Saving the Planet

How the space industry can contribute.

Introduction

In recent years it has become known worldwide that the Earth is becoming inhospitable, and that now more than ever, society needs to change before the damage becomes irreparable. The chosen theme on the matter is the world’s energy crisis. That is, how the world’s demand for natural resources, used in powering an industrial civilization is largely exceeding the supply of those very resources. Whether these resources be renewable or not, we are simply running out. Renewable energy sources take the course of hundreds of thousands of years to replenish themselves and the most widely used fuel source, fossil fuels release harmful greenhouse gasses further adding to global warming effects. Thus, the need for alternatives is high, the following will take an in-depth look at potential ideas stemming from various aspects within the space industry to aid in finding a solution to save the planet, whilst considering benefits, the implications and feasibility whilst accounting for timescale, laws and policies to abide by.

The Wider Issues

Alongside the main issue covered in this report, there is also a multitude of other issues that the space industry has or could help in solving. The issues can range from monitoring the Earth’s temperatures and gas levels to the huge amount of space debris and how reducing that could be done and why it would be beneficial.

Earth Monitoring

Monitoring the earth comes in many forms and some can make a huge difference in the way we live our lives, some of the more important measures we take from the earth are the weather patterns, gas build-ups (especially of sulphur and carbon dioxide) It can even be used to measure and track tectonic movements. All of these abilities are vital in not only understanding our planet better but also ensuring that we can track global events and plan before they become a crisis. The currently most common use of this technology would be in predicting the weather this is done via satellites such as the Meteosat satellites these are mostly used to provide your weather reports however have a big role to play in predicting natural disasters and their paths. For example, a system of satellites which were part of the Copernicus programme was used to predict and warn local authorities of the destructive path of storm Desmond in 2015 [1], and therefore saved thousands of lives in the process.

Earth monitoring is also incredibly useful when it comes to another natural event that can cause serious damage to surrounding areas and that is a volcanic activity as through Earth monitoring they can measure and assess the likelihood of an eruption due to the increase in gas levels produced by volcanoes, this can often signify an eruption is imminent and it means that authorities can plan ahead and local and international help can be placed on standby resulting in a faster response to the eruption if it occurs.

It can also assist in humanitarian crises such as world hunger as satellite imagery can be used to identify crop yield through a magnified view of each pixel which then allows farmers to have a better knowledge of when to water, fertilize and harvest their crops. We can also create a Vegetation index using specific spectral bands, this is useful in showing crop yield productivity given that 37% of the earth’s landmass is agricultural areas [2].

In the future satellite, mega-constellations are likely to take over from the current satellites in a vast amount of aspects mainly focused around data transfer, these will also increase throughput and global coverage for services such as the internet that will benefit billions of people especially those in harder to reach areas of the Earth.

Space Travel

One of the more widely publicized topics that the space industry is a part of is commercial space travel and then long term space travel in the future, these are important not just due to the factor of taking a trip into space for a short period becoming more accessible, but it will also most likely be the future of the human race. With the efforts about getting to Mars and further, these would all require space travel in a more commercial sense and not just astronauts.

This has been fueled by the recent “race” of several companies to be the first to make commercial space flights for the populous, companies such as SpaceX, Blue Origin and Virgin Galactic have all been looking into more commercial uses for space flight. Blue Origin and Virgin Galactic who have specialized in suborbital space tourism, this is so that you can enjoy the views of space for a short period and even experience “weightlessness”, However, due to the current cost of these flights the tickets are not widely available. On the other hand, SpaceX has been focused on developing reusable rockets and has been running supply missions to the International Space Station since 2012, but as of May 2020, they were able to take NASA astronauts Doug Hurley and Bob Behnken to the ISS using the company’s Crew Dragon spacecraft. [3] Companies such as Boeing are also in the process of 4 developing spacecraft and the Starliner spacecraft is planned to be used in 2021 to carry astronauts to the ISS. The benefits of NASA using private companies that are also able to use multiuse rockets should result in a dramatic reduction in the cost of spaceflights and this would lead to greater opportunities. This would be essential if we wanted to make space travel more commercially viable and allow some citizens to even visit space as if you were simply going abroad. This is not only a great new market but it would be essential in future endeavors into space and in settling planets in the future such as Mars as the technology and research would have already been done and the concern that something may not work correctly would have already been tested and shown.

Another vital part of space travel and especially long term staying on moons and planets are habitable areas, as building from scratch won’t be easily available or even easy to do it is essential that we have alternatives to the conventional structures and this is where companies such as Bigelow Aerospace are focused in designing and testing future living spaces. They currently are testing out their Expandable Activity Module (BEAM) by having it attached to the International Space Station. They also are developing the B330 which is a fully autonomous standalone space station, again designed to make living in space easier. Both of these designs are effective because of the ability to transport them without needing any special rockets and can be transported via the SpaceX Dragon in the case of the BEAM and then expanding upon arrival to create a large amount of space quickly and easily.

Orbital Clean

Up Another major hurdle in space is the disposal of satellites, as currently there are around 2000 live satellites and more than 3000 failed ones [4] and as already mentioned in the report this is only going to increase as technology improves, with mega-constellations each containing hundreds of satellites there is a huge demand to be able to remove unwanted or unused satellites to free up space in the orbit. The amount of debris is also ever-increasing even if space launches were halted as collisions between items generate more debris [4].

This is why missions such as Clearspace-1 are vital in our future of space exploration and usage. This mission currently planned for 2025 will be specifically targeting the Vespa (Vega Secondary Payload Adapter) upper stage which was left in an orbit of around 800km by 660 km altitude orbit after the second launch flight of the Vega launcher, The Vespa is similar to a small satellite and weighs 100kg [4], it has a relatively simple shape and is sturdier than other objects meaning it’s a better target for a first goal as a failure may not result in a large amount of debris being added to the area.

The current idea is to focus on this size of object eventually getting large and then progressing onto multi-object capture, this will not only be essential in the future but is also essential for any space travel as all the debris is currently having to be accounted for on flight paths if going through the specific altitudes.

Discussion: Solving the Energy Problem

The Space industry involves economic activities like manufacturing of components to be taken to space and all the services related to its journey in space. Energy plays a vital role in supporting these operations. The type of energies that currently in use to support these activities are Chemical and Solar Energy.

• Chemical Energy: The spacecraft is powered by the chemical energy generated from the stored fuels. The fuels are used in Liquid (liquid fuels and oxidizer for combustion), Solid (fuel and oxidizer which are premixed in a solid form) and Hybrid (fuel is in the solid form and the oxidizer is in liquid form) forms.
• Solar Energy: The solar rays which are trapped on-board are converted into electric power to power the spacecraft. These Electrically powered spacecraft system uses very less propellant compared to the chemical rockets as they have higher exhaust speed compared to the chemical rockets. Also, the electric propulsions provide small thrust for the long-duration time which makes it easier to achieve high speeds over long periods to work better in deep space missions.
• Energy storage: There is a lot of energy required to support the space sector, hence energy storage is very much important to keep the industries working at times of crises. Currently, the electric power was largely generated by burning the fossil fuels, more the fuel was burned the energy was generated. But due to the concerns with air pollutions and global warming, it has led to the growth of renewable energy such as wind power, and solar power which is cost-efficient and long-lasting. Storage of these energies are done using multiple ways as follows: Figure 3: The conical upper part of the payload that delivered Proba-V into Orbit 6 Batteries: Batteries are the most widely used systems on the earth to store energy. Most used batteries are the lithium-ion batteries, as they can attain very high energy storage over mass ratio compared to others. Even in the space as mass if the critical factor for batteries, the LI-ion cells were widely used in space applications. Hydrogen cells/Fuel cells: These are the cells which convert the chemical energy of a fuel and an oxidizer into electrical energy. These cells can only be powered if there is a continuous source of fuel and oxygen to sustain the chemical reaction compared to other batteries where the chemical energy is usually derived from the metals and its ions.
• Thermal storage: It is the technology which stocks thermal energy by either heating or cooling storage so that the stored energy can later be used for power generation. Apart from this, the most practical solar heating panels provide high storage of energy from a few hours to a day’s worth of energy collected.
• Mechanical storage: These are one of the innovative technologies which trap the gravitational and kinetic energy to store electricity.

The Future

• Energy Consumption

The society is still struggling to implement solar energy methods on the surface of the earth and also, due to high consumption of energy which is extracted, the resources may run out, which will not be able to support the global population that is expected to reach 9 billion by 2050. Hence methods of generating large quantities of energy must be figured out.

Scientists believe that trapping energy from outer space and transferring it to earth may be the future of having an economical and inexhaustible source of clean energy. On earth even though the solar power is moderately used during day times, it is significantly reduced by nights, cloud cover, atmosphere and seasonality. But in the space sun is always shining and there are no obstacles to reduce the intensity of sun rays. This concept of observing solar power and wirelessly transmitting was first described by Isaac Asimov in 1941. Even though the idea seemed technically feasible, it was considered economically unrealistic at the time of research. Over a few decades, the technologies have been evolving to make it happen.

Idea: The idea is to place and position the solar power station or panels in the otter space, where the intensity of sunlight is more reliable and cleaner. 7 Also, it can remain an inexhaustible source of energy.

Working: It can be achieved by using the concept of NASA’s Dragonfly project, which is designed to enable the satellite to self-assemble robotically in earth’s orbit. The satellites are launched to the space attached with reflectors and a microwave or a laser power transmitter, which will convert solar power either into a microwave or a laser beam that is directed down to earth. Once this beam reaches the earth’s surface, the power receiver stations will help convert it into electrical grids. To make this idea cost-efficient companies like SpaceX and Blue origin are decreasing the cost of orbital delivery by making use of reusable rockets. Also, as mentioned earlier the proposed concept of space elevators will be in use to transport any kind of cargo or satellite equipment’s up or down the cord making the deliveries much more efficient rather than using large rockets. This completed solar panels could generate a constant flow of 1500–2000 gigawatts of power which is more, compared to the existing solar farms which generate a maximum of 1.8 gigawatts.

• Asteroid mining:

The world’s energy crisis is posing an ever-growing threat to society as we know it. As the demand for the planet’s natural resources rises and the supply dwindles, we are left with an unavoidable issue which left to its own devices will lead to catastrophic consequences on a global scale. To put into perspective how real of an issue this crisis is, let us look at how if global usage rates either plateau or further increase still, how many years of supply we have remaining on the Earth. According to an article [5] from ‘DORECYCLING’ Oil usage as of 2016 is almost 200 million tonnes per year globally, this correlates to approximately 40 years of oil supplies left at our disposal. Even a resource such as coal which has the largest reserves remaining will run out after 40 years if predicted upward trends come to fruition and 120 years if rates stay as they are albeit highly unlikely. Freshwater makes up 2% of all water on Earth and in the form of water we all drink, the article states “It is predicted that after about 10 years 2/5 of the world population will live in water deficit.” If aluminium demands continue rising, then it will last for around 70 years. These resources will barely look to even last for the next 100 years, in a few generations time, what will remain? Alternative renewable energy sources are needed, however current methods in this field are not able to take the place of the widely used fossil fuels for the time being. Until then it may be useful to acquire natural resources directly from the source that is the very asteroids themselves which brought these materials to the Earth’s crust. I will discuss asteroid mining as a possible means for procuring natural resources that civilization so readily needs to the power industry.

The core idea of my proposal is to mine the materials of interest from asteroids rather than mining them from the Earth. There are different classifications of asteroids dependent on the minerals and ores they possess. C-type asteroids are the most common and consist of clay and silicate rocks, Stypes are made up of silicate materials, nickel-iron and magnesium, M-types are metallic containing nickel-iron. Spectroscopic analyses [6] show other materials such as platinum group metals and volatiles such as water to be present amongst asteroids. When locating a suitable target, one must consider the velocity of the target, as especially in the early phases of the mining industry they will be the most Easily Recoverable Objects (ERO), a subcategory of Near Earth Asteroids (NEO’s). The location of asteroids ranges anywhere between, Earth’s surface and Low Earth Orbit (LEO) and NEO, anything greater will require much more advanced space travel technology which current society has not yet affordably or reliably have.

Mining and processing an asteroid in some respects is simpler to mining on Earth, there is no need for complex chemical processing or waste disposal management. However, mining on a near zerogravity environment poses other challenges that Earth does not. Your standard type-c asteroid is likely to be crumbly but can also vary and be from pure metal to a powder consistency. To dig away at the asteroid this would require the cutting edge to be held against the surface, without gravity to assist with this, cables, harpoons or even nets would need to be embedded into the asteroid. There are many different techniques one could adopt; these include strip mining (scraping the asteroid’s surface) or tunnelling (digging down into veins of ore and tapping into the supply) to name a few. Strip mining would lead to lots of dirt and loose rocks flying up as the gravity is so low on the asteroid, however, to make use of this situation having a large canopy over the mining site will allow for this debris to be collected up and stored. Once collected the material can be put through magnetic fields to separate the nickel-iron granules from the silicate. When mining on a NEO the use of a canopy will be a necessity so that loose rocks do not end up on collision courses with other asteroids or large rocks which could knock them into a different orbit heading straight into the Earth. The benefits of the canopy method are that it is simple, highly reliable and with minimal risk of a machinery breakdown, therefore making this a very feasible option. However, the cost of such an operation could be around $100 Billion which is such a large amount when the possible yield of valuable ore can be meagre. With that in mind, the potential earnings are leaps and bounds more than the costs although it will take some time before the process becomes efficient enough where costs are reduced. Depending on the materials extracted i.e., water, nickel-iron, silicate rocks and hydrocarbons a value of $500,000 per ton can be expected. Whereas a material such as platinum has a value of approximately $30 per gram which translates to $30,000,000 per ton. The possible returns of mining the right asteroids can be anywhere between $4–83 Billion, particular asteroids to target would be Ryugu, Didymos and Psyche as these pose greater yields of resources. Therefore, mining asteroids is quite the gamble but one that can pay off, and when it does it will only make this promising field even more prospective as more efficiently and cheaper can asteroids be mined for their precious resources thus allowing the Earth more time to replenish its supplies as well as providing scientists with the opportunity to develop renewable energy sources.

Important factors to take into consideration are the laws and regulations in place governing asteroid mining. The Outer Space Treaty of 1967 states that it 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” [7]. Moreover, no nation can own an asteroid however anyone can mine them and then the resources taken from the asteroid is their property. This is also backed by the Commercial Space Launch Competitiveness Act which says “A US citizen… shall be entitled to any asteroid resource or space resource obtained, including to possess, own, transport, use, and sell the asteroid resource…” [8].

In conclusion, the effects of asteroid mining on the energy crisis will have a positive impact on society. By undertaking industrial activities in space on asteroids as opposed to the Earth itself the environmental benefits will be high. However, production and carrying out the operation has a large cost meaning if it were to fail or go wrong the consequences on life on Earth could be devastating. If it is a success, then the rewards are untold. Completing this operation will open up a whole new industry which will inject so much finance into the space sector further allowing more ambitious missions to be carried out. This idea is feasible and should be attempted with appropriate caution.

Gravitational energy

usage 9 Three main concepts are potentially viable that utilize gravitational potential energy to aid space exploration, being space elevators, skyhooks and planetary gravity assists. Space elevator consisting of a tether that links the surface of the earth to a satellite in geo-stationery orbit. This would allow cargo to traverse up or down the cord making delivery of payloads into space far more efficient and opening the possibility of construction in space whether this is as a staging point for spacecraft or a research facility. A space elevator would largely supersede the need for land-based rocket launch platforms, which would be beneficial due to the current low payload to launch platform weight ratio and the reduced environmental impact. The issue is that no material known currently has the correct properties to support its weight at the lengths necessary to reach geostationary orbit as well as the engineering feat it would take to produce a strand of material that long. So far only carbon nanotubes have shown the potential of meeting the design envelope to achieve this demonstrated in ‘Table 1’. Alternatively, a skyhook may be a realist means to support exploration it could utilize real technology available currently. A skyhook is a device in low earth orbit that has two tethers spread out radially. As this spins pro grad in its orbit anything attached to the higher tether is accelerated due to angular velocity and the end lower in the orbit is slower relative to the ground which reduces and atmospheric drag which may occur as well as allowing easier attachment of spacecraft. Disadvantages to this are that atmospheric drag still occurs meaning energy is still needed to keep this stable this can be with onboard engines or capturing of incoming higher velocity craft can be synchronized with outgoing vehicles to ensure the conservation of momentum. However, this would rely on sufficient traffic between incoming/ outgoing craft which is a possibility with mars colonization. Gravitational assists have been used in space travel to provide additional momentum to spacecraft since the start of the space industry ‘Figure 4’ shows voyager 2 and how it passed 4 planets collecting data as it went as well as converted potential gravitational energy to kinetic as it passed each body. Unfortunately, this normally involves multiyear activity, making them infeasible for manned space missions.

Planets exploration for finding new energy resource:

There is abundant energy in space and it’s constantly flooded by electromagnetic energy. All-stars in this vast universe produce energy and transmit that energy into space. Planets, asteroids reflect that energy. We are largely dependent on the energy that is generated from fossil fuels. Fossil fuels come from living entities that are dead decomposed and become a part of earth geology. These are extracted from the ground and utilized for several uses of mankind.

Sooner in the near future, the world needs to find new sources of clean energy. Space is our new energy source frontier, and it is flooded with a vast number of planets, stars, etc. so people are looking for new possible ways to find different ways of extracting energy from other exoplanets. As for most of the exoplanets discovered so far are in the small region of our Milky Way galaxy and there are more planets than the stars in the galaxy. By measuring and finding the sizes and weights of these planets we can be able to know the compositions ranging from very rocky (like Venus and earth) to very gas-rich (like Saturn and Jupiter). Exoplanets are made of elements that are similar to the composition that is available on the earth but with different composition mixtures like some planets are dominated by ice or water, and others are dominated by carbon, iron, and some are covered in molten sea lava worlds. [9]

In recent years, a series of missions are successfully launched and provide us with a greater scope into the future with numerous numbers of possible energy sources from different planets in the galaxy. The cutting-edge technology in the space industry that has been developing for years will help to bring energy sources to mankind in the future. From the recent finding on Mars planet, it had an abundance of chemical building blocks, liquid water and energy sources (volcanic activity) to power the chemical reactions that make life possible. So, it is possible to transport the energy wirelessly back to earth with the help of renewable power farms and applicable transportation systems. In the future developing the new hardware needed to capture and transmit solar power and also developing a space power transportation system and launching the system into space, will be a challenging task. [10]

The energy sources in planetary bodies are the combination of heat reservoirs and heat engines. The heat reservoirs store internal energy, and the heat engines convert thermal energy into various types of energies such as mechanical, electrical, and chemical energies. This is true for all active planetary bodies regardless of their composition (ice, gases, or rocks) or size and it varies throughout the solar system. [11]

Near future space propulsion:

In the future, we want a power source that can handle extreme environments and one that may become a permanent fixture source for deep space missions in the coming decades. Recently to address energy-specific challenges NASA and ARPA-e believe and have the potential to improve future space power systems.

• Innovative power management and distribution that includes wireless power transfer and smart grids
• High-energy density batteries and supercapacitors
• Small fission-power systems 
• Hydrogen fuel cells and regenerative fuel cells [12]

With the present technology radioisotope power systems are used for variable space missions. Radioisotopes power systems (RPSs) convert heat from the decay of the radioactive isotope plutonium-238 into electricity and these are capable of producing heat and electricity under harsh conditions. It works even when there is no source of solar or light energy. They have proven safe, reliable and maintenance-free. In the future, we can expect this technology with further improvements, and this becomes an alternate fuel source for space missions to save energy [13]

Far future

Developments in quantum drive technology:

The space agencies are working hard in developing new technology to reduce the fuel requirements in space transportation. According to the study conducted last year by NASA scientists has become the first highest-profile piece of evidence in favor of an impossible space thruster design that has been evoking worldwide skepticism.

It is called by many different names like EmDrive, Q-drive. It works on the principal by converting electricity into microwaves and channeling this electromagnetic radiation through a conical chamber. In theory, the microwaves can exert a force against the wall of the chamber to produce enough thrust to propel a spacecraft in space and make it more reliable and energy-efficient and helps to transport energy resources back to earth. At this point, it is still in laboratory testing prototype and results are unpredictable to tell the working probability in real-time scenarios. If this technology works in a few years this could be the biggest breakthrough in the history of the space industry.

These are the possible technologies we can expect from the space industry to contribute towards saving planet earth with energy crises. [14]

Terraforming

It is important to define terraforming as there is a common misconception that is a far-future technology to inhabit inhospitable planets. This is technically true however it also encompasses any control humans have over an environment to make it more hospitable for example a company called Giaura [15] aims to capture carbon from the air and store it in a solid form. This is a form of 12 terraforming. Commonly referred to as direct air capture many companies notably bill gate’s Carbon Engineering aim to develop a cost-effective way to turn carbon from the air into usable fuel. This would be extremely beneficial as it gives an extra supply of renewable energy that can be utilized to make the world more sustainable. However chemical by-products have to be carefully managed as they can be harmful and may negate any environmental benefit this system may have. Additionally, the process is still very costly making it less cost-effective compared to other environmental methods like planting trees. In conclusion, this method isn’t viable yet however with substantial investment over the next 20 year it could become a top contender for a viable eco-friendly fuel source.

Dyson sphere

The Dyson sphere is a concept first thought of in 1959 [15] where a sphere around a star at the distance that would sustain life. The inside of the sphere could be inhabited and the energy of the star collected through solar energy farm. This would class the civilization type 2 on the Kardashev scale. This concept demonstrates perfect energy usage optimization for an advanced civilization, a goal that would solve the problem in its entirety.

Conclusion

In conclusion, many possible solutions have been highlighted that potentiality may solve the energy crisis in space. However, no one solution can solely be used to completely eradicate the issue. Many solutions have problems of their own or side effects that mean they can’t address the solution as a whole such as the skyhook having atmospheric drag and problems with mining in zero gravity environments in regards to asteroid mining. In time these problems can be overcome but will it be in time to save the planet? That is why it is important now to consider where we should focus our resources to correctly optimize the future benefits there. For example, the would-be no point in developing radioactive isotope engines if a cheaper more efficient electric style engine has been developed. No guarantee can be drawn from this paper as the future is unpredictable meaning none of these solutions is going to work. However, stating this with an educated base roughly it can be predicted the landscape of future technologies for solving energy problems.

Asteroid mining is possible within 20 years and would be an effective solution. However, travel time and risk may mean investment in spacecraft sent to asteroids may be delayed due to the economic recovery of coronavirus and generally due to a long time before returns will be seen.

Elon musk has made huge strides towards beginning to head towards mars and it could be that in the next 20 years we see the first men on Mars.

The background research on related topics can give us an understanding of trends that develop from tech research in the field. Additionally, it gives the impression of what goals that currently exist within the agendas of space companies and agencies.

References

[1] S. Shingles, “Monitoring the Earth from Space,” National Space Centre, 13 November 2019. [Online]. Available: https://spacecentre.co.uk/blog-post/monitoring-the-earth-from-space/. [Accessed 5 December 2020].

[2] D. Taylor, “Space technologies can help solve Earth’s challenges,” Space, 11 May 2020. [Online]. Available: https://www.space.com/space-technologies-help-solve-earthchallenges.html. [Accessed 5 December 2020].

[3] N. Drake, “The future of spaceflight — from orbital vacations to humans on Mars,” National Geographic, 2020. [Online]. Available: https://www.nationalgeographic.com/science/space/space-exploration/future-spaceflight/. [Accessed 5 December 2020].

[4] European Space Agency, “ESA commissions world’s first space debris removal,” 9 December 2019. [Online]. Available: https://www.esa.int/Safety_Security/Clean_Space/ESA_commissions_world_s_first_space_de bris_removal. [Accessed 7 December 2020].

[5] Jeremy, “How much natural resources we have left?,” 29 January 2016. [Online]. Available: https://dorecycling.com/blog/2016/01/29/how-much-natural-resources-we-have-left/. [Accessed 8 December 2020].

[6] M. Sonter, “Asteroid Mining: Key to the Space Economy,” 9 February 2006. [Online]. Available: https://www.space.com/2032-asteroid-mining-key-space-economy.html. [Accessed 8 December 2020].

[7] Wikipedia, “Asteroid mining,” 2020. [Online]. Available: https://en.wikipedia.org/wiki/Asteroid_mining#The_Outer_Space_Treaty. [Accessed 8 December 2020].

[8] The Reeves Law Group, “IS ASTEROID MINING LEGAL YET?,” 2017. [Online]. Available: https://www.robertreeveslaw.com/blog/asteroid-mining/. [Accessed 8 December 2020].

[9] NASA, “NASA exoplanet exploration,” [Online]. Available: https://exoplanets.nasa.gov/whatis-an-exoplanet/overview/. [Accessed 06 12 2020].

[10] N. NOTMAN, “Life — but not as we know it,” 19–01–2018. [Online]. Available: https://www.chemistryworld.com/features/life-on-other-planets/3008503.article. [Accessed 06 12 2020].

[11] A. P. Douce, “ Energy sources in planetary bodies,” 2011. [Online]. Available: https://www.cambridge.org/core/books/thermodynamics-of-the-earth-and-planets/energysources-in-planetary-bodies/56453BCD37EDE66C6756CFEA032EDB11. [Accessed 07 12 2020].

[12] S. Davis, “What are Your Energy Ideas to Enhance Space Exploration and Life on Earth?,” 05- 04–2018. [Online]. Available: https://www.powerelectronics.com/technologies/alternativeenergy/article/21864135/what-are-your-energy-ideas-to-enhance-space-exploration-and-lifeon-earth. [Accessed 06 12 2020].

[13] O. O. N. ENERGY, “Space and Defense Power Systems,” [Online]. Available: https://www.energy.gov/ne/nuclear-reactor-technologies/space-power-systems. [Accessed 06 12 2020].

[14] D. OBERHAUS, “A Mythical Form of Space Propulsion Finally Gets a Real Test,” 06.05.2019. [Online]. Available: https://www.wired.com/story/a-mythical-form-of-space-propulsionfinally-gets-a-real-test/. [Accessed 06 12 2020].

[15] National Aeronautics and Space Administartion, “NASA,” 2020. [Online]. Available: https://www.nasa.gov/. [Accessed 8 December 2020].

[16] Bigelow Aerospace, “BEAM,” Bigelow Aerospace, 2018. [Online]. Available: https://www.bigelowaerospace.com/pages/beam/. [Accessed 7th December 2020].

[17] NASA, “60 Years and Counting,” [Online]. Available: https://www.nasa.gov/specials/60counting/future.html. [Accessed 7 December 2020].

[18] S. Snowden, “Solar Power Stations In Space Could Supply The World With Limitless Energy,” Forbes, 12 March 2019. [Online]. Available: https://www.forbes.com/sites/scottsnowden/2019/03/12/solar-power-stations-in-spacecould-supply-the-world-with-limitless-energy/?sh=6316c6a64386. [Accessed 4 December 2020].

[19] Energy Storage Association, “Why Energy storage Technologies of energy storage,” ESA, 2020. [Online]. Available: https://energystorage.org/why-energy-storage/technologies/. [Accessed 5 December 2020].

[20] D. Wood, “Space-Based Solar Power,” US Department of Energy, 6 March 2014. [Online]. Available: https://www.energy.gov/articles/space-based-solar-power. [Accessed 5 December 2020].

[21] H. Ritchie and M. Roser, “Energy,” Our World in Data, 2014. [Online]. Available: https://ourworldindata.org/energy#citation. [Accessed 5 December 2020].

[22] A. Bitong, “The Next Space Race: Farming Solar Power in the Cosmos,” 27 June 2016. [Online]. Available: http://www.takepart.com/feature/2016/06/27/solar-farms. [Accessed 5 December 2020].

[23] M. Prado, “Asteroid Mining,” 2020. [Online]. Available: https://www.permanent.com/asteroid-mining.html. [Accessed 8 December 2020].

[24] European Space Agency, “ESA,” 2020. [Online]. Available: https://www.esa.int/. [Accessed 8 December 2020].

[25] A. Steindl and H. Troger, Is the Sky-Hook Configuration Stable? Nonlinear Dynamics, vol. 40, Vienna: Institute for Mechanics, Vienna University of Technology, 2005.

[26] V. V. Glazkov, O. A. Sinkevich and G. B. Shmelkov, “Universal Rocket Space Engine and solving the problem of space debris,” Journal of Physics. Conference Series, vol. 1370, 2019