Part 3 of 3 Parts (Please read Parts 1 and 2 first)
The Growth-Adapted Tensegrity Structures project utilizes the mathematics of tensegrity systems which will be used in the design of the Skyframe habitats. The tensegrity math was developed by Dr. Robert Sheldon who became the Skyframe Chief Scientist in 2013. This project was funded by the NASA Innovative Advanced Concepts program and led by Texas A&M researchers. The project calls for beginning with a small space station and slowly expanding it into a rotating habitat that will be capable of supporting up to eight thousand people in simulated gravity equal to normal Earth gravity.
One major question with respect to the construction of huge rotating space habitats with room for thousands of people is where the construction materials will come from. Some of the conference attendees suggested that construction materials could be obtained from the surface of the Moon or from near-Earth asteroids. Water is often mentioned as a critical resource for space construction projects for the astronauts to drink. Using solar power for electrolysis, water can be broken down to oxygen for breathing as well as providing hydrogen and oxygen for use as fuel.
Dennis Wingo is the CEO of Skycorp, Inc. whose mission statement says the purpose of the company is “to fundamentally transform the spacecraft industry, utilizing orbital assembly process, electric propulsion, and modular construction, to create applications unthinkable before.” He said that the Moon could supply regolith for building materials, helium-3 to fuel fusion reactors for power, and sapphire for semiconductor substrates and high-quality glass.
While many technical challenges to the exploration and exploitation of space have been solved in the fifty years since O’Neill published the High Frontier, there are many challenges that still confront the creation of space habitats. Chris Lewiki is the co-founder to ConsenSys Space. ConsenSys is a venture studio focused on Etherium cryptocurrency. They acquired Planetary Resources, an asteroid mining venture in 2018. Lewiki said, “We haven’t figured out how to privately or publicly finance long-term, high-risk, capital-intense projects.” This problem was highlighted by the financial problems at Planetary Resources which led to their acquisition by ConsenSys.
Lewiki has not yet revealed ConsenSys business plans for space projects but he suggested that the blockchain system of cryptocurrencies such as Etherium might be useful in funding space ventures. He said, “What’s interesting there is the way that it allows you to connect disparate things in a more understandable way, in a more traceable way so that you could, for example, create a financial investment share community around a shared project.”
Phil Metzger is a planetary scientist with the Florida Space Institute at the University of Central Florida. He emphasized that artificial intelligence will be critical in humanities movement into space. He said, “We can’t leverage ourselves more if we have to do everything, if we have to control all of the machines. The key to making this all work is artificial intelligence and machine learning — having smarter machines so that we have more machines per person managing them.”
Only time will tell if any of these projects for rotating space habitats will come to fruition, but the enthusiasm of the conference attendees was undeniable.
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There are a number of billionaires these days who are very interested in the exploration and exploitation of space and have founded their own companies in the rapidly growing space industry. These individuals include Jeff Bezos who founded of Blue Origins, Elon Musk who founded SpaceX, and Richard Branson who founded Virgin Galactic. The late Paul Allen who founded Vulcan was also a space entrepreneur.
These new companies and many other competitors have driven down the cost of sending payloads to orbit to the point where considerations of space habits no longer sound like science fiction. And, the founders of many of these companies are very interested in the possibility of space habitats.
There are other rich individuals outside the U.S. who are aggressive actors in the space industry including a Russian oligarch named Yuri Milner who has proposed using many tiny probes to carry out a mission to another star.
Alan Globus has been an advocate for space settlements for decades. He spent many years at the NASA Ames Research Center. He has estimated that it would require about sixty launches of the yet-to-be-built SpaceX Super Heavy rocket to place the equipment and materials in orbit required to construct a 360-foot diameter rotating space station. The project is called Kalpana 2. The SpaceX Super Heavy rocket will be able to carry a payload of two hundred and twenty thousand pounds into
In the 1970s, NASA was estimating thousands of launched to construct the Stanford Torus space station in low Earth orbit. The Stanford Torus would have been about six thousand feet in diameter. The more modest proposals outlined at the conference are much more realistic.
Globus suggests that a smaller Von Neuman rotating space station might be an even better starting project. He said, “A space hotel has requirements fairly similar to a space settlement. So you can build a small hotel, which you could do with a single launch, and you could start gaining revenue. If your small hotel is successful, you build a bigger one.”
Globus also said, “If you take the most optimistic rumors floating around about the [SpaceX] Starship and so forth and so on, and you assume that the cost of the stuff and construction is no greater than the cost of transportation — which is a big if, by the way — then you can argue that it’d cost a couple about $5 million to move in.”
A group called Space Decentral says that “We are building a decentralized space program, connecting thousands of engineers, scientists, and future astronauts, to devise and fund next-generation space initiatives.” They presented a plan for a multi-industry space outpost which was designed by architect Suzi Bianco from the University of Houston.
Skyframe Research says that its goal is to develop and “deploy deep space rotating habitats with extended capability for cyclical growth.” They will use radiation shielding based on a layered water design. Andrew Longman made the presentation. He said, “We need to find an evolutionary approach so we can make it affordable.”
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Fifty years ago, a Princeton physicist named Gerald O’Neill tasked his students with working on a plan for space habitats. Giant cylinders were designed that would rotate to provide gravity. Giant mirrors would reflect sunlight into the cylinders with day and night cycles. A few years after the student project, a book titled The High Frontier was published by O’Neill that laid out details of the work of O’Neill and his students. Many people including Jeff Bezos were inspired to become involved in the exploration and exploitation of space by the ideas in The High Frontier.
Now the California-based Space Studies Institute (SSI) is reconsidering O’Neill’s vision in order to update it for the Twenty First Century. The Space Studies Institute was founded in 1977 by O’Neill with the “hope of opening the vast wealth of space to humanity.” The purpose of the Institute is to “open the energy and material resources of space for human settlement within our lifetime.”
Edward Wright is a senior researcher at the Institute. He said, “The fact is, a lot has changed in the last half-century” at a two-day conference presented by the Institute at Seattle’s Museum of Flight.
Space industry experts and entrepreneurs attended the conference to review concepts and designs that have been stimulated by the idea of the O’Neill space habitats. There is a great deal of interest in the space industry and the U.S. government in building a space station to orbit the Moon that would be called the Lunar Gateway. In addition, the U.S. Artemis project is dedicated to returning astronauts to the Moon by 2024 in order to begin building a permanent settlement there.
A major goal of the Institute is to consider strategies that could turn O’Neill’s vision of huge enclosed self-contained space habitats from outdated fantasies to economically viable enterprises. John Blincow is the current president of the Gateway Foundation. He said “The biggest challenge for all of us in this room … is not engineering. We’ve got brilliant engineers here. It’s economics.” The mission of the Foundation is “to build the first spaceport. Our plan includes the development of a robust space construction industry, the first artificial gravity space station and, finally, the Lunar Gateway.”
The Foundation is working on the design and funding for a Von Braun Rotating Space Station. This is basically a ring-shaped space station that rotates fast enough to simulate gravity. In the case of the Foundation version, the ring would have a diameter of six hundred and twenty-five feet. The plan calls for the accommodation of as many as four hundred permanent residents and will offer amenities including restaurants, movie theaters and sports facilities.
It has been estimated that a rotating space station would need to be over six hundred feet in diameter in order for the Coriolis forces not to cause problems for human beings aboard the habitat. The design of the Lunar Gateway would be just big enough to satisfy this requirement.
The estimated cost would be around seventy billion dollars, says Blincow. Seventy billion dollars is a lot of money. However, it has been pointed out that the International Space Station cost about a hundred billion dollars and it has the volume of a six-bedroom house. There are billionaires in the U.S. who could fund the entire Foundation project out of their own pocket.
Please read Part 2
Made in Space is a startup based in Mountain View, California. For the past nine years, the company has been working closely with NASA to develop technology that will allow the 3D printing of objects in space and then assemble parts using robots. From its beginnings in 2010,. MIS has had some impressive successes. In 2015, MIS sent a 3D printer to the International Space Station. It has been working since that time on the improvement of their microgravity 3D printers. It has a seventy million dollar contract with NASA to construct ten-meter solar arrays in orbit. The Archinaut One is a small satellite with a 3-D printer and a robotic arm. Once it reaches orbit in 2022, the Archinaut One will 3D print components and then assemble them into the power system.
Jim Bridenstine is the NASA administrator. During a tour of MIS in late August, he told a SpaceNews reporter that “As an agency, we have always had constraints when it comes to accessing space. One of the major constraints is the size of a fairing of a rocket and the weight of the things that we launch into space and the amount of materials. All of these constraints drive solutions that are not optimum and cost more.”
The possibility of 3D printing things in space has many far reaching implications. According to Bridenstine, such a capability could help NASA in future space missions including their intention to land a man and woman on the southside of the Moon by 2024. Bridenstine says that the ability to 3D print components in space is “transformational."
Andrew Rush is the president and CEO of MIS. He issued a press release which announced the new contract with NASA last July. The press release said, “Autonomous, robotic manufacturing, and assembly will reshape the landscape of space exploration and space infrastructure and we are taking a monumental step towards that future. Through our partnership with NASA, we will build a space-optimized asset on-orbit, for the first time, that will prove the efficacy of this technology, reduce the risk posture, and manifest new opportunities for in space manufacturing.”
The Gateway Earth project which I covered in a recent post, propose the construction of a space station about a hundred miles above geosynchronous orbit. The purpose of the station would be to shepherd geosynchronous satellites which are not longer useful into a parking orbit above the geosynchronous orbit. Once move into the higher orbit, the old satellite would be taken apart. Batteries, cameras and solar panels could be recycled. The shells of the satellites could be ground up to make a feed stock for 3D printers such as those being developed by MIS.
Tethers Unlimited are working on a eight armed construction robot which will be able to 3D print structural members to be assembled into lattices. These lattices could be used to provide support for geosynchronous satellites. This will help solve the problem of crowding in geosynchronous orbit.
The OpenLuna Foundation (OLF) is a San Francisco nonprofit venture that has a plan to create a settlement on the Moon for a cost of around five billion dollars. For the past five years, the OLF has kept a low profile but now they are being more public about their plan.
Silicon Valley venture capitalist Steve Jurvetson provided the initial funding for the nonprofit foundation. He said in a tweet, “At $5B, it’s not only achievable within current NASA budgets, it offers the tantalizing possibility that a single passionate individual could fund the entire program as their legacy!”
Bloomberg News recently published a report about the OLF. OLF currently has about five million dollars to pursue its goals. It intends to raise additional funds for hardware and policy initiatives.
It may sound a little over-optimistic to think that a nonprofit could lead efforts for a lunar settlement. It has taken major national governments to fund existing space programs. While billionaires like Elon Musk and Jeff Bezos have launched major for-profit space ventures, neither of them is involved with the OLF. However, Jurvetson rescued Musk’s SpaceX when it almost went bankrupt in 2008 and he continues to provide major support for SpaceX. Will Marshall and Robbie Schingler are cofounders of the Planet satellite venture. They are also a part of the OLF campaign as is Kate Schingler, Robbie’s wife. Chris Hadfield is a retired Canadian astronaut who has served missions on the International Space Station. Pete Worden is the former director of NASA’s Ames Research Center and the current chairman of the Breakthrough Prize Foundation. Both of them are part of the OLF team.
The OLF was born from a weekend retreat that was held by Steve Jurvetson in 2014. Since then, the OLF has been discussing the potential for small scale unmanned missions that could pave the way for a manned lunar base. Parallel to efforts of the OLF, the White House and -NASA have been drawing up plans for a multibillion dollar project to put astronauts on the Moon by 2024. From the coverage in Bloomberg News, it would appear that the OLF does not think that government space projects and private space ventures need be mutually exclusive.
Chelsa Robinson is the chief of operations and staff for the OLF. She has been quoted as saying that settlement,” “Our highest ambition is catalyzing and enabling a peaceful and cooperative lunar settlement. At this time when there are so many commercial and government actors advancing their efforts on the moon, we are excited to demonstrate a civic approach to participation.”
The plan of the OLF is similar to the European Space agency’s “Moon Village” concept. Both call for various groups involved in lunar projects to coordinate efforts to build settlements on the Moon.
Jeff Bezo has also talked about building a city at the Moon’s south pole with robotic construction equipment. He has obviously been keeping up with the OLF plans. He used the term “Moon Base Alpha” in 2017. This phrase was used by the OLF back in 2014. Musk said, “We should have a lunar base by now,” Musk said at the time. “What the hell is going on?”
It will certainly require more than the five million dollars that the OLF has on hand to make significant progress in setting up a permanent base on the Moon. However, considering the powerful players aligned with the OLF, it may indeed play a role.
Part 2 of 2 Parts (Please read Part 1 first)
The Gateway Earth station could repair, repurpose or recycle dead satellites and space debris. The materials resulting from this activity could be uses as construction materials for future spacecraft or bases on the moon. This harvesting of materials would reduce space junk and would not cost anything to launch because they are already in orbit. These recycled materials could also produce income to support the Gateway Earth station.
Research indicates a space station in an orbit one hundred miles above the protected zone in GEO would have access to the entire GEO. Satellites could be captured and taken to the station by a fleet of drones. They could be either recycled or repaired. It is estimated that such activities could generate over eight billion dollars a year. However, the international space laws mentioned above are outdated and would require extensive revision in order for this to happen. Fortunately, the United Nation is already working on this problem with input from the Gateway Earth Development Group.
One use for the shells of the dead satellites could be to grind them down into powder and use the powder to 3-D print radiation shielding for Gateway Earth. Research shows that the type of solar panels used in satellites only lose about a quarter of their efficiency in fifteen years. This means that panels on old satellites could be removed and used to power Gateway Earth.
Many excellent cameras have been sent into space on satellites. If these could be recovered from defunct satellites at Gateway Earth, they could be repurposed to watch the sky for asteroids that might collide with the Earth. Currently there are about four thousand functional satellites in Earth Orbit. Thousand more are about to be launched to LEO. There are also plans to put another one hundred and fifty satellites in GEO. It would be very useful to have Gateway Earth in a high orbit to manage all these satellites.
There are plans to expand Gateway Earth into a space hotel to generate additional revenue. Future enhancements include satellite and spacecraft construction facility. It could also serve as a spacecraft refueling facility for space missions beyond Earth orbit.
Tethers Unlimited is working on a construction spider robot with eight legs. Four for climbing around on space structures and four for construction. The robot will carry a spool of construction material that could be used to construct space lattices. Having space lattices in GEO would be very useful. Right now, each satellite that goes to GEO has to go alone and find a clear path around the Earth that does not interfere with other satellites. With huge lattices constructed by robots, satellites could be sent to GEO and mounted on the lattice saving orbital space and concentrating the satellites to make them easier to service. The construction material to construct the space lattice could be provided by ground up satellite shells.
Gateway Earth has the potential to be a major step in the long-term proper use of GEO.
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Last week I posted an essay about a new system developed by Tethers Unlimited to deorbit small satellites by unreeling a strip of electroconductive tape at the end of a satellite’s life. This system is under development to help remove small dead satellites in a matter of weeks rather than the many months that are now required. There are tens of thousand pieces of debris from launches and dead satellites now being tracked in Earth orbit. There are over a million pieces too small for radar to spot also in Earth orbit. If this debris keeps piling up, it may become impossible to launch payloads into orbit or beyond. It is critical that we find a way to clean up this orbital debris if we want to continue to explore and exploit space.
The Gateway Earth Development Group is a collection of academics associated with universities around the world. They are working on plans for a space station called Gateway Earth that would have facilities to recycle old satellites and other space junk. They hope to be able to have such a station operational by 2050.
There are two main orbits in use around the Earth. The Low Earth Orbit or LEO extends from about one hundred and twenty-five miles above the Earth to about six hundred and twenty miles. The International Space Station obits the Earth every ninety minutes in LEO. There are thousands of satellites in LEO.
LEO is very crowded and there is a danger of collisions which could result in a shower of debris that could trigger a cascade of showers as further collisions occurred. Technology (such as the Terminator Tape of Tethers Unlimited) is being developed to reduce debris and old satellites in LEO.
Geostationary Earth Orbit or GEO is about twenty-three thousand miles above the Earth. At this altitude, satellites will remain in position over one spot on the Earth as the Earth rotates. This orbit is an excellent place for weather and communication satellites.
When a satellite in GEO reached the end of its operational lifetime, the operators try to move it to a higher orbit two hundred to two hundred and fifty miles above the protected zone where GEO satellites operate. About eighty percent of dead GEO satellites actual make it up to the higher orbit. It is the twenty percent that remain in the protected zone that are a major problem that requires a solution. A recycling space station could be that solution.
The higher orbit is like an abandoned junkyard. Flashes of light are sometimes seen in this orbit which are likely collisions between dead satellites where unused fuel or old batteries explode. There is a danger that dead satellites and collision debris could fall back into the protected zone and threaten operational satellites.
Unfortunately, international space law is not helpful with respect to dealing with dead satellites in GEO and in the graveyard orbit. Dead or out of control satellites cannot be touched without permission of the owners even if those satellites threaten expensive functional satellites.
I have blogged before about all the debris orbiting the Earth left over from space launches. It is estimated that there are more than one hundred million pieces of debris that are less than 1 centimeter in size. They are too small to track with radar but are big enough to cause serious damage to a space craft because they are traveling so fast. The United States Strategic Command tracks about eighteen thousand pieces of debris that are bigger than four inches. If fact, if the debris keeps piling up, it may become impossible to safely launch a payload into Earth orbit or beyond. A variety of systems have been proposed for removing debris from orbit.
Tethers Unlimited (TU) is located in Bothell, WA. In collaboration with TriSept Corp., Millennium Space Systems and Rocket Lab, they are going to test a new system to remove satellites from orbit which are no longer operational. The system is called Terminator Tape. It involves incorporating a module into a satellite which can unwind a strip of electrically conductive tape when the satellite is no longer in use.
TU explained the system in an online post that said, “This tape will significantly increase the aerodynamic cross-section of the satellite, enhancing the drag it experiences due to neutral particles. In addition, the motion of this tape across the Earth’s magnetic field will induce a voltage along the tape. This voltage will drive a current to flow up the tape, with electrons collected from the conducting ionospheric plasma at the top of the tape and ions collected at the bottom. This current will induce a ‘passive electrodynamic’ drag force on the tape.”
It is believed that the increased drag on the satellite from the tape will significantly cut down the time that it takes to drag the satellite down to burn up in the atmosphere. TU has already sent its Terminator Tape module into Earth orbit in several small satellites. However, the Dragracer satellite mission due for launch next year should be the best test for the Tape. There will be a control experiment included in the test.
Millennium Space Systems is a Boeing subsidiary located in California. It will construct and operate the fifty-five pound Raptor-class satellite for the Tape test. TriSept is a company located in Virginia. They will handle launch integration and mission management services for the test. And, finally, Rocket Lab will include Dragracer in a ride share on its Electron rocket that will be launched from New Zealand in early 2020.
When the satellite reaches orbit, it will divide into two payloads. One of them will initiate the deployment of the Tape and the other will experience just atmospheric drag without the Tape. Mission managers estimate that it will take two to four weeks for the payload with the Tape deployed to deorbit while the other payload will take from eight to twelve months to descend from orbit.
Mike Scardera is vice president of advanced concepts for Millennium Space Systems. He said, “The Dragracer mission is all about providing an affordable, effective and scalable solution to the orbital debris challenge facing the LEO small-satellite market and the global space. It is the first in a series of critical project missions we expect to launch with TriSept.”
The president and CEO of TriSept, Rob Spicer, said that the Dragracer test will demonstrate a new creative solution to the problem of dead small satellites that are piling up in orbit. Hopefully, some of the small satellites that will be launched in the future will include the Tape deorbiting system developed by Tethers Unlimited.
One of the more fantastic ideas for getting into space is the space elevator. The basic idea is that a super strong cable reaches from the Earth’s surface to a huge counterweight that is beyond the twenty-three thousand miles geosynchronous orbit. Vehicles like elevator cars would climb up and down the cable lowering the cost of sending things to and from orbit by several orders of magnitude.
The idea was first proposed in 1895 by Russian scientist Konstantin Tsiolkovsky. An old comic published in the U.S. in the 1950s depicted a man in a space suit climbing a ladder into space. American engineer Jerome Pearson published the first technical description of a space elevator in 1975. The concept of a space elevator came to popular media with two novels, both published in 1979. These novels were The Fountains of Paradise by Arthur C. Clark and The Web Between the Worlds by Charles Sheffield. Since then there have many mentions of space elevators in popular novels, comics, movies and television shows.
The main technical problems with constructing a space elevator are buckling, dynamic stability and strength. Engineers believe that a satellite in geosynchronous attached to the cable could solve the problems of buckling and dynamic stability. The unresolved problem with strength lies finding a material that has the incredible strength necessary to withstand the enormous strain that such a construct would endure. After a hundred and twenty-five years, it now appears that such a material may be available.
The cable for the space elevator would have to have a tensile strength of seven gigapascals. One pascal is defined as about one newton per square meter. One newton is defined as the amount of force necessary to accelerate one kilogram of material at the rate of one meter per second squared. Peason suggested that perfect crystals of graphite might have the strength necessary.
Chinese scientists at Tsinghua University have announced the development and patent of a carbon nanotube fiber with a tensile strength of eighty gigapascals. This is over ten times stronger than theoretical studies say is needed to build a space elevator. Part of their research has been published in the journal Nature Nanotechnology. The Chinese scientists said, “in great demand in many high-end fields such as sports equipment, ballistic armor, aeronautics, astronautics and even space elevators”.
Nicola Pugno is a professor of solid and structural mechanics at the University of Trento in Italy. He thinks that the new fiber developed by the Chinese scientists is promising. He said, “Having a strong mega-cable and maintaining its strength and flaw tolerance is the biggest challenge. The Nature Nano report [from the Tsinghua team] is a key step towards the solution … thus, never say never.”
One concern that I have about the creation of a space elevator is that it would be very vulnerable. If the base was destroyed, the counterweight would yank the cable into space. This would wreak havoc with the satellite to which the cable was attached. A missile or a bomb in one of the elevator cars could break the cable above the surface of the Earth. Any length of cable that was below the cut would fall back to Earth, wrapping itself around the equator causing devastation and tsunamis. If the break was above the satellite in geosynchronous orbit, the satellite would be yanked down to Earth. There would be enough cable to wrap almost all the way around the Earth. As useful as a space elevator might be, I am afraid that it would be much too dangerous to ever be constructed.
Part 3 of 3 Parts (Please read Part 1 and Part 2 first)
One big stumbling block for the Interstellar Probe project is the fact that best heat shield ever used by a NASA probe is only able to protect a probe that comes within four million miles of the Sun. The Interstellar Probe would have to come within two million miles of the Sun in order to make best use of the gravity boost.
Nicky Fox is the director of NASA’s heliophysics division. She says, “There is a moment for every big mission, almost an ‘aha’ moment, when the technology is ready and you’ve got a plan and it makes sense and is going to answer the science questions.” The heat shield problem is standing in the way of satisfaction with the Interstellar Probe plan.
There is another big question that looms with respect to the Interstellar Probe mission that goes beyond technology and politics. By 2050 deadline projected for the Interstellar Probe to reach its objective, the United Nations’ Intergovernmental Panel on Climate Change estimates that the global average temperature will be two degrees Celsius above the average temperature in pre-industrial times. Unless the world embarks on a “moon-shot” to curb carbon emissions, in 2050 many of the world’s major cities will be under several feet of water due to sea level rise or they will be experiencing temperatures that will make them uninhabitable. Unfortunately, major countries have not done enough to curb their carbon emissions.
Mandt believes that the Interstellar Probe mission might be helpful in inspiring the U.S. and the world to also seriously consider putting major resources into a multigenerational project such as mitigating climate change. She said, “This would be an example of a large group of people working together on something multigenerational. Which is the same thing we need with climate change.”
She has pointed out that members of the team working on the Interstellar Probe mission range from recent graduates from graduate school programs to people who are on the verge of retirement. At least eight different countries have contributed members of the team. The team includes engineers, astronomers, planetary scientists and a particle physicist.
Last year, Mandt invited Janet Vertesi of Princeton to advise them on best organizational principles. Vertesi has carried out ethnographic studies of possible teams for astronauts who will share a spacecraft. This is the first known incident where a sociologist has been involved in the development of a NASA space mission.
Vertesi said that her job for the Interstellar Probe project was to remind them of the human side of such missions. How will the team handle conflicts? Where should the data be stored? How does the team recruit diverse members to properly represent the nations who will launch the probe? She said. “We’re testing out this notion that you can actually plan a mission up front to achieve certain social objectives, too.”
Vertesi says that it is good feeling to be involved in such an inherently long-term optimistic project given all the problems that bedevil the world today. Scientists will dedicate their careers to a project that will outlive them. She adds, these people just can’t wait for the future to come.”
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In order to achieve the maximum velocity possible to travel beyond the Solar System, a really powerful rocket will be required. NASA hopes to have its powerful Space Launch System (SLS) ready by 2021. It is capable of twice the thrust of the most power current launch system. The SLS would launch from Earth at about nine miles a second. It would loop around Jupiter and then plunge back into the Solar System to get a gravity boost from the Sun. Skimming through the outer atmosphere of the Sun, it would fire a second rocket which would boost its speed to around sixty miles a second. At this speed, it should reach the heliopause in about ten years.
The team working on the McNutt plan hopes that they will be able to route the probe past Uranus, Neptune or a body in Kuiper Belt know as Quaoar. Kathy Mandt is a planetary scientist who hopes that good use can be made of the time the Interstellar Probe spends in the Solar System. It might also be useful for improving the search for exoplanets. This could be accomplished by looking back at planets in the Solar System with the same equipment that is currently being used to look for exoplanets. When the probe crosses the heliopause, it can take samples of dust and particles which will aid in understanding the heliosphere and the materials that formed our Solar System.
Once beyond the protective bubble of the heliosphere, it will be able to investigate phenomena that are obscured by the heliosphere such as cosmic rays from exploding stars, light from the afterglow of the big bang, disks of debris that are forming planets around young stars and other interstellar objects and processes.
So far, the McNutt Interstellar Probe only exists as a PowerPoint Presentation. His team has received funding of around seven hundred thousand dollars from NASA for concept studies. Currently they are waiting to find out whether NASA will provide an additional six and a half million dollars over the next three years. This would permit them to draft a more detailed plan for scientific studies and a mission design document.
The critical moment for the Interstellar Probe project will arrive in 2023. The National Academies of Sciences, Engineering and Medicine will publish their next decadal survey for solar and space physics. These assessments are conducted every ten years under request from Congress and NASA. They are considered to be the official consensus for U.S. space science goals. They will guide NASA budgeting for the next ten years.
Richard Mewaldt is a Caltech physicist who served as chair for the solar and heliospheric physics panel during the most recent decadal survey which was published in 2013. He said, with respect to the Interstellar Probe, “It was always something we couldn’t do immediately, but set aside maybe for the future.” In the 2013 decadal document, advanced planning for an interstellar probe was ranked as the eighth among nine imperatives for NASA.
NASA has a heliophysics division which would be responsible for overseeing any interstellar missions. It receives less funding than any other NASA science division. It might help launch the Interstellar Probe mission if they could interest the planetary sciences division at NASA in flyby missions to the outer planets and/or the Kuiper Belt object. Unfortunately, the different NASA divisions are kept well separated and it is difficult to obtain funds from multiple NASA division for a single mission.
Please read Part 3 next
Part 1 of 3 Parts
For the most part, I have blogged about space around the Earth. Occasionally I have ventured out into the Solar System. Very rarely, I have written about missions beyond our Solar System. Today I am going to blog about a such a mission.
Ralph McNutt works at the Johns Hopkins University of Applied Physics Laboratory. Now sixty-five, he has been interested in interstellar travel since he was a teenager. He is currently drafting a plan that would send a probe ninety-three billion miles into interstellar space. This is about one thousand times the distance between the Sun and the Earth which is referred to as one astronomical unit. The probe would explore the conditions beyond the Solar System. The probe would take about fifty years to reach its destination. It is likely that everyone involved in launching the probe will be dead by the time it achieved its objective.
McNutt and his team hope to be chosen when U.S. space scientists release a list of their top research priorities. In order to get their mission on the agenda, they must convince their colleagues that the goal of the mission is scientifically valuable. Of course, it will have to be politically viable in its competitions with many research worthy topics on the Earth and in the Solar System.
Our Sun is in a minor arm of the Milky Way galaxy. The Milky way is about one hundred thousand light years across. The Earth is about twenty-five thousand light years from the center of the Milky Way which, about half the way to the rim. The Earth is currently traveling about half a million miles per hour. It is hit by gusts of gas and dust and pounded by highly energetic particles whose origins are unknown. The surface of the Earth is shielded from this rain of gas, dust and particles by what is called the “heliosphere.” This is a stream of charged particles called the solar wind which streams out past all the planets to the very edge of the Solar System. Out beyond the Solar System, there is a region known as the “heliopause.” This is the buffer zone between the solar wind and the ocean of dust and gas in interstellar space. It is the boundary between our Solar System and the interstellar environment.
Only two Earth probes have ever reached the heliopause while still functioning. The two probes were referred to as Voyagers. They were launched in 1977 and it took over thirty-five years for them to reach the boundary. Other probes have traveled out of the Solar System, but they had stopped functioning by the time they reached the heliopause. Some of the instruments on the Voyager probes have failed and their radio transmissions have become fainter and fainter.
Voyager 1, the most distant object ever built by humanity is now one hundred and forty-five astronomical units. At the rate that it is traveling, it will take two hundred and eighty-three years to make it to the region targeted by McNutt.
Please read Part 2 next
NASA has just announced that it is sending a lander to Titan, a moon of Saturn. The lander will carry a robot helicopter to explore Titan. The mission is called Dragonfly. It is part of NASA’s New Frontiers program which is dedicated to high-priority solar system science projects. Current New Frontiers missions include Juno which is a mission to Jupiter, New Horizons which is currently flying through the Kuiper Belt and OSIRIS-Rex which is orbiting the small asteroid named Bennu.
Dragonfly includes a quadcopter. It has four pairs of coaxial propellers which are each mounted to the corners of the thirty feet long lander. The plan is for it to land and then make a series of five-mile hops so it can carry out experiments at different locations. It will take pictures and samples of the air and surface materials to examine their chemical composition. It will also take meteorological and seismological measurements at each location. The main goal of the mission is to determine whether there are organic molecules on Titan that could be the basis of some kind of life.
Saturn is over eighty-six billion miles from Earth. Titan is so cold that if there is water on the surface, it will be as hard as granite on Earth. Titan has a atmosphere fifty percent thicker than Earth which is compose mostly of nitrogen. The Cassini spacecraft orbited Titan and took many images and readings. Some of the surface features captured by Cassini include dunes composed of hydrocarbon sand, cryovolcanoes and even evidence of an ocean of liquid water under the surface. Cassini also found huge lakes of liquid methane and ethane close to the north pole. Radar images of the landscape revealed hills and rivers that flow into the lakes. This suggests that methane on Titan behaves in a way that resembles water on Earth. It has a similar cycle composed of evaporation, movement as vapor in the atmosphere, rain and large pools of liquid on the ground. Although the temperature on Titan is around -290° Fahrenheit, the methane cycle and lots of organic molecules may be involved in complex prebiotic chemistry reactions.
The Dragonfly mission is scheduled for a 2026 launch date assuming that the hardware for the mission will require about seven years to construct. Much of the instrumentation is based on known and tested designs. The power source will be a common radioisotope thermoelectric generator that uses plutonium to generate electricity. Solar power would not be useful because Titan only gets about one percent of the sunlight that falls on the Earth. The big question is whether or not the propellers will function correctly in the cold atmosphere. On the positive side, the gravity on Titan is only one seventh of the gravity on Earth and the atmosphere of Titan is much denser. This should make it easy to fly around on Titan. What winds there are on Titan are low velocity and should not present a problem. If Dragonfly is launched in 2026, it will not reach Titan until 2034.
The Dragonfly mission as envisioned should last for at least two and a half years. Unfortunately, this will not be enough time for the quadcopter to hop from the landing site near the equator to the huge lakes at the pole.
I have written about Tethers Unlimited (TU) before. They are a private space company located in Bothell, WA. Years ago, when they were founded, tethers were thought to hold great promise for a number of space applications. As time passed, that promise faded and so did the money available for research and development. When I saw a presentation by the head of TU last year, they were diversifying into providing satellite maneuvering thrusters using water for fuel and satellite radios that used software to set the frequency.
NASA has just handed out forty-five million dollars to support three hundred and sixty-three aerospace projects that were proposed by small businesses and research institutions. Each project has been awarded up to a one hundred and twenty-five thousand dollar Phase 1 grants as part of NASA’s Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR). TU was awarded grants for five space technology projects. TU has been granted NASA Phase 1 grants before for such things as in-space construction and 3D printing. Here are brief descriptions of the five new TU projects.
SPIDER: When I was listening to the TU CEO talking about current research projects, he described a machine that could move around on structures in orbit and use a spool of material to create new struts for the structure. I thought to myself that that sounded like a mechanical spider. Soon after that thought occurred to me, he said that they called the construction machine a “Spider”. At TU, SPIDER now stands for Sensing and Positioning in Deep Environments With Retrieval. This new device does not fit the description that I heard at the presentation last year. This new SPIDER is intended to position itself above a lunar crater and take samples while changing position. It was developed to overcome the contamination and stability problems that can occur when a lunar rover is exploring a crater. Phase 1 funding is to support development and design. If NASA funds Phase II, a prototype will be developed and tested.
ARTIE: ARTIE stands for Androgynous Robotic Tool-change Interface. It is intended to supply power and data interface to the connectors on robot arms used in space. Phase I will consist of demonstration of a proof of concept prototype. If NASA grants Phase II for ARTIE, a prototype will be sent into orbit for testing.
VORTEX: VORTEX stands for Venus or Titan Exploration. This is a gimballed pointing mechanism or artificial “wrist” that would be use for Venus and/or Titan explorations as well as satellite operations in other extreme environments. Phase I funds will be to support progress in the design of ARTIE.
HyperBus: The HyperBus Cargo Platform is a palletized system for the transport, emplacement and exchange of hardware at the International Space Station or other orbital platforms. If TU gets to Phase II on this project, funding will be used to develop the concept, construct a prototype and demonstrate the system in the TU laboratory.
RAMP TPS: RAMP TPS stands for Resin Additive Manufacturing Processed Thermal Protection System. Phase I funding will support development of an in-situ cured, additively manufactured, spacecraft heatshield material and process. This device will allow the lost-cost manufacture of heat shields in orbit for re-entry vehicles. TU and Western Washington University will collaborate on the creation of this technology.
Twenty commercial space companies joined NASA representative at a conference last week to discuss the commercial possibilities of the International Space Station. NASA has been planning to use the ISS to support the commercialization of space for some time. Stephanie Schierholz, the lead spokesperson for NASA, said, “We’re here because the International Space Station is now open for business.”
The NASA plan included allowing private astronauts to visit and stay on the ISS, brought to the station by U.S. launch vehicles. It also includes inviting private companies to carry out business activities on the ISS. These activities could include “in-space manufacturing, marketing activities, healthcare research and more.”
NASA presented a five-part plan that it insisted would not conflict with the use of the ISS for government and public sector purposes. It will stimulate creative and varied revenue-generating opportunities for private companies. NASA wants to become just one of many users of the ISS and other low Earth orbit facilities. NASA says that this should benefit the U.S. taxpayers too.
Part 1: NASA has created an ISS Commercial Use Policy. This policy provides a menu of supplies and/or resources that will be available for purchase by private companies. Resources such as crew time, cargo launch and cargo return capabilities are just some of the resources that will be available.
Part 2: Private astronauts can book one or two short duration visits per year beginning in 2020. The missions will have to be privately funded, dedicated commercial space flights. These missions will have to use U.S. spacecraft which will include NASA certified space travel vehicles such as the SpaceX Crew Dragon. NASA will provide pricing for such resources as use of life support, supplies for the private astronauts, physical storage, computer usage and data storage.
Part 3: The forward section of the Harmony Node 2 of the ISS will be the first part of the ISS that will be a commercial destination. Other habitable commercial modules are planned for integration into the ISS in the future. NASA will issue a request for proposals on June 14th. And will select the first customer who will start developing the commercial facilities by the end of this year.
Part 4: NASA is working on a plan to stimulate long-term commercial demand. Space manufacturing and regenerative medicine are the first commercials uses for the ISS being considered. NASA has requested white papers by June 15th and proposals by June 28th.
Part 5: NASA has issued a new white paper that details the minimum needs for commercially viable long-term operations on the ISS.
One of the most import parts of the NASA planning is to significantly reduce the cost of commercial transit to and from the ISS. NASA would also like to see private space companies develop and construct a private space station to eventually replace the ISS when it reaches the end of its operational life.
There are about fifty private companies carrying out projects on the ISS right now. The new announcement is aimed at formalizing and scaling operations over the long term.