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Friday, November 22, 2024

Water on terrestrial planets of the Solar System

The presence of water on the terrestrial planets of the Solar System (Mercury, Venus, Earth, Mars, and the closely related Earth's Moon) varies with each planetary body, with the exact origins remaining unclear. Additionally, the terrestrial dwarf planet Ceres is known to have water ice on its surface.

Water inventories

Mercury

Due to its proximity to the Sun and lack of visible water on its surface, the planet Mercury had been thought of as a non-volatile planet. Data retrieved from the Mariner 10 mission found evidence of hydrogen (H), helium (He), and oxygen (O) in Mercury's exosphere. Volatiles have also been found near the polar regions. MESSENGER, however, sent back data from multiple on-board instruments that led scientists to the conclusion that Mercury was volatile rich. Mercury is rich in potassium (K) which has been suggested as a proxy for volatile depletion on the planetary body. This leads to assumption that Mercury could have accreted water on its surface, relative to that of Earth if its proximity had not been so near that of the Sun.

Venus

The current Venusian atmosphere has only ~200 mg/kg H2O(g) in its atmosphere and the pressure and temperature regime makes water unstable on its surface. Nevertheless, assuming that early Venus's H2O had a ratio between deuterium (heavy hydrogen, 2H) and hydrogen (1H) similar to Earth's Vienna Standard Mean Ocean Water (VSMOW) of 1.6×10−4, the current D/H ratio in the Venusian atmosphere of 1.9×10−2, at nearly ×120 of Earth's, may indicate that Venus had a much larger H2O inventory. While the large disparity between terrestrial and Venusian D/H ratios makes any estimation of Venus's geologically ancient water budget difficult, its mass may have been at least 0.3% of Earth's hydrosphere. Estimates based on Venus's levels of deuterium suggest that the planet has lost anywhere from 4 metres (13 ft) of surface water up to "an Earth's ocean's worth".

Earth

Earth's hydrosphere contains ~1.46×1021 kg (3.22×1021 lb) of H2O and sedimentary rocks contain ~0.21×1021 kg (4.6×1020 lb), for a total crustal inventory of ~1.67×1021 kg (3.68×1021 lb) of H2O. The mantle inventory is poorly constrained in the range of 0.5×1021–4×1021 kg (1.1×1021–8.8×1021 lb). Therefore, the bulk inventory of H2O on Earth can be conservatively estimated as 0.04% of Earth's mass (~2.3×1021 kg (5.1×1021 lb)).

Earth's Moon

Recent observation made by a number of spacecraft confirmed significant amounts of lunar water. The secondary ion mass spectrometer (SIMS) measured H2O as well as other possible volatiles in lunar volcanic glass bubbles. In these volcanic glasses, 4-46 ppm by weight (wt) of H2O was found and then modeled to have been 260-745 ppm wt prior to the lunar volcanic eruptions. SIMS also found lunar water in the rock samples the Apollo astronauts returned to Earth. These rock samples were tested in three different ways and all came to the same conclusion that the Moon contains water.

There are three main data sets for water abundance on the lunar surface: highland samples, KREEP samples, and pyroclastic glass samples. Highlands samples were estimated for the lunar magma ocean at 1320-5000 ppm wt of H2O in the beginning. The urKREEP sample estimates a 130-240 ppm wt of H2O, which is similar to the findings in the current Highland samples (before modeling). Pyroclastic glass sample beads were used to estimate the water content in the mantle source and the bulk silicate Moon. The mantle source was estimated at 110 ppm wt of H2O and the bulk silicate Moon contained 100-300 ppm wt of H2O.

Mars

A significant amount of surface hydrogen has been observed globally by the Mars Odyssey GRS. Stoichiometrically estimated water mass fractions indicate that—when free of carbon dioxide—the near surface at the poles consists almost entirely of water covered by a thin veneer of fine material. This is reinforced by MARSIS observations, with an estimated 1.6×106 km3 (3.8×105 cu mi) of water at the southern polar region with Water Equivalent to a Global layer (WEG) 11 metres (36 ft) deep. Additional observations at both poles suggest the total WEG to be 30 m (98 ft), while the Mars Odyssey NS observations places the lower bound at ~14 cm (5.5 in) depth. Geomorphic evidence favors significantly larger quantities of surface water over geologic history, with WEG as deep as 500 m (1,600 ft). The current atmospheric reservoir of water, though important as a conduit, is insignificant in volume with the WEG no more than 10 μm (0.00039 in). Since the typical surface pressure of the current atmosphere (~6 hPa (0.087 psi)) is less than the triple point of H2O, liquid water is unstable on the surface unless present in sufficiently large volumes. Furthermore, the average global temperature is ~220 K (−53 °C; −64 °F), even below the eutectic freezing point of most brines. For comparison, the highest diurnal surface temperatures at the two MER sites have been ~290 K (17 °C; 62 °F).

Accretion of water by Earth and Mars

The D/H isotopic ratio is a primary constraint on the source of H2O of terrestrial planets. Comparison of the planetary D/H ratios with those of carbonaceous chondrites and comets enables a tentative determination of the source of H2O. The best constraints for accreted H2O are determined from non-atmospheric H2O, as the D/H ratio of the atmospheric component may be subject to rapid alteration by the preferential loss of H  unless it is in isotopic equilibrium with surface H2O. Earth's VSMOW D/H ratio of 1.6×10−4 and modeling of impacts suggest that the cometary contribution to crustal water was less than 10%. However, much of the water could be derived from Mercury-sized planetary embryos that formed in the asteroid belt beyond 2.5 AU. Mars's original D/H ratio as estimated by deconvolving the atmospheric and magmatic D/H components in Martian meteorites (e.g., QUE 94201), is ×(1.9+/-0.25) the VSMOW value. The higher D/H and impact modeling (significantly different from Earth due to Mars's smaller mass) favor a model where Mars accreted a total of 6% to 27% the mass of the current Earth hydrosphere, corresponding respectively to an original D/H between ×1.6 and ×1.2 the SMOW value. The former enhancement is consistent with roughly equal asteroidal and cometary contributions, while the latter would indicate mostly asteroidal contributions. The corresponding WEG would be 0.6–2.7 km (0.37–1.68 mi), consistent with a 50% outgassing efficiency to yield ~500 m (1,600 ft) WEG of surface water. Comparing the current atmospheric D/H ratio of ×5.5 SMOW ratio with the primordial ×1.6 SMOW ratio suggests that ~50 m (160 ft) of has been lost to space via solar wind stripping.

The cometary and asteroidal delivery of water to accreting Earth and Mars has significant caveats, even though it is favored by D/H isotopic ratios. Key issues include:

  1. The higher D/H ratios in Martian meteorites could be a consequence of biased sampling since Mars may have never had an effective crustal recycling process
  2. Earth's Primitive upper mantle estimate of the 187Os/188Os isotopic ratio exceeds 0.129, significantly greater than that of carbonaceous chondrites, but similar to anhydrous ordinary chondrites. This makes it unlikely that planetary embryos compositionally similar to carbonaceous chondrites supplied water to Earth
  3. Earth's atmospheric content of Ne is significantly higher than would be expected had all the rare gases and H2O been accreted from planetary embryos with carbonaceous chondritic compositions.

An alternative to the cometary and asteroidal delivery of H2O would be the accretion via physisorption during the formation of the terrestrial planets in the solar nebula. This would be consistent with the thermodynamic estimate of around two Earth masses of water vapor within 3AU of the solar accretionary disk, which would exceed by a factor of 40 the mass of water needed to accrete the equivalent of 50 Earth hydrospheres (the most extreme estimate of Earth's bulk H2O content) per terrestrial planet. Even though much of the nebular H2O(g) may be lost due to the high temperature environment of the accretionary disk, it is possible for physisorption of H2O on accreting grains to retain nearly three Earth hydrospheres of H2O at 500 K (227 °C; 440 °F) temperatures. This adsorption model would effectively avoid the 187Os/188Os isotopic ratio disparity issue of distally-sourced H2O. However, the current best estimate of the nebular D/H ratio spectroscopically estimated with Jovian and Saturnian atmospheric CH4 is only 2.1×10−5, a factor of 8 lower than Earth's VSMOW ratio. It is unclear how such a difference could exist, if physisorption were indeed the dominant form of H2O accretion for Earth in particular and the terrestrial planets in general.

Asteroid mining

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Asteroid_mining
Overview of the Inner Solar System asteroids up to the Jovian System

Asteroid mining is the hypothetical extraction 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, such as Hayabusa, Hayabusa2, and OSIRIS-REx illustrate the challenges of collecting ore from space using current technology. As of 2024, around 127 grams of asteroid material has been successfully returned to Earth from space. Asteroid research missions are complex endeavors and return a tiny amount of material (less than 100 milligrams Hayabusa, 5.4 grams Hayabusa2, ~121.6 grams OSIRIS-REx) relative to the size and expense of these projects ($300 million Hayabusa, $800 million Hayabusa2, $1.16 billion OSIRIS-REx).

The history of asteroid mining is brief but features a gradual development. Ideas of which asteroids to prospect, how to gather resources, and what to do with those resources have evolved over the decades.

History

Prior to 1970

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 1970s

In 1969, the Apollo 11 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.

The 1980s

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 was 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.

The 1990s

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 was trying to establish what materials in asteroids could be valuable for extraction. These materials included free-metals, volatiles, and bulk dirt.

The 2010s

After a burst of interest in the 2010s, asteroid mining ambitions shifted to more distant long-term goals and some 'asteroid mining' companies have pivoted to more general-purpose propulsion technology.

The 2020s

The 2020s have brought a resurgence of interest, with companies from the United States, Europe, and China renewing their efforts in this ambitious venture. This revival is fueled by a new era of commercial space exploration, significantly driven by SpaceX. Founded by Elon Musk, SpaceX's development of reusable rocket boosters has substantially lowered the cost of space access, reigniting interest and investment in asteroid mining. Even a congressional committee acknowledged this renewed interest by holding a hearing on the topic in December 2023 There are also endeavors to make first-time landings on M-type asteroids to mine metals like Iridium which sells for many thousands per ounce. Private company driven efforts have also given rise to a new culture of secrecy obfuscating which asteroids are identified and targeted for mining missions, whereas previously government-led asteroid research and exploration operated with more transparency.

Minerals in space

As resource depletion on Earth becomes more of a concern, the idea of extracting valuable elements from asteroids and returning them 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.

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.

Mission Δv (km/s)
Earth surface to LEO 8.0
LEO to near-Earth asteroid 5.5
LEO to lunar surface 6.3
LEO to moons of Mars 8.0

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:

  • C-type asteroids have a high abundance of water which is not currently of use for mining but could be used in an exploration effort beyond the asteroid. Mission costs could be reduced by using the available water from the asteroid. C-type asteroids also have high amounts of organic carbon, phosphorus, and other key ingredients for fertilizer which could be used to grow food.
  • S-type asteroids carry little water but are more attractive because they contain numerous metals, including nickel, cobalt, and more valuable metals, such as gold, platinum, and rhodium. A small 10-meter S-type asteroid contains about 650,000 kg (1,433,000 lb) of metal with 50 kg (110 lb) in the form of rare metals like platinum and gold.
  • M-type asteroids are rare but contain up to 10 times more metal than S-types.

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).

Asteroid cataloging

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. NASA/JPL's NEOCam has been proposed instead.

Mining considerations

There are four options for mining:

  1. In-space manufacturing (ISM), which may be enabled by biomining.
  2. Bring raw asteroidal material to Earth for use.
  3. Process asteroidal material on-site to bring back only processed materials, and perhaps produce propellant for the return trip.
  4. Transport the asteroid to a safe orbit around the Moon or Earth or to a space station. This can hypothetically allow for most materials to be used and not wasted.

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.

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.

Mining projects

On April 24, 2012 at the Seattle, Washington Museum of Flight, a plan was announced by billionaire entrepreneurs to mine asteroids for their resources. The company was called Planetary Resources and its founders included aerospace entrepreneurs Eric Anderson and Peter Diamandis. The company announced plans to create a propellant depot in space by 2020; splitting water from asteroids into hydrogen and oxygen to replenish satellites and spacecraft. Advisers included film director and explorer James Cameron; investors included Google's chief executive Larry Page, and its executive chairman was Eric Schmidt. Telescope technology proposed to identify and examine candidate asteroids lead to development of the Arkyd family of spacecraft; two prototypes of which were flown in 2015 and 2018. Shortly after, all plans for the Arkyd space telescope technology were abandoned; the company was wound down, its hardware auctioned off, and remaining assets acquired by ConsenSys, a blockchain company.

A year after the appearance of Planetary Resources, similar asteroid mining plans were announced in 2013 by Deep Space Industries; a company established by David Gump, Rick Tumlinson, and others. The initial goal was to visit asteroids with prospecting and sample return spacecraft in 2015 and 2016; and begin mining within ten years. Deep Space Industries later pivoted to developing & selling the propulsion systems that would enable its envisioned asteroid operations, including a successful line of water-propellant thrusters in 2018; and in 2019 was acquired by Bradford Space, a company with a portfolio of earth orbit systems and space flight components.

Proposed mining projects

At ISDC-San Diego 2013, Kepler Energy and Space Engineering (KESE, llc) announced its intention to send an automated mining system to collect 40 tons of asteroid regolith and return to low Earth orbit by 2020.

In September 2012, the NASA Institute for Advanced Concepts (NIAC) announced the Robotic Asteroid Prospector project, which would examine and evaluate the feasibility of asteroid mining in terms of means, methods, and systems.

The TransAstra Corporation develops technology to locate and harvest asteroids using a family of spacecraft built around a patented approach using concentrated solar energy known as optical mining.

In 2022, a startup called AstroForge announced intentions to develop technologies & spacecraft for prospecting, mining, and refining platinum from near-earth asteroids.

Economics

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 on. 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 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 ironnickel 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 on Earth 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.

Scarcity

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 could 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 226 years ago, and no sign has yet emerged of the Malthus effect regarding raw materials.

  • Proven reserves are deposits of mineral resources that are already discovered and known to be economically extractable under present or similar demand, price and other economic and technological conditions.
  • Conditional reserves are discovered deposits that are not yet economically viable.
  • Indicated reserves are less intensively measured deposits whose data is derived from surveys and geological projections. Hypothetical reserves and speculative resources make up this group of reserves.
  • Inferred reserves are deposits that have been located but not yet exploited.

Continued development in asteroid mining techniques and technology may 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, there are 711 known asteroids with a value exceeding US$100 trillion each.

Financial feasibility

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 were estimated to be around US$100 billion in 1996.

There are six categories of cost considered for an asteroid mining venture:

  1. Research and development costs
  2. Exploration and prospecting costs
  3. Construction and infrastructure development costs
  4. Operational and engineering costs
  5. Environmental costs
  6. Time cost

Determining financial feasibility is best represented through net present value. One requirement needed for financial feasibility is a high return on investment 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 Spacex 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."

Mining the Asteroid Belt from Mars

The asteroids of the inner Solar System and Jupiter: The belt is located between the orbits of Jupiter and Mars.
  Sun
  Jupiter trojans
  Asteroid belt
  Hilda asteroids (Hildas)
  Near-Earth objects (selection)
Main Asteroid Belt 42 largest asteroids

Since Mars is much closer to the asteroid belt than Earth is, it would take less Delta-v to get to the asteroid belt and return minerals to Mars. One hypothesis is that the origin of the Moons of Mars (Phobos and Deimos) are actually asteroid captures from the asteroid belt. 16 Psyche in the main belt could have over $10,000 Quadrillion United States dollar worth of minerals. NASA is planning a mission for October 10, 2023 for the Psyche orbiter to launch and get to the asteroid by August 2029 to study. 511 Davida could have $27 quadrillion worth of minerals and resources. Using the moon Phobos to launch spacecraft is energetically favorable and a useful location from which to dispatch missions to main belt asteroids. Mining the asteroid belt from Mars and its moons could help in the Colonization of Mars.

Phobos as a space elevator for Mars

Space elevator Phobos

Phobos is synchronously orbiting Mars, where the same face stays facing the planet at ~6,028 km above the Martian surface. A space elevator could extend from Phobos to Mars 6,000 km, about 28 kilometers from the surface, and just out of the atmosphere of Mars. A similar space elevator cable could extend out 6,000 km the opposite direction that would counterbalance Phobos. In total the space elevator would extend over 12,000 km which would be below Areostationary orbit of Mars (17,032 km). A rocket launch would be needed to get the rocket and cargo to the beginning of the space elevator 28 km above the surface. The surface of Mars is rotating at 0.25 km/s at the equator and the bottom of the space elevator would be rotating around Mars at 0.77 km/s, so only 0.52 km/s of Delta-v would be needed to get to the space elevator. Phobos orbits at 2.15 km/s and the outer most part of the space elevator would rotate around Mars at 3.52 km/s.

Earth vs Mars vs Moon gravity at elevation

Regulation and safety

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 and 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.

The Outer Space Treaty

Outer Space Treaty:
  Parties
  Signatories
  Non-parties

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.

The Moon Agreement

Participation in the Moon Treaty
  Parties
  Signatories
  Non-parties

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.

Luxembourg

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.

United States

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 U.S. 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 use 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 U.S. President Donald Trump signed the Executive Order on Encouraging International Support for the Recovery and Use of Space Resources. According to the Order:

  • Americans should have the right to engage in commercial exploration, recovery, and use of resources in outer space
  • the US does not view space as a "global commons"
  • the US opposes the Moon Agreement

Environmental impact

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.

Research missions to asteroids and comets

Proposed or cancelled

  • Near Earth Asteroid Prospector – concept for a small commercial spacecraft mission by the private company SpaceDev; the project ran into fundraising difficulties and was subsequently cancelled.
  • VIPER rover – cancelled NASA mission to prospect for lunar resources

Ongoing and planned

  • Hayabusa2 – ongoing JAXA asteroid sample return mission (arrived at the target in 2018, returned sample in 2020)
  • OSIRIS-REx – NASA asteroid sample return mission (launched on September 8, 2016, arrived at target 2020, returned sample on September 24, 2023)
  • Fobos-Grunt 2 – proposed Roskosmos sample return mission to Phobos

Completed

First of successful missions by country:

Nation Flyby Orbit Landing Sample return
 United States ICE (1985) NEAR (1997) NEAR (2001) Stardust (2006), OSIRIS-REx (2023)
 Japan Suisei (1986) Hayabusa (2005) Hayabusa (2005) Hayabusa (2010), Hayabusa2 (2020)
 European Union ICE (1985) Rosetta (2014) Rosetta (2014)
 Soviet Union Vega 1 (1986)


 China Chang'e 2 (2012)


In fiction

An astronaut mining an asteroid using a hand drill in the video game Space Engineers.
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. Several science-fiction video games include asteroid mining.

Religion in space

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Religion_in_space

Astronauts and other spaceflight participants have observed their religions while in space; sometimes publicly, sometimes privately. Religious adherence in outer space poses unique challenges and opportunities for practitioners. Space travelers have reported profound changes in the way they view their faith related to the overview effect, while some secular groups have criticized the use of government spacecraft for religious activities by astronauts.

Christianity

Apollo 8 Genesis Reading

Duration: 1 minute and 56 seconds.
The Apollo 8 Genesis reading.

On Christmas Eve, 1968 astronauts Bill Anders, Jim Lovell, and Frank Borman read from the Book of Genesis as Apollo 8 orbited the Moon. A lawsuit by American Atheists founder Madalyn Murray O'Hair alleged that the observance amounted to a government endorsement of religion in violation of the First Amendment, but the case was dismissed. On August 2, 1971, Apollo 15 Mission Commander David Scott left a Bible on the Lunar rover during extravehicular activity.

ISS crew with festive Christmas hats aboard the Zvezda service module of ISS in 2009.
Christmas morning in Node 3 in 2010.

Protestantism

Apollo 11 astronaut Buzz Aldrin, a Presbyterian, performed a communion service for himself using a kit provided by his church. Aldrin had told flight director Chris Kraft of his plans and intended to broadcast the service back to Earth but opted not to at the request of Deke Slayton, due to the continuing controversy over Apollo 8's reading.

A microfilm Bible that had been to the surface of the Moon was auctioned off in 2011. It was a King James Version created after three astronauts lost their lives in the Apollo 1 fire. Ed White, one of the astronauts who perished, had wanted to take a Bible to the Moon.

On the 2009 STS-128 flight to the International Space Station, astronaut Patrick Forrester brought a fragment of a Missionary Aviation Fellowship aircraft which had been used by the Operation Auca martyrs in Ecuador in 1956.

Several members of the crew of the Space Shuttle Challenger tragedy mission STS-51-L were people of faith. Among them were Commander Dick Scobee and Pilot Michael J. Smith. Scobee was a Baptist who met his wife June at a church social event. After the tragedy, she would go on to write an article in Guidepost Magazine about how their faith helped her through the tragic time. Smith and his family attended a non-denominational Christian church in a community close to their home near Houston's NASA JSC Space Center.

Rick Husband, the Commander of the ill-fated STS-107 Columbia tragedy mission, was also a devout Christian. On the last-request forms that astronauts fill out before every flight, he left his pastor a personal note: "Tell them about Jesus; he's real to me." Later his wife Evelyn wrote a book about their life with him as an astronaut and the importance of their Christian faith entitled High Calling: The Courageous Life and Faith of Space Shuttle Columbia Commander Rick Husband (Audiobook). Likewise, his STS-107 crewmate Michael P. Anderson was also a devout Christian and when not on a mission for NASA, was an active member of the Grace Community Church choir.

Catholicism

A signed message from Pope Paul VI was included among statements from dozens of other world leaders left on the Moon on a silicon disk during the Apollo 11 mission. Following the mission, William Donald Borders, Bishop of the Roman Catholic Diocese of Orlando, told the Pope that the 1917 Code of Canon Law placed the Moon within his diocese, as the first explorers had departed from Cape Kennedy which was under his jurisdiction. The claim was neither confirmed nor denied by the Pope, and the Moon is not recognized as part of the diocese in any official capacity.

The Blessed Sacrament (the body and blood of Christ in the form of consecrated sacramental bread and wine) has been carried into space at least twice. Three Catholic astronauts on Space Shuttle mission STS-59 received Holy Communion on 17 April 1994. NASA astronaut Michael S. Hopkins took a supply of six consecrated hosts to the International Space Station in September 2013, allowing him to receive the Eucharist weekly during his 24-week mission.

In May 2011, Pope Benedict XVI of the Catholic Church talked to the crew of the Space Shuttle Endeavour while it was in Earth orbit.

Russian Orthodox

A Russian Orthodox priest blesses the Soyuz rocket for ISS Expedition 31

Russian Orthodox Christmas was celebrated on the International Space Station, on January 7, 2011. Cosmonauts had the day off, but one of the other crew posted on Twitter, "Merry Christmas to all Russia." The whole crew also celebrated on December 25, two weeks prior.

Cosmonauts sometimes at the request of Russian Orthodox church carry religious icons to space, which upon return to Earth are distributed to churches.

Islam

Muslims in space struggle with fulfilling their religious obligations including kneeling and facing Mecca to pray in microgravity traveling at several kilometres per second. The issue first came up when Sultan bin Salman bin Abdulaziz Al Saud, a Saudi prince, flew aboard STS-51-G and again when Anousheh Ansari flew as a tourist to the International Space Station. In preparation for Malaysian Sheikh Muszaphar Shukor's trip to the ISS in 2007, the National Fatwa Council created "Muslim Obligations in the International Space Station" outlining permissible modifications to rituals such as kneeling when praying (not required in space), facing Mecca (or just Earth) when praying (left to the astronaut's best abilities at the start of prayer), and washing (a wet towel will suffice).

In February 2014, the General Authority of Islamic Affairs and Endowment (GAIAE) from Saudi Arabia issued a fatwa forbidding devout Muslims from participating as crew members in Mars One's proposed one-way mission to Mars. Speaking for the clerical group, Farooq Hamada explained that, "Protecting life against all possible dangers and keeping it safe is an issue agreed upon by all religions and is clearly stipulated in verse 4/29 of the Holy Quran: Do not kill yourselves or one another. Indeed, Allah is to you ever Merciful."

Judaism

Time and date-related observances are important in Judaism, and there have been considerations on the observance of time by Jewish astronauts.

American astronaut Jeffrey Hoffman took multiple Jewish objects to space on his space flights from 1985 to 1996: a miniature Torah scroll, a yad, a Torah breastplate, mezuzot, menorahs, a dreidel, hand-woven tallit, and kiddush cups.

In January 2003, a microfilm Torah, a handwritten copy of the Shabbat kiddush, and a miniature Torah scroll rescued from the Bergen-Belsen concentration camp were taken to space by Israeli astronaut Ilan Ramon aboard the Space Shuttle Columbia. Ramon and the rest of the crew died when the shuttle disintegrated during reentry. In September 2006, Canadian astronaut Steve MacLean took another Torah from Bergen-Belsen aboard the Space Shuttle Atlantis to the International Space Station as a tribute to Ramon.

Hinduism

In December 2006, American astronaut Sunita Williams took a copy of the Bhagavad Gita to the International Space Station. In July 2012, she took there an Om symbol and a copy of the Upanishads.

On 27 February 2021, SDSAT a 3U cubesat launched aboard PSLV-C51 carried a digital copy of Bhagavad Gita into space in an SD card.

Streaming algorithm

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Streaming_algorithm ...