Last week I attended the Space Entrepreneurs Epicenter of Space meeting in Marina Park in Kirkland Washington. From their Meetup website, Space Entrepreneurs is ” a physical and virtual network of individuals with ideas on what humanity’s future in and using space should be.” Space Entrepreneurs is for “Those who have an space-related idea and are wondering if they can make it a reality using entrepreneurship or intrapreneurship.” They were founded in February of 2014 in Seattle, WA by Sean McClinton. They hold meetings every month in a variety of formats from casual happy hours to industry-wide events with keynote speakers. They are also a source of information and resources for the space industry.
       The Space Entrepreneurs feel that there has sufficient entry of private firms into space exploration and exploitation to prove that businesses can successfully enter a field that has been the exclusive province of national governments willing to spend huge sums of money to reach space. They say that the current state of the commercial space industry is an excellent environment for entrepreneurship. They have located in Seattle because it is a “coalescing and growing hub” for commercial space activity.
      Their Mission Statement reads “Accelerate the progress humanity is making in creating a space tourism industry, a low-Earth orbit economy, and deep-space economic development and exploration. We will do this by empowering entrepreneurs and intrapreneurs with space-related ideas.” 
Their aims are:
“• Educate those interested in the commercial space industry on how to get involved, what opportunities are available, and what the industry looks like.  
• Connect our members in ways that benefit all parties involved, particularly when it comes to finding partners, co-founders, and investors. 
• Support We support people on the path to finding a model of space entrepreneurship or intrapreneurship that fits their goals, lifestyle, interest and expertise.”
The Space Entrepreneurs can help with finding partners to help start a business. They can help locate investment capital through their relationship with Space Angels Network, the biggest network of space industry investors in the world. Members of Space Entrepreneurs are an excellent sounding board for getting feedback on business ideas. With the rapidly changing private space industry landscape, Space Entrepreneurs can help people keep track of developments with overviews of space industry. When it comes time to put ideas down on paper, Space Entrepreneurs can help startups find the resources they need to create professional plans and presentations. 
       The meeting last Thursday took place in the Gazebo near the water in Kirkland’s Marina Park. It was a balmy evening in a beautiful location. Unfortunately it was also a little noisy. The event attracted a hundred people interested in the private space industry. Drinks and food were served and for the first hour and a half, people wandered around networking. There was a quite a varied mix of people from students to professors, from aerospace workers to journalists, from people starting businesses to people looking for businesses to invest in.
       The Keynote Speaker was Chris Lewicki, the President and Chief Engineer for Planetary Resources, a company dedicated to asteroid mining. He talked about historical examples of the explosive growth of economies in the past like San Francisco and Seattle during the gold rushes. He pointed out that Seattle is once again poised to be ground zero for the rapid growth of a new industry based on private exploration and exploitation of space. However, he cautioned that above all, businesses oriented on space had to be economically viable. His speech was followed by a Q & A session.
       All in all it was an inspiring and encouraging evening for space enthusiasts.  The crowd thinned out and I left after talking to a couple of acquaintances that share my interest in space. It is difficult not to get caught up in the enthusiasm of the moment, but it will be a long hard slog before there is a mature robust and profitable private space industry in Seattle. 
Gazebo in Marina Park, Kirkland, WA:

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        I am attending the Epicenter of Space event in Kirkland Washington on the evening of August 27th. This is a networking meeting for the space industry in the Seattle area. There will be a couple of special speakers including a Managing Partner from the Space Angels Network. I thought I would devote this week’s blog to the Network and some of their projects.
        This is from their website at www.spaceangelsnetwork.com: “We are a professionally managed angel investment group, focused on high-growth aerospace companies.” “Our management team and members are influencers who connect investors, founders, space agencies, and technology buyers with one another.” “We have funded over 25 companies, all of whom are growing. Based on subsequent investment rounds and earnings growth, the estimated growth of our cumulative investments is in excess of 30% per year.” “We are the largest community of space investors and entrepreneurs in the world.”
       Here is a list of some of the companies that SAN has assisted:
Planet Labs is an American private company that aims to create an Earth-imaging satellite network with open data access.
NanoRacks is a private company that provides standard rack-mounted laboratory facilities and microgravity space access to commercial customers at the International Space Station.
XCOR Aerospace is an American private rocket engine and spaceflight development company based at the Mojave Air and Space Port in Mojave, California.
Planetary Resources, Inc. is an American company with the goal of expanding Earth’s natural resource base by developing and deploying the technologies for asteroid mining.
Firefly Space Systems is focused on developing & deploying a dedicated small satellite launcher in the half-metric-ton payload class.
World View Enterprises, Inc. is a private American near-space exploration company that plans to use high-altitude balloons to lift people and scientific payloads twenty miles above earth for the purposes of space tourism, scientific research, and a wide range of other commercial applications.
Deep Space Industries is a private American company in the asteroid mining sector with plans to offer general utility commercial space services beginning in 2016.
Flirtey is the world’s first drone delivery service.
Golden Spike Company aims to democratize access to the moon by providing all-encompassing turnkey access to reasonably-priced lunar missions for countries without their own space programs.
ICON Aircraft is a privately held American aircraft design and production company.
LaserMotive is a U.S. engineering firm developing technologies for efficiently transmitting power via lasers, a form of wireless energy transfer commonly called “laser power beaming”.
OmniEarth is a geoanalytics company developing a satellite constellation to serve its customers with rapid refresh rates and broad coverage.
Orbital Outfitters is a manufacturer of economic, high-performance space and pressure suits for the private and government space industry.
Planetary Power Inc. develops solar and hybrid energy solutions for off-grid and remote operations.
The Rocket Racing League is a racing league that plans to use rocket-powered aircraft to race a closed-circuit air racetrack.
Space Adventures, Ltd. is a private spaceflight company currently providing opportunities for private spaceflight and space tourism.
Zero Gravity Corporation is an American company which operates weightless flights from United States airports catering to both tourists and researchers.
Altius Space Machines is a company that is developing a novel rendezvous and capture technology for uncooperative satellites.
Ansible Space Communications Systems LLC strives to be the world’s leading provider of space communications technologies and services for operators of small satellites.
         I am looking forward to meeting representatives from some of these companies at the Epicenter of Space event Thursday evening. Event details.

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        Launching payloads into Earth orbit or beyond is expensive and difficult. Climbing up out of the deep gravity well of the Earth is not easy. In addition to the pull of gravity, there is also air resistance to consider. Air pressure falls off pretty rapidly above sea  level. At an altitude of ten miles, the air pressure is less than ten percent of the air pressure at sea level. Obviously, if a launch vehicle can take off from a point ten miles or more above sea level, it would significantly reduce the amount of fuel required to fight gravity and air resistance. The higher you could launch, the more fuel you could save. A new company called Thoth Technology has just been granted a patent for a tower that could be used to reduce launch costs by up to thirty percent.
        The basic idea is to construct a tower over twelve miles in height and seven hundred and fifty five feet in diameter. The tower would be constructed with pressurized cylindrical segments which would have a height roughly equal to their diameter. Each segment or cell in the tower would have flywheels that could act as compressors to adjust the pressure in the cell to compensate for lateral forces of winds that would otherwise cause the tower to wobble.
        Astronauts would ascend the tower in a tube up the center of the tower or elevators rigged on the outside of the tower. There would be a short landing and takeoff strip on the top of the tower to permit space planes to take off and land horizontally. These space planes could launch directly into orbit without needed additional stages for boosting. They would be able to refuel and refit at the top of the tower.
        Currently, the cost of launching a pound of payload into space is about ten thousand dollars. Using the Thoth Technology tower to launch may reduce launch costs to around two hundred and thirty dollars a pound.
       The CEO of Thoth Technology says that the reduction in launch costs and the acceleration required would make a takeoff much more like a passenger airplane than taking off in the Space Shuttle. This would reduce the cost, danger and stress to the point where space tourism could become a realistic prospect.
       The idea of using towers to reach space is an old one. Konstantin Tsiolkovsky first published the idea in 1895. He called for a free standing tower that would extend from the surface of the Earth to geosynchronous orbit at about twenty two thousand miles. Since about 1960, designs for space towers have focused on having a counterweight beyond geosynchronous orbit from which the tower would be suspended. The term in common use today is “space elevator.” One of the biggest problems will be finding a material strong enough and light enough to make the space elevator. In the meantime, the Thoth Technology tower is a good place to start building towers to space.

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            The International Space Station has been in the news lately. The first section of the ISS was launched in 1998. The ISS is the largest artificial body in Earth orbit. The ISS consists: “of pressurized modules, external trusses, solar arrays and other components. ISS components have been launched by Russian Proton and Soyuz rockets as well as American Space Shuttles.” The ISS has been continuously inhabited since 2000. “The ISS serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human biology, physics, astronomy, meteorology and other fields.”
       The ISS is a joint project of five different space agencies. U.S. National Aeronautics and Space Administration, the Russian Roscosmos, the Japan Aerospace Exploration Agency, the European Space Agency, and the Canadian Space Agency. The ISS has two sections; the Russian Orbital Segment and the United States Orbital Segment. The U.S. section is shared by many other nations. More than two hundred astronauts from fifteen different countries have visited the ISS.
       China has an extensive space program and has sent astronauts on orbital missions. It is planning to build its own space station called the Tiangong. However, it has never sent astronauts to the ISS. In 2011, the U.S. Congress passed a law banning China from the ISS due to concerns over national security. A U.S. Commissions said in 2012 that China’s policymakers “view space power as one aspect of a broad international competition in comprehensive national strength and science and technology.” A report in 2015 from the University of California stated that ,”China’s efforts to use its space program to transform itself into a military, economic, and technological power may come at the expense of U.S. leadership and has serious implications for U.S. interests.”
        Critics of the law and these reports say that China has its own advanced space technology and would learn little from visiting the ISS. They point out that even though the Soviet Union was considered a severe threat during the Cold War, we still cooperated on space missions. They say that the best way to reduce any Chinese threat to utilize the exploitation of space to our disadvantage is to invite them to participate in the ISS, not to isolate and vilify them. Chinese astronauts have repeatedly said that they would like to participate in international space projects such as the ISS.
        The International Association of Space Activities Participants is an “association of enterprises engaged in space activities to enhance their economic cooperation, provide joint efforts in the implementation of joint projects, promote of products and services to the world markets, protect the rights of members of the Association, to represent them in government and other authorities, in international organizations.” It is mainly a Russian led organization. The Russians support inviting the Chinese to visit the ISS. A Russian source said that in 2014, a request was received by the IASP from the Chinese for authorization to visit the ISS. The Russians agreed to the Chinese request and are currently waiting for the U.S. to agree. The U.S. told the Russians that it needed time to consider the proposal.
        Considering that China has the third biggest national space program and has stated its interest in being involved in the ISS, it is ridiculous for the U.S. to continue to block their participation. The Chinese should be invited into the ISS project as soon as possible.
ISS Logo:

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             I was really excited when it was announced that the Space Trade Association was being started in Seattle where I live. I have been an avid reader of science fiction since I was a kid and have been eager to see the entry of private companies into peaceful exploration and exploitation of space. The STA wants to “bring a singular focus based on specific models describing technological, economic revolutions – how they impact the industrial system, change the economy, alter our social structures and create a new world” with respect to the commercialization of space.
        The STA says that there are over eight thousand aerospace workers in the Puget Sound area working on space related projects. Boeing is working with NASA on boosters and spacecraft. Amazon’s founder, Jeff Bezos, started Blue Origin. Microsoft founder, Paul Allen, started Vulcan Aerospace. Elon Musk, founder of PayPal and Tesla Motors, has chosen Seattle for the administrative offices of SpaceX. A company called Planetary Resources located in Redmond, Washington is working on asteroid mining projects. Spaceflight Inc. “provides launch services through various mission concepts that provide shared launch capability to multiple spacecraft.” Space Angels Network is “a global network for angel investors, offering insider access to the emerging private space industry and sophisticated investment opportunities across diverse market segments, with the expertise and network connections to cultivate stellar returns on investment. We are the largest community of space investors and entrepreneurs in the world.” Seattle is rapidly becoming a major hub for the infant space commercialization industry. There are rumors that there will be a major space conference in the Seattle area next year.
         Space Entrepreneurs mission statement reads: “Accelerate the progress humanity is making in creating a space tourism industry, a low-Earth orbit economy, and deep-space economic development and exploration. We will do this by empowering entrepreneurs and intrapreneurs with space-related ideas.” They were founded in February 2014 as a “physical and virtual network of individuals with ideas on what humanity’s future in and using space should be.” It was established for “Those who have an space-related idea and are wondering if they can make it a reality using entrepreneurship or intrapreneurship.” Their focus is on Seattle because it “is coalescing and growing as a hub for commercial space activity. Entrepreneurship is hard and so is space. It helps to have a group and community who can support you.”
       Every industry needs to have gatherings for networking and Space Entrepreneurs has decided that it is time for the Seattle space industry to have its own. On Thursday, August 27 from 5:30 to 9:00 PM, the Seattle: The Epicenter of Space event will be held at Marina Park in Kirkland, Washington, 25 Lakeshore Plaza drive. Chris Lewiki of CEO of Planetary Resources will speak about his company’s current work and future plans. Joe Landon, Managing Partner of Space Angels Network will talk about the space startup scene in the Seattle area. There will be food and drinks and lots of opportunity to meet the players in Seattle’s grown space industry. Attendance is limited to 100 so sign up early. Event Details.

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        I was thrilled when the U.S. landed a man on the Moon in 1969 and have been very disappointed that it is decades later and we have not sent any humans to the Moon in quite awhile. I could never understand how we could have done it the first time from scratch and with primitive equipment only to be told that it would take decades and break the bank to send humans up there again. Lately there has been a lot of talk about sending people to Mars, a much tougher mission. And a debate has been going on about whether we should go back to the Moon first before we go on to Mars. A new report funded by NASA shows that it won’t be anywhere near as expensive as has been estimated to return astronauts to the Moon. The report also supports the idea that we should go back to the Moon first.
        The NexGen Space study was produced by the National Space Society and the Space Frontiers Foundation with NASA funding. The report states that if NASA partners with private companies, we can return humans to the Moon for about ten billion dollars instead of the one hundred billion dollars that had been the previous estimate for a manned mission to the Moon. In addition to reducing the cost of travel to the Moon, the report says that utilizing the hydrogen and water on the Moon, the cost of travel beyond the Moon to destinations such as Mars could also be drastically reduced.
         The reason for the study was to assess whether or not public-private partnerships and other arrangements could yield a “low-cost and low-risk” method to getting people to the Moon and lay the groundwork for future missions beyond the Moon via what was called Evolvable Lunar Architecture.
         The study cites NASA’s investments in successful private spaceflight with its Commercial Orbital Transportation Services and its Commercial Resupply Services programs. By 2017, NASA expects to have two manned spacecraft, the SpaceX Dragon capsule and the Boeing CST-100 ready to test launch under its Commercial Crew Program. SpaceX is also working on the Falcon Heavy heavy launch vehicle and the United Space Alliance is working on the Vulcan heavy launch vehicle. These private launch vehicles can be used to launch manned capsules into space much cheaper than NASA’s Space Launch System. Reusable spacecraft, reusable launch vehicles and reusable lunar landers are under development as well.
         According to the report, the U.S. could send astronauts to the Moon in five to seven years for a total of ten billion dollars. It also says that in ten to twelve years an industrial base staffed with four astronauts could be operation at a total development cost of under forty billion dollars. Currently NASA’s budget allocates about four billion dollars a year for deep space exploration. Both of these programs could be run concurrently within the existing budget.
        The report went on to say that a manned base on the Moon would be capable of using hydrogen and water found there to produce up to two hundred million tons of fuel for spacecraft per year. This assumes that robotic missions to the Moon can verify that hydrogen and water are accessible inside craters at the lunar north pole. This fuel could be used for missions to Mars and would substantially reduce the cost of such missions. “A permanent commercial lunar base might substantially pay for its operations by exporting propellant to lunar orbit for sale to NASA and others to send humans to Mars, thus enabling the economic development of the Moon at a small marginal cost.” The report called for the creation of an International Lunar Authority to manage the public-private program for the lunar base and fuel business.
       NASA is currently sending missions to asteroids as a prelude to a Mars mission but a previous report by the National Research Council suggested that a return to the Moon might be a better and cheaper option for preparing for a Mars mission.
Concept art from NASA for a manned lunar installation:

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      One of the interesting trends in science fiction in the past thirty years has been the emergence of “steampunk”. “Steampunk refers to a subgenre of science fiction and sometimes fantasy that incorporates technology and aesthetic designs inspired by 19th-century industrial steam-powered machinery.” I have read some of these books and gone to a couple of steampunk conventions. When I thought about why steampunk was popular, it occured to me that part of the reason was the aesthetic designs mentioned in the quote from Wikipedia.
       A great deal of modern technology is designed to function well but no thought is really given to aesthetics. Compare the old fancy train engines to the new modern trains. The same could be said for a lot of scientific equipment. Old equipment was often engraved and mounted on polished wood. New equipment is packaged in bland functional cases. I think a lot of the attraction of steampunk is related to the visually elaborate and artistic designs either described or shown in the stories.
     Our exploration of space is carried out by highly functional but relatively ugly probes and landing vehicles. This may be about to change.
     Google is sponsoring the Lunar XPRIZE competition. The winner of the competition will be the first privately funded effort to land a rover on the moon, travel five hundred meters and send back high definition photographs and video. The first prize is twenty million dollars. The second team that succeeds at the task will receive ten million dollars. Other prizes will be awarded for surviving the lunar night or visiting an Apollo landing site.
      Audi, the automobile manufacturer, has teamed with a German engineering group called the Part-Time Scientists to enter the Lunar XPRIZE competition with the Lunar Quattro. The PTS core group has varied between ten and thirty five people. They have been working on the project since 2009 and have constructed two prototypes. Partnering with Audi gave the PTS access to Audi’s Munich-based advanced design studio. An Audi designer said that their lunar rover had to be effective in the harsh lunar conditions but that it also had to express the “familiar aesthetics that are expected of Audi.”
      The PTS have tested and refined many of the technical features of the Lunar Quattro such as the solar panel array that provides power and the supplemental battery to provide power after the sun has gone down. Each of the wheels of the Quattro is independently driven by its own electric motor. Each wheel can rotate three hundred and sixty degrees for maximum maneuverability. Two cameras in the movable head will help with navigation by acquiring three dimensional terrain maps. A third camera will send high-definition still shots and video sequences back to Earth.
        After more tests and refinements in extreme climate test chambers, the Lunar Quattro is scheduled to launch before the end of 2017. The intended landing site for the Quattro is near the place where Apollo landed in 1972.
        Returning to the comments at the top of this column, the image below will show that the Audi designers did not disappoint with respect to presenting the “familiar aesthetics that are expected of Audi.” The Lunar Quattro is sleek and beautiful compared to all the other lunar rovers that have landed on the moon. Perhaps more aesthetic designs will be found for other space hardware in the future.

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Part Two of Two Parts:
      In 2013, The German Aerospace Center announced a study to research how the DC technology might be of use to the European space missions. The project was called Dream Chaser for European Utilization. The missions being considered included resupply of the International Space Station and missions to higher orbits.
      In early 2014, the European Space Agency became a partner on the DC4EU project. Part of the ESA research involved finding out if the DC could make use of ESA avionics and docking technology. Another problem that the ESA investigated had to do with the launch vehicle. They were considering using the European Ariane 5 heavy launch vehicle which has a cargo covering fairing. To fit within the fairing, the DC would have to be reduced slightly in size.
      In January of 2014, there was an announcement that the Dream Chaser orbital test vehicle was under contract to be launched on an orbital test flight atop an Atlas V booster from Kennedy Space Center in late 2016. Then, in September of 2014, NASA failed to select the Dream Chaser for the next phase of the Commercial Crewed program due to its “lack of maturity.” SCN filed suit against NASA and work by Boeing and SpaceX on crewed space craft under the NASA program was temporarily halted but then restarted by another court ruling. Ultimately, SCN lost its challenge against the NASA contracts for Boeing and SpaceX.
        Shortly after losing the NASA contract, SCN announced that it was working with the Stratolaunch Systems air launch system. About the same time, SCN announced the Dream Chaser Global Project to ” provide customized access to low Earth orbit to global customers.” At the end of 2014, Vulcan Areospace released their design for combining a scaled down Dream Chaser with the Stratolaunch launch system. The system would include the 75% scale Dream Chaser which is twenty two feet long with a eighteen feet wingspan. It will be able to carry two or three crew and have room for scientific instruments.
        The European Space Agency has also been seriously considering the full sized Dream Chaser design for European space missions such as low-Earth orbit missions, microgravity research, satellite servicing and active debris removal. OHB System AG, a German space company, has stated that, “The inherent design advantages of the Dream Chaser reusable lifting body spacecraft make it an ideal vehicle for a broad range of space applications,” said Dr. Fritz Merkle, member of the Executive Management Board of OHB AG. “We partnered with SNC to study how the design of the Dream Chaser can be used to advance European interests in space. The study results confirm the viability of using the spacecraft for microgravity science and ADR. DC4EU can benefit the entire international space community with its unique capabilities. We look forward to further maturing our design with SNC as we expand our partnership.” A cooperation agreement between SCN and OHB was renewed in April 2015 for additional two years.
       The cargo version of the DC has an expendable cargo section. SCN has proposed the cargo version for possible use in resupply of the ISS. In order to satisfy diverse launch requirements, the cargo version will have foldable wings which will let it be enclosed in a fairing. This version could be launched with either the European Ariane 5 or the U.S. Atlas V. Both the passenger version and the cargo version of the DC are serious contenders in the race to develop commercial space planes.
Dream Chaser:

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Part One of Two Parts:
        Today I am going to blog about the Dream Chaser, a winged mini-shuttle under development by the Sierra Nevada Corporation. The DC is a reusable crewed suborbital and orbital lifting body spaceplane. The DC was originally designed to be launched on top of a heavy launch vehicle. After missions, the DC will land horizontal on conventional runways. The Dream Chaser design considered by NASA was thirty feet long with a twenty three foot wingspan. It would be about to carry up to a crew of seven for a two hundred and ten day missions.
        The “lifting body” concept has a long history. The X-20 Dyna-Soar concept was developed in the U.S. in 1957. In 1966, Northup researched the M2-F2 and Martin X-23 Prime lifting body designs. The DC is based the 1990 NASA HL-20 lifting body design which evolved from the NASA HL-10 design from the around 1970. The DC design including ideas taken from the Soviet Mikoyan-Gurevich MiG-105 military space plane design which was a response to the X-20 Dyna-Soar research.
       The DC uses reaction control thrusters which burn ethanol-based fuel which has the  benefit of not being an explosive volatile substance. This means that the DC can be handled by ground crews immediately after landing as opposed to the Space Shuttle which needed to have the fuel removed before work by ground crews. The thermal shielding is replaced as a whole instead of tile by tile as with the Space Shuttle heat shield. The orbital propulsion system consists of twin hybrid rocket engines. The engines burn hydroxyl-terminated polybutadiene  and nitrous oxide. Both of these substances are non-toxic and easy to store which makes them safer than liquid fuels used in most rockets. The hybrid engines can be stopped and started and their thrust can be controlled.
        The Dream Chaser name has been used twice by Jim Benson at SpaceDev, the originator of both designs. One design was a for an orbital craft based on the HL-20. SpaceDev tried to get NASA to consider this Dream Chaser for a mini-shuttle and for the NASA Commercial Orbital Transportation Services program. When the Dream Chaser was not selected for NASA programs, Jim Benson started Benson Space Company to create another Dream Chaser for suborbital tourist flights. In 2007, SpaceDev partnered with the United Launch Alliance to work on the idea of launching their Dream Chaser orbital craft on an Atlas V booster. Later in 2007, SpaceDev signed an agreement with NASA.
        Following the death of Jim Benson in 2008, SpaceDev was acquired by the Sierra Nevada Corporation. In 2010, SNC was awarded a twenty million dollar contract by NASA under the Commercial Crew Development phase 1 program to develop their Dream Chaser. SNC completed the four required milestones on schedule including program implementation plans, manufacturing readiness capability, hybrid rocket test fires, and the preliminary structure design. In 2011, NASA gave SCN eighty million dollars for CCDev 2 work on the Dream Chaser. More milestones were met and in 2012, SCN got two hundred and twelve million dollars from NASA for Dream Chaser development under the Commercial Crew Integrated Capability program. 
Dream Chaser:

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       I have made it clear in many posts that I do not think that nuclear power is appropriate for massive generation of commercial electricity. There are many reasons for my opinion that I have detailed over the past two years. That is not to say that there are not appropriate uses for nuclear materials. A large number of medical diagnostic and therapy procedures depend on radioactive isotopes. There are many industrial applications as well. However, even these uses have problems from production to disposal that can be problematic. One use for radioactive materials that does not have disposal problems are energy sources for space probes although there is a danger of pollution if a launch vehicle with radioactive materials on board explodes on launch or crashes back to Earth. While current use of nuclear materials on spacecraft is in the form of nuclear batteries that supply electricity for equipment and ionic engines, there is a history of projects aimed at the explosion of nuclear bombs in space for propulsion and research.
        The early history of nuclear devices and space began at the dawn of the Atomic Age in the 1950s. In 1957, there was a series of nuclear tests called Operation Plumbbob at the U.S. Nevada nuclear test site. There were twenty nine explosions that were used for a series of experiments on the effects of nuclear explosions on materials, humans, structures and equipment. During an underground test known as Pascal-B, in August of 1957, a four inch thick steel cap weighing hundreds of pounds was blown off and may have been launched into solar orbit. Although unintended, nonetheless, this may have been a successful launch of a payload from the surface of the Earth via nuclear explosion.
       Project A119 was a plan developed in 1958 to send a nuclear bomb to the Moon and detonated it on the surface. Apart from the scientific knowledge that might have been gained, there was also the idea that a nuclear detonation on the Moon that would be visible from the Earth would be a warning to the enemies of the United States. The project as never carried out and its existence was only revealed in 2000.
        The idea of using nuclear bombs for propulsion of interplanetary spacecraft was first proposed by Stanislaw Ulam, a mathematician working on nuclear weapons development in Los Alamos, New Mexico in 1947. A formal project development was undertaken in 1958 under the name of Project Orion. First proposals for launching a spacecraft with nuclear bombs were scrapped because of the fallout that would result. Later proposals were to launch with conventional rockets or to assemble in space. Nuclear propulsion would only be used in space. The project was cancelled following the Partial Test Ban Treaty of 1963. However, the development of designs for using nuclear explosions to propel spacecraft have continued to be developed with more recent systems using explosive pellets instead of large nuclear bombs. Both fission and fusion systems have been considered.
Project Orion Concept Art:

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