an industrial sector to mine asteroid resources in space" by, among other things, creating a "legal framework" and regulatory incentives for companies involved in the industry. By June 2016, it announced that it would "invest more than US$200 million in research, technology demonstration, and in the direct purchase of equity in companies relocating to Luxembourg." In 2017, it became the "first European country to pass a law conferring to companies the ownership of any resources they extract from space", and remained active in advancing space resource public policy in 2018.
In 2017, Japan, Portugal, and the UAE entered into cooperation agreements with Luxembourg for mining operations in celestial bodies.
In 2018, the Luxembourg Space Agency was created. It provides private companies and organizations working on asteroid mining with financial support.
Some nations are beginning to promulgate legal regimes for extraterrestrial resource extraction. For example, the United States "SPACE Act of 2015"—facilitating private development of space resources consistent with US international treaty obligations—passed the US House of Representatives in July 2015. In November 2015 it passed the United States Senate. On 25 November US-President Barack Obama signed the H.R.2262 – U.S. Commercial Space Launch Competitiveness Act into law. The law recognizes the right of U.S. citizens to own space resources they obtain and encourages the commercial exploration and utilization of resources from asteroids. According to the article § 51303 of the law:
A United States citizen engaged in commercial recovery of an asteroid resource or a space resource under this chapter shall be entitled to any asteroid resource or space resource obtained, including to possess, own, transport, use, and sell the asteroid resource or space resource obtained in accordance with applicable law, including the international obligations of the United States
On 6 April 2020 US-President Donald Trump signed the Executive Order on Encouraging International Support for the Recovery and Use of Space Resources. According to the Order:
A positive impact of asteroid mining has been conjectured as being an enabler of transferring industrial activities into space, such as energy generation. A quantitative analysis of the potential environmental benefits of water and platinum mining in space has been developed, where potentially large benefits could materialize, depending on the ratio of material mined in space and mass launched into space.
First successful missions by country:
|USA||ICE (1985)||NEAR (1997)||NEAR (2001)||Stardust (2006)|
|Japan||Suisei (1986)||Hayabusa (2005)||Hayabusa (2005)||Hayabusa (2010)|
|EU||ICE (1985)||Rosetta (2014)||Rosetta (2014)|
|Soviet Union||Vega 1 (1986)|
|China||Chang'e 2 (2012)|
The first mention of asteroid mining in science fiction apparently came in Garrett P. Serviss' story Edison's Conquest of Mars, published in the New York Evening Journal in 1898.
The 1979 film Alien, directed by Ridley Scott, features the crew of the Nostromo, a commercially operated spaceship on a return trip to Earth hauling a refinery and 20 million tons of mineral ore mined from an asteroid.
C. J. Cherryh's 1991 novel, Heavy Time, focuses on the plight of asteroid miners in the Alliance-Union universe, while Moon is a 2009 British science fiction drama film depicting a lunar facility that mines the alternative fuel helium-3 needed to provide energy on Earth. It was notable for its realism and drama, winning several awards internationally.
Several science-fiction video games include asteroid mining. For example, in the space-MMO, EVE Online, asteroid mining is a very popular career, owing to its simplicity.
In The Expanse series of novels, asteroid mining is a driving economic force behind the colonization of the solar system. Since huge energy input is required to escape planets' gravity, the novels imply that once space-based mining platforms are established, it will be more efficient to harvest natural resources (water, oxygen, building materials, etc.) from asteroids rather than lifting them out of Earth's gravity well.
Daniel Suarez's 2019 novel Delta-v describes how asteroid mining could be achieved with today's technology given a bold investment of an enormous amount of capital to construct a sufficiently large spacecraft with today's technology.
The first mining experiments conducted in space could pave the way for new technologies to help humans explore and establish settlements on distant worlds, a study suggests.
We really are trying to demonstrate we can develop the technologies and the techniques to help commercial companies, entrepreneurs and others get to asteroids and mine them.
The Luxembourg government on Feb. 3 announced it would seek to jump-start an industrial sector to mine asteroid resources in space by creating regulatory and financial incentives.
The Government said it planned to create a legal framework for exploiting resources beyond Earth's atmosphere, and said it welcomed private investors and other nations.