Part 2 of 2 Parts (Please read Part 1 first)
Nanoracks is just in the first stages of research and planning on how to repurpose space junk. It is considering the use of robots that “look like a hand or a snake” carried in the MLS rocket to cut up fuel tanks and weld them into new configurations. Manber said, “You can have robots spring to life and they can put up walls or they can take satellites and deploy them or they can operate labs.” Nanoracks has also partnered with a Canadian robotics company named MDA Robotics and Automation.
MDA is a Canadian company and is a subsidiary of MacDonald, Dettwiler and Associates Ltd. It specializes in the manufacture of robotic arms and equipment for space applications. It made the Canadarm for the Space Shuttle orbiters and the Canadarm-2 on the International Space Station.
Nanoracks believes that it will be cheaper and safer to build their outposts in space as opposed to building them on the ground and launching them into space. Manber said, “A launch is a dangerous and risky thing technically.… I have a launch tomorrow morning. I'm nervous and I don't know how many launches I've been to.”
Manber has said that currently the upper stages of the Cyclone 4M could not be used for any purpose that would require housing human beings because of the fuel that will be carried in the tank. Yuzhnoye, the company that makes the Cyclone 4M rockets has been working on the creation of “green” fuels that would leave the recycled tanks safe for human habitation.
The current Cyclone 4M upper stages could still be used for purposes that don’t include human use. One possible use would be a fuel depot to support a Mars mission.
Right now, upper stages of rockets either burn up during reentry into the Earth’s atmosphere or are sent into what are called “junkyard orbits.” They add to the estimated thirty-four thousand pieces of space junk that are the size of baseballs or bigger. Stephen Matier is the President and CEO of MLS. He believes that recycling space junk materials in orbit is a good idea. He said, “We've got this stuff up there anyway, so why not take it and reuse it and repurpose it for something that has a second benefit, a second bite at the apple, if you will, that does more science.”
If it proves feasible to recycle space junk, MLS and Nanoracks could reap substantial financial rewards. There would be other companies eager to employ their technology. Matier said, “Having a station that somebody can go to and drop off material or collect material as they're pursuing their mission, you know, that's the way it's going to benefit everybody.”
Manber said that Nanoracks chose MLS for collaboration because the company has “seasoned industry veterans.” The use of the Ukrainian rockets by MLS was also a reason for the choice. The use of a northern latitude launch site would also provide Nanoracks with easy access to different orbits.
MLS received environmental approval from Nova Scotia in June of this year. Matier said that MLS intends to launch its first Cyclone-4M rocket from the new Canso launch facility at the end of 2021 or the first part of 2022.
Part 2 of 2 Parts (Please read Part 1 first)
Part 1 of 2 Parts
I have often blogged about the terrible problem with space junk. There are millions of pieces at many sizes that could threaten satellites. One solution to this problem may be to find a way to recycle the space junk. I recently blogged about some ideas for recycling materials from satellites in geosynchronous orbit to build new satellites. Batteries, cameras and solar panels were also to be recycled. Now there has been a proposal to recycle empty fuel tanks.
Nanoracks is a private space company headquartered in Houston. It was launched to develop products and offers services for the commercial utilization of space. The company hosts a CubeSat Deployer which was developed to deploy CubeSats from the International Space Station. Nanoracks is planning for the construction of a rocket-launching facility on the Eastern Shore of Nova Scotia.
Maritime Launch Services is a private space company headquartered in Nova Scotia, Canada. It is a space transport services company. MLS is a joint venture of three U.S. based firms. One hundred and ten million dollars will be spent by MLS to construct a launch site near the town of Canso, Nova Scotia. It will rely on Ukrainian Cyclone-4M rockets to launch satellites into solar and sun synchronous orbits from Canso.
The Cyclone-M4 rocket was derived from the Tsyklon-4 rocket which was going to be developed as launch vehicle for a planned launch site at the Alcantara Launch Center in Brazil. The cooperative agreement between Ukraine and Brazil was cancelled over concerns about the cost and projected market. MLS announced in 2017 that it was going to use the design of the Tsyklon-4 as the basis for a new rocket called the Cyclone-M4.
The Cyclone-M4 was designed by Yuzhnoye and is being manufactured by Yuzhmash. The cost of development was originally estimated to be around a hundred and fifty million dollars. The rocket is about one hundred and thirty feet tall and thirteen feet in diameter. It has two stages. It can carry anywhere between two thousand pounds to eleven thousand pounds of payload depending on the altitude of the orbit and the orbital orientation. The first stage weighs about a million pounds including the fuel which is liquid oxygen and a highly refined form of kerosene similar to jet fuel. The second stage weighs about fifty-five thousand pounds including fuel which is nitrogen tetroxide and unsymmetrical dimethylhydrazine.
MLS and Nanoracks have signed a contract to collaborate on the repurposing of upper stages of the MLS Cyclone-4M rockets. Nanoracks has been researching ways to recycle space junk to construction what it refers to as “outposts” around the solar systems. The research has been supported by NASA.
The outposts envisioned by Nanoracks include hotels, research facilities, fuel depots and storage centers. Jeffrey Manber is the CEO of Nanoracks. He said, “There's lots of things that you can be doing with the upper stages and our core belief at Nanoracks is you don't waste something in space — it's too precious.”
Please read Part 2
A few days ago, U.S. Vice President Mike Pence spoke during the opening session of the International Astronautical Congress (IAC) in Washington, D.C. Pence is the chairman of the White House’s National Space Council. More than six thousand people registered for the event and many of them had to stand in line for security checks to get into the opening ceremony.
During his speech, Pence talked about the Trump administration’s plans to send astronauts back to the Moon and promote space commerce in the present. He also spoke about private property rights with respect to space resources. Pence emphasized the need for international space cooperation in his official welcome address to the IAC.
The main focus of Pence’s presentation was the NASA Artemis program to send the first woman and the next man to the Moon by 2024. After that, NASA will be looking at Mars for future missions. Pence said, “We are well on our way to making NASA’s ‘moon to Mars’ mission a reality.”
Pence specifically praised astronauts Christina Koch and Jessica Meir who just took the first all-female spacewalk last week from the International Space Station. He also praised Japan’s decision to join the NASA Artemis Moon program. He mentioned that European nations were also interested in the Artemis program and were discussing their participation. He said, “To be clear, our vision is to be the leader amongst freedom-loving nations on the adventure into the great unknown.”
Pence made a point of saying that the U.S. would continue to observe the terms of international agreements on space activities. This was presumed to refer to the Outer Space Treaty (OST). The OST states explicitly that no one can make a claim of sovereignty on the Moon or other celestial bodies. Pence went on to say that partners of the U.S. in the exploration and exploitation of space should respect private ownership in space. The issue of private party ownership rights in space is far from settled in space law.
Pence said, “As more nations gain the ability to explore space and develop places beyond Earth’s atmosphere, we must also ensure that we carry into space our shared commitment to freedom, the rule of law and private property. The long-term exploration and development of the moon, Mars and other celestial bodies will require the use of resources found in outer space, including water and minerals. And so we must encourage the responsible commercial use of these resources.”
Pence hinted that the U.S. is in the process of developing new policies with respect to the use of space resources. He said, “We will use all available legal and diplomatic means to create a stable and orderly space environment that drives opportunity, creates prosperity and ensures our security on Earth into the vast expanse of space.”
Speaking about security, Pence mentioned the Trump administration’s work to create a Space Fouce. This would be the sixth branch of the U.S. armed forces. He said, “Soon it will be a reality, and the Space Force will be a vanguard to defending our nation, defending our freedom, and defending the rights of all freedom-loving nations in the vast expanse of space.”
Commercial firms are focusing increased attention on space resources. This includes potentially valuable metals and minerals. It also refers to water on the Moon and asteroids that could be converted to drinking water for astronauts or broken down to create fuel for spacecraft.
Blue Origin is one of the companies that is receiving NASA funding in order to develop technologies for processing space resources. Jeff Bezos picked up an Excellence in Industry Award for Blue Origin at the IAC meeting. The crew of Apollo 11 were the recipients of and IAC World Space Award.
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.
Part 2 of 3 Parts (Please read Part 1 first)
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.”
Please read Part 3
Part 1 of 3 Parts
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.
Part 1 of 2 Parts
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.”
Part 2 of 3 Parts (Please read Part 2)
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