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China accelerates space program plans

By Richard Trombly

24 Feb 2011, Beijing – China announced that its Shenzhou 9 launch will be a manned mission to the Tiangong-1 (Heavenly Palace -1) space module after the successful robotic docking of the unmanned Shenzhou 8 with the orbiting space lab module in November of last year.  The launch is planned for June or July.

The next manned mission was planned to be later this year with Shenzhou 10 but spokesperson for the manned space program Wu Ping announced that  Shenzhou 9 will carry three astronauts and it will not only be another opportunity to test manual docking technology but also for a brief mission of scientific experiments within the 8.5 tonne station, said the spokesperson. The Tiangong -1 module was successfully launched in September.

An astronaut on an EVA during Shenzhou – 7 (Xinhua)

The Shenzhou module and its Long March II rocket have been completed and are undergoing testing and safety checks according to the spokesperson. China also hinted that this year’s Shenzhou 10 launch would include female astronauts who are currently in training, and that Tiangong – 1 would become part of a full spacestation to be completed by 2020 along with launches of Tiangong – 2 and Tiangong – 3, said the spokesperson. Original plans for Tiangong – 1 had involved letting it descend and burn up after Shenzhou 10.

The Shenzhou – 9 mission will be the fourth manned space mission since Yang LiWei orbited Earth in Shenzhou 5 and became China’s first astronaut in 2003 and making China the third country to successfully launch a human into space.

This represents an accelerated schedule of both manned launches and in the development of the China space station. Though projected to be much smaller than the current US-constructed collaboration, the International Space Station, the combined Tiangong station will reach 60 tonnes. But it is only a part of China’s developing space industry including a web of satellites and its own GPS system as well as more Moon probes after the success of Chang’e 2 which completed its Moon survey and is off to explore the Lagrange points in deep space.

China announced further plans late last year for human exploration on both the Moon and later to Mars. It already has plans for the Chang’e 3 and 4 probes. The Moon landing was outlined in China’s space roadmap released late last year which says China will “push forward human spaceflight projects and make new technological breakthroughs, creating a foundation for future human spaceflight”, and describes preparations for orbiting laboratories, space stations and studies that underpin “the preliminary plan for a human lunar landing.” It was hinted that the Moon landing, the first since Apollo 17 in 1972, was slated for 2025 but recently China has advanced the timetable and investment in its other space endeavors with a Lunar mission possible before 2020.

According to Shanghai Security News, although it did not reveal its sources, China will spend more than USD$50 billion in the next decade on up to 20 space ship launches. It is a part of the space roadmap that involves investing heavily in developing China’s space industry and launch capabilities.

This comes as India is renewing its own commitment to space. As a neighbor to China, scientists in India are well aware of China’s heating up of the space race. In the 90s India was seen as a leader in launching satellites and had announced plans in the early part of this century to send unmanned missions to Mars but India has seen China develop heavy launch vehicles that can launch nearly 10 tonnes while India is limited by the 2.5 tonne payload of its own current rockets. But former ISRO chairman, U. R. Rao addressed a gathering of scientists last week at Sri Venkateshwara University and discussed the commitment of India to develop its sciences programs, increase interest among students and renew its commitment to go to Mars.

This came just before the announcement that a teen from India, Sachin Kukke, has been selected as a winner of the YouTube Space Lab science competition, said the U.S.-based company. The  18-year-old Bangalore engineering student won for his experiment on how microgravity affects the thermal conductivity of a ferrofluid subject to a magnetic field and how heat transfers in these magnetic liquids called ferrofluids which might be used to create advanced cooling systems.

All of this as NASAs own 10-year survey outlines austere spending on planetary sciences from 2013 – 2022 and slashes funding for two proposed Mars missions in 2016 and 2018. So NASA Mars exploration past the Mars Science Lab currently underway to the red planet will be virtually unfunded under the current plan.

While the U.S. has made vast advances in robotic space research but has not made serious advances in human missions since the development of the shuttle. With the retiring of the fleet the U.S. is currently reliant upon Russia to even reach the U.S.-constructed ISS. Perhaps China’s efforts will spur the USA to get back into the space race that China is currently gearing up to win.

Richard Trombly is  Public Outreach director for The Mars Initiative http://www.themarsinitiative.org/

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China Moves Toward Permanent Space Presence

August 31,2011

Ivan Broadhead | Hong Kong

Read the original story at  http://www.voanews.com/english/news/asia/China-Moves-Toward-Permanent-Space-Presence-128773673.html

Visitors sit besides a model of Chinese made Tiangong 1 space station at the 8th China International Aviation and Aerospace Exhibition, known as Airshow China 2010, in Zhuhai city, south China, Guangd

Photo: AP
Visitors sit besides a model of Chinese made Tiangong 1 space station at the 8th China International Aviation and Aerospace Exhibition, known as Airshow China 2010, in Zhuhai city, south China, Guangdong province (2010 File)

China is expected to launch its Tiangong 1 space laboratory in the coming days. A country that only eight years ago put its first taikonaut (astronaut) into orbit could, in eight more years, be the only country to possess a permanently-crewed space station.

Chinese media report that the Tiangong 1, or “Heavenly Palace”, is being readied for flight at the Jiuquan launch facility in Inner Mongolia.

The module represents the first element of China’s plan to develop a manned space station, which Beijing hopes will be fully operational by 2020.

Professor Kwing-Lam Chan of Hong Kong University of Science and Technology is involved in analysis of China’s lunar program. He explains the objective of this first Tiangong mission:

“It’s a lab for testing the connection between spacecraft: Shenzhou 8 will be sent [up] probably this year, and will be connected to Tiangong 1 for testing, but will not carry people,” he said.

State media report that China’s space program aims to enhance the country’s “progress, power and prestige”.

Under military authority, it has advanced rapidly despite European Union and U.S. embargoes on trading in defense-related technologies with China.

The Shenzhou spacecraft emerged from Russian Soyuz technology in the late 1990s. A first manned space mission for China followed in 2003, making a national hero of the taikonaut Colonel Yang Liwei.

Professor K.L. Yung of Hong Kong Polytechnic University is helping develop equipment that China will use on the Moon next year.

He suggests that while China’s space program is no more advanced those of other space-faring nations, a team of elite engineers and scientists is making incremental and cost-effective progress.

“The main reason is obviously salaries in China are not that high. The other reason is, they are developing a lot of their own components because of the high-tech embargo; it actually helps them.”

With the International Space Station, funded by Russia, the United States, Canada, Japan and the EU, slated for retirement in 2020, Yung points out that China could soon emerge as the only nation with a permanent, manned space platform.

The potential for such a strategic advantage in space, aligned with China’s ballooning defense budget, is causing international concern.

Last week, the U.S. Defense Department published its annual report on China’s military capabilities.  The report concluded that Beijing is developing “extensive space warfare technologies”.

The report also found little evidence that “China’s leaders have fully thought through the global effects of employment of these strategic capabilities”.

Although Beijing insists it “opposes the weaponization of space”, India, Japan and Korea continue to play catch up with their own indigenous space programs.

However, Chan is convinced China is receptive to cooperation, on its terms:

“I am very impressed by the quality of the people on the space enterprise in China and I believe they want to collaborate, on equal grounds.”

Tiangong 1 is at least the fourth space launch China has conducted since mid-August. However, the ambitious pace of the launch schedule is now under scrutiny after August 18th, when an experimental orbiter launched from Jiuquan failed to enter orbit when the rocket carrying it malfunctioned.

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Wall Street Journal Publishes Zubrin Plan to Use SpaceX Hardware to Send Humans to Mars This Decade


May 16, 2011


In its May 14th issue, the Wall Street Journal, one of America’s top newspapers, published a commentary article by Dr. Robert Zubrin, President of the Mars Society, laying out a radical new plan for accomplishing a humans-to-Mars mission in this decade by using hardware systems soon to be fielded by SpaceX, a leading American space transport company.  The full article by Dr. Zubrin is presented below.

A paper containing additional material explaining the basis of the proposed mission plan can be found at: http://www.marssociety.org/home/press/news.  In addition, Dr. Zubrin will give a special in-depth presentation on the mission plan at the Fourteen Annual International Mars Society Convention, to be held in Dallas, Texas, August 4-7, 2011.

How We Can Fly to Mars in This Decade – And on the Cheap

The technology now exists and at half the cost of a Space Shuttle flight. All that is lacking is the political will to take more risks.


By Robert Zubrin, Wall Street Journal, May 14, 2011

SpaceX, a private firm that develops rockets and spacecraft, recently announced it will field a heavy lift rocket within two years that can deliver more than twice the payload of any booster now flying. This poses a thrilling question: Can we reach Mars in this decade?

It may seem incredible—since conventional presentations of human Mars exploration missions are filled with depictions of gigantic, futuristic, nuclear-powered interplanetary spaceships whose operations are supported by a virtual parallel universe of orbital infrastructure. There’s nothing like that on the horizon. But I believe we could reach Mars with the tools we have today, or will have in short order. Here’s how it could be done:

The SpaceX’s Falcon-9 Heavy rocket will have a launch capacity of 53 metric tons to low Earth orbit. This means that if a conventional hydrogen-oxygen chemical rocket upper stage were added, it would have the capability of sending 17.5 tons on a trajectory to Mars, placing 14 tons in Mars orbit, or landing 11 tons on the Martian surface.

The company has also developed and is in the process of demonstrating a crew capsule, known as the Dragon, which has a mass of about eight tons. While its current intended mission is to ferry up to seven astronauts to the International Space Station, the Dragon’s heat shield system is capable of withstanding re-entry from interplanetary trajectories, not just from Earth orbit. It’s rather small for an interplanetary spaceship, but it is designed for multiyear life, and it should be spacious enough for a crew of two astronauts who have the right stuff.

Thus a Mars mission could be accomplished utilizing three Falcon-9 Heavy launches. One would deliver to Mars orbit an unmanned Dragon capsule with a kerosene/oxygen chemical rocket stage of sufficient power to drive it back to Earth. This is the Earth Return Vehicle.

A second launch will deliver to the Martian surface an 11-ton payload consisting of a two-ton Mars Ascent Vehicle employing a single methane/oxygen rocket propulsion stage, a small automated chemical reactor system, three tons of surface exploration gear, and a 10-kilowatt power supply, which could be either nuclear or solar.

The Mars Ascent Vehicle would carry 2.6 tons of methane in its propellant tanks, but not the nine tons of liquid oxygen required to burn it. Instead, the oxygen could be made over a 500-day period by using the chemical reactor to break down the carbon dioxide that composes 95% of the Martian atmosphere.

Using technology to generate oxygen rather than transporting it saves a great deal of mass. It also provides copious power and unlimited oxygen to the crew once they arrive.

Once these elements are in place, the third launch would occur, which would send a Dragon capsule with a crew of two astronauts on a direct trajectory to Mars. The capsule would carry 2500 kilograms of consumables—sufficient, if water and oxygen recycling systems are employed, to support the two-person crew for up to three years. Given the available payload capacity, a light ground vehicle and several hundred kilograms of science instruments could be taken along as well.

The crew would reach Mars in six months and land their Dragon capsule near the Mars Ascent Vehicle. They would spend the next year and a half exploring.

Using their ground vehicle for mobility and the Dragon as their home and laboratory, they could search the Martian surface for fossil evidence of past life that may have existed in the past when the Red Planet featured standing bodies of liquid water. They also could set up drilling rigs to bring up samples of subsurface water, within which native microbial life may yet persist to this day. If they find either, it will prove that life is not unique to the Earth, answering a question that thinking men and women have wondered upon for millennia.

At the end of their 18-month surface stay, the crew would transfer to the Mars Ascent Vehicle, take off, and rendezvous with the Earth Return Vehicle in orbit. This craft would then take them on a six-month flight back to Earth, whereupon it would enter the atmosphere and splash down to an ocean landing.

There is nothing in this plan that is beyond our current level of technology. Nor would the costs be excessive. Falcon-9 Heavy launches are priced at about $100 million each, and Dragons are even cheaper. Adopting such an approach, we could send expeditions to Mars at half the mission cost currently required to launch a Space Shuttle flight.

What is required, however, is a different attitude towards risk than currently pervades the space policy bureaucracy. There is no question that the plan proposed here involves considerable risk. So does any plan that actually involves sending humans to Mars, rather than talking about it indefinitely. True, there are a variety of precursor missions, technology developments, and testing programs that might be recommended as ways of reducing risk. There are an infinite number of such potential missions and programs. If we try to do even a significant fraction of them before committing to the mission we will never get to Mars.

But is it responsible to forgo any expenditure that might reduce somewhat the risk to the crew? I believe so. The purpose of the space program is to explore space, and its expenditures come at the cost of other national priorities. If we want to reduce risk to human life, there are vastly more effective ways of doing so than by spending $10 billion per year for the next two or three decades on a human spaceflight program mired for study purposes in low Earth orbit. We could spend the money on childhood vaccinations, fire escape inspections, highway repairs, better body armor for the troops—take your pick. For NASA managers to demand that the mission be delayed for decades while several hundred billion dollars is spent to marginally reduce the risk to a handful of volunteers, when the same funds spent elsewhere could save the lives of tens of thousands, is narcissistic in the extreme.

The Falcon 9 Heavy is scheduled for its first flight in 2013. All of the other hardware elements described in this plan could be made ready for flight within the next few years as well. NASA’s astronauts have gone nowhere new since 1972, but these four decades of wasteful stagnation need not continue endlessly. If President Obama were to act decisively, and bravely embrace this plan, we could have our first team of human explorers on the Red Planet by 2016.

The American people want and deserve a space program that is really going somewhere. It’s time they got one. Fortune Favors the Bold. Mr. President, seize the day.

Dr. Zubrin is president of Pioneer Astronautics and of the Mars Society (www.marssociety.org). An updated edition of his book, “The Case for Mars: The Plan to Settle the Red Planet and Why We Must,” will be published by The Free Press this June.


For further information about the Mars Society, visit its website atwww.marssociety.org

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The Space Review: The case for international cooperation in space exploration.

IXO illustration

The International X-Ray Observatory is one of three large space science missions ESA is considering funding, with some degree of cooperation with other space agencies, such as NASA. (credit: NASA)

The case for international cooperation in space exploration

by Lou Friedman
Monday, February 21, 2011

Comments (2)
Bookmark and ShareI owned an American car built in Australia from an Italian design with Japanese parts. It is trite now to comment on globalization and interdependency of world industry. The International Space Station is an extraordinary testament to how globalization and international cooperation have permeated the space program. The United States and Europe have also merged their planning for future robotic space exploration ventures to Mars and the outer planets. If these plans materialize, they will enable much more to be accomplished than could be done in national programs.

International cooperation is enabling a golden era of robotic space exploration even in the face of budget cuts and increasing costs.

The interdependency of national space programs will play a part in the big space exploration decision that Europe has to make later this year: what to explore in the 2020s. Because of the complications of having over a dozen nations involved in decision-making and project implementation, the European Space Agency has to make decisions long in advance of their technical necessity. They will probably decide this year or next on their next big step in space exploration and choose a mission that will probably not launch until well into the 2020s.

They are considering their first outer planets mission: an orbiter of Jupiter and its giant moon Ganymede, to fly as a companion to NASA’s putative Europa orbiter. An International X-Ray Observatory is also being considered in cooperation with both NASA and JAXA, the Japan Aerospace Exploration Agency. It would be a large telescope companion to the James Webb Space Telescope at the Sun-Earth Lagrangian point, L2. The third candidate in the science competition is a gravity wave detector called LISA, Laser Interferometer Space Antenna. It would be a cooperative mission with NASA, utilizing three satellites.

The decision on which of these three large-class science missions to develop could come in the middle of this year. NASA and JAXA decisions will clearly affect European decision-making, and vice versa. I am concerned that the lack of funding in the president’s proposed budget for an outer planet flagship mission, expected to be a Europa orbiter, might lead ESA to give up on its Ganymede companion. But perhaps it will have the opposite effect, since it could be re-cast as an independent mission and allow Europe to take over from the US as the main outer planets explorer in the 2020s. LISA and IXO are more interdependent international missions, and LISA in particular will be affected by the proposed cuts in US space science. IXO could be done solely with Japan, but Japan is having its own space science budget problems and might be influenced by the cuts in other countries. The European Union is having its own furious debate about debt and budgets, and ESA budget cuts to their existing program are possible despite the fact that their planning tends to be more stable because of the long lead times.

For several years ESA has been developing a highly ambitious ExoMars astrobiology mission for Mars exploration. It was so ambitious that they had to step back and make it part of a cooperative plan with NASA, beginning with a 2016 entry, descent, and landing technology test vehicle that would fly as companion to the US Mars Trace Gas Orbiter. That latter mission was included in the President’s budget, but the follow-on cooperative NASA lander to fly in conjunction with ExoMars was not. How will that affect ESA planning?

In their budget rollout last week, NASA officials described how they have given up on a US dark energy astrophysics mission, and instead will focus on cooperating with the Europeans’ nascent Euclid mission. Euclid is one of three so-called medium class science missions competing for final selection this year to launch near the end of the current decade. The others are an exoplanet detection mission called PLATO and a solar orbiter to study the Sun. Two will be selected (we hope).

The world needs a positive, inspiring, outward-looking venture that can engage skilled personnel around the world in developing new technology. Let’s back off from the national-only planning and start planning internationally.

In short, international cooperation is enabling a golden era of robotic space exploration even in the face of budget cuts and increasing costs. It’s a touchy situation because interdependency not only builds up new capabilities but can, because of the dependency, undermine the planning. And the current focus on budget cutting in all countries could undermine everything, stopping space exploration just as Spain, Portugal, and Holland stopped ocean exploration centuries ago.

However, given the fact that globalization already dominates exploration of the solar system and observation of the universe, and that the International Space Station has now merged the human space flight programs of spacefaring nations, why don’t we strengthen human exploration planning with an international approach? Strengthening is badly needed. How much of a leap is it to combine robotic Mars landers with International Space Station missions to produce a program that takes humans into the solar system?

In my view it is time for the political leaders (not just the space agency heads) to get together on a new human space initiative. It is clear that the US and Russia are not going to do it alone despite the assertions by space enthusiasts in both countries that they can. Europe and Japan have shown themselves to be strong players with meaningful contributions. China and India are standing on the threshold.

As I have said many times, space agency folks alone can’t make it happen: only a geopolitical purpose will drive support for a major human space mission. The world needs a positive, inspiring, outward-looking venture that can engage skilled personnel around the world in developing new technology. Let’s back off from the national-only planning and start planning internationally. Budget realities, if nothing else, demand it. Maybe Europe, which has overcome many of the nationalistic inhibitions to cooperation, should step up and be a leader in making it happen.


Lou Friedman recently stepped down after 30 years as Executive Director of The Planetary Society. He continues as Director of the Society’s LightSail Program and remains involved in space programs and policy. Before co-founding the Society with Carl Sagan and Bruce Murray, Lou was a Navigation and Mission Analysis Engineer and Manager of Advanced Projects at JPL.

 

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http://journalofcosmology.com/Mars153.html

Journal of Cosmology, 2010, Vol 12, xxxxx.
JournalofCosmology.com, January, 2011


The Mars Homestead For An Early Mars Scientific Settlement Bruce Mackenzie, Ph.D.1, Georgi Petrov, Bart Leahy, and Anthony Blair
1Mars Foundation, 102 Sanborn Ln, Reading, MA 01867-1009, USA


Abstract

The Mars Homestead is a major project of The Mars Foundation. The goal is to develop a detailed plan for a permanent Mars Scientific Settlement similar to the NASA Design Reference Mission. Emphasis is placed on achieving success as early as possible, and maximizing the use of local resources. Two variations of the master plan are considered. The first is a hillside linear layout. The second, still under development, is a redesign that places the same program in an open plain site. The first crew on Mars would delay major scientific studies to concentrate on producing building materials, habitat construction and food. After the initial base is complete, construction would continue, allowing an additional dozen scientists to arrive every two years, bringing only their personal effects and specialized equipment. The cost of sending the manufacturing equipment can be recouped by eliminating the cost to return later crews to Earth after short rotations. Preliminary estimates show that the launch cost of a permanent scientific base for a dozen scientists (and growing) would be the same as the “Design Reference Mission” for three round-trip missions of six people each, while avoiding the significant risks of multiple return trips to Earth. Given the cyclical history of aerospace funding, this plan to establish an early permanent scientific base and grow it into a vigorous settlement may advance the settlement of space by an entire generation. Participation is welcome to everyone, including contributions by non-aerospace engineers.
Key Words: Mars, Space Settlement, Space Colonization, in-situ resource, construction, life in extreme environments, Astrobiology, space radiation environment



1. Introduction

The Mars Homestead Project is the key endeavor of the Mars Foundation™, a non-profit, 501(c)(3) organization dedicated to establishing permanent, thriving settlements beyond Earth, starting with Mars. The goal of the project is to develop a reference design for the first permanent Mars settlement built primarily from local resources. This early, permanent base can support scientific investigations more cost effectively and safely than a series of round-trip missions. Likewise, instead of focusing on the application of a single technology, the project takes a broad view of all the necessary structures and materials for the constructing the initial 12-person phase of a growing settlement.

Preliminary estimates indicate that the delivered mass to establish a permanent scientific base for the initial dozen scientists would total about 250 tons. This is approximately the same mass as NASA’s Design Reference Mission (DRM), but is more cost effective. The DRM proposes three round-trip missions of six people each, totaling less than 24 person-years of time on the surface over a decade. Our alternative delays scientific studies, though it supports 12 person-years of effort each year, quickly growing to 24, 36, and more person-years every other year.

This cost savings is possible by eliminating the need for most return flights, their fuel manufacture, and consumables. Given the cyclical history of aerospace funding, it is critical to establish a reasonably self-sufficient base before enthusiasm and funding wanes. Prior to the crew’s arrival, pre-positioned habitats, food, and equipment will be sent to Mars to produce: power, breathing gases (oxygen (O2), nitrogen (N2), and argon (Ar), water, fuel, and possibly industrial materials. The initial crew of four would concentrate on establishing long-term life support equipment, and would set up automated equipment to produce building materials, such as fiberglass, polymers, ceramics, glass and brick. Assuming the life-support system is reliable, they would then be joined by two more crews, bringing the total to 12 people. After full production equipment is in service, they would assemble additional manufacturing modules, greenhouses, labs, and living quarters built from local materials. Construction would continue after the crew moves to the permanent living space, allowing additional crews to arrive every two years. The new arrivals need only bring their personal effects and specialized equipment, allowing the scientific base to grow at about one-third the cost of round-trip missions.

2. Hillside Settlement

A detailed master plan for a “Hillside Settlement” has already been established. It would include living quarters, workshops, greenhouses, maintenance facilities, waste processing, refining, manufacturing, and other areas needed to live and work (Figure 1). Once the team establishes residency in their completed quarters, they will resume construction of additional facilities to hold another dozen persons, mainly scientists who will arrive every subsequence two years. As progress continues, the base will grow into a permanent manufacturing settlement, producing equipment for additional scientific outposts and other permanent settlements.

Figure 1. Aerial View Of The Hillside Settlement, At The Stage When First Occupied By 12 People.2.1 Plains Settlement Realizing that a convenient hillside might not be available near the desired settlement location, the team is now undertaking a new study to adapt the same program to an open plain area, or most any site which is flat enough to be a good spacecraft landing site. One of the primary differences between the hillside and the plains settlements is the lack of radiation shielding provided by the hillside. Preliminary images are shown in Figure 2.

Materials The plains settlement could be located anywhere on Mars where there are available water (as ice in the soil) and silicates suitable for the manufacture of fiberglass. If water-ice is not available, it could extracted from the air, but at an unreasonable cost. If fiberglass is difficult to manufacture from the local soils, alternate materials are possible, including: polymers such as polyester and nylon, spun basalt, recycled aluminum, iron and steel from the iron carbonyl process. As many materials as possible would be produced locally using general purpose equipment sent from Earth.

Interior furnishings could be constructed of locally produced fiberglass, plastic, pressboard panels, extra piping, parachute cloth, and masonry. Once extra greenhouse space is available, bamboo, paper, soybean oil, cloth, and other plant products grown on site could provide additional raw materials for furnishings.

Cylindrical Habitats Materials such as fiberglass and polyester would be used for fabricating pressurized horizontal cylindrical habitats. They are arbitrarily dimensioned to be 5 meters in diameter and 20 or 30 meters long. This provides significant width of the floor, and space below the floor and above a ceiling for equipment and storage. Connection rings are 2.5 meters in diameter. Additional spherical connection nodes allow 4 cylindrical modules to be connected together. This avoids the structural problems of connecting to the side of a cylindrical module.

Large inflatable ‘assembly tents’ house bulky fabrication and fiberglass spinning equipment, and provide valuable factory floor space (left-foreground in Figure 2). Half-sized modules would be spun on a fiber glass lathe, and then joined together in a separate ‘finishing tent’, which also serves as an air-lock (middle-foreground in Figure 2).

Figure 2. Aerial View of the Plains Settlement, With Shielding Canopy Cut BackRadiation Shielding Canopy Sintered bricks would be used for foundations supports and load bearing columns. The columns support an overhead canopy holding regolith for radiation sheilding. Protection against cosmic rays can be improved at a later date by adding a top layer of any material with lightweight atomic nuclei, such as bags of water-ice, waste plant material, or any carbon-based compound; when such materials are available. Gaps below the modules and between the modules and canopy are critical for external maintenance and cooling. This design of raised modules can be adapted for a polar settlement built on permafrost, provided the foundations are kept cool by the wind. In Figure 2, the canopy is partially cut back to show the horizontal cylindrical habitats and spherical connection modules.

A possible alternative is to construct a box frame around the cylindrical module (not shown). This allows more assembly to be performed indoors. The modules may be stacked when the settlement is large enough to justify two story structures. Overhead trays constructed indoors as part of the box frame would later be covered with regolith for radiation shielding.

Other Features To allow extra light and overhead radiation shielding, greenhouses would be lit through side windows from external gimbaled mirrors (shown and described later in this paper). The settlement primarily utilizes nuclear power (not shown), not just for electrical generation, but also for industrial heat, such as manufacture of polymers, preheating during sintering of ceramics, manufacture of fuels, and breathable air.

Note the ‘observation deck’ rising above the canopy in the background of Figure 2. It has water tanks in the ceiling and awning for radiation shielding. The observation deck nominally serves as a supervisory station for construction of settlement and vehicles, much like an airport control tower, but with ubiquitous remote cameras that is not really needed. The real justification for it is psychological; it provides a place with a spacious view for meals, small meetings, private relaxation, and a sense of accomplishment, which are critical for settlers who will be on Mars for many years.

3. Martian Technologies / Social Considerations

Any task as massive and difficult as exploring and settling Mars requires advance planning, development, and other efforts to literally and figuratively “get off the ground.” These steps include feasibility studies, prototype projects, operational and environmental research, identifying funding sources, hardware development, and preliminary exploration. The Foundation has already taken the first step by developing a feasibility study and—like NASA, though with a different emphasis—a design reference mission. The Mars Homestead Project—our feasibility study—began by identifying the basic mission of a Mars settlement and the primary challenges involved in building such a habitat.

3.1 Marian Settlement Challenges The Mars Homestead Project began with a simple operational premise: establish a permanent base on Mars to perform high-value scientific and engineering research and then to grow the outpost into a larger, permanent settlement. This vision includes:

Testing manufacturing methods to use Mars resources.
Searching for past and present life on Mars.
Conducting basic science research to gain new knowledge about the history of the solar system.
Performing scientific research to use Martian resources to support human life.Maximum Flexibility vs. Mass Production The first Mars settlement will face slow and limited communications with Earth. This will require a great deal of self-sufficiency in developing tools and structures. This situation will require flexible small-scale manufacturing and creative engineers skilled machinists capable of both high-tech and low-tech manufacturing—the equivalent of medieval blacksmiths.

Worker Productivity Because the first crews to Mars will most likely be small—growing from 4 to 8 to 12 people initially—the crew must, of necessity comprise individuals capable of multitasking in a variety of disciplines. This would include civil engineering, life support systems, medical science, botany, microbiology, mechanical engineering, laboratory science, and, especially, simple mechanical maintenance. Such multitasking necessarily implies high worker productivity and proficiency across multiple disciplines. Illnesses or deaths will leave the crew short of vital skills and will necessarily result in emotional and social strain among the crew, though obviously they will have support from experts on Earth. This support would include redesigning equipment on Earth, and transmitting the new designs to be manufactured on Mars.

Limited Earth-Mars Transportation Many high-technology items will need to be flown to Mars from Earth, such as nuclear reactors and specialized laboratory equipment. The settlers must be able to manufacture low-technology, high-mass materials (e.g. bricks, Fiberglas, or iron) on Mars. We assume no radical advances in propulsion in the near future, and that any incremental advances will be used to reduce the cost rather than to increase the mass delivered to Mars. In addition, the orbital mechanics of Earth and Mars dictate that flights only occur during the launch windows every two and one-seventh Earth years. Such potential delays mean that several fundamental requirements must be met:

Earth-Mars cargo support flights must be restricted to high-cost, high-technology equipment.
Mission-critical equipment sent from Earth must be highly reliable.
The crew must have the capability to manufacture simple but necessary materials or equipment on-site.Unknowns While any exploration or settlement crew is unlikely to encounter dragons or hostile natives, they will still have to cope with “unknown unknowns” related to interactions between people or equipment and the Martian environment, including the thin atmosphere, soil chemistry, low gravity, sub-arctic temperatures, radiation, low magnetic fields, microbial-natives, dust, and weather. Such unknowns will impact settlers’ efforts to adapt Earth-based mining, refining, and manufacturing to Mars, the safety and reliability of equipment, and the overall cost of establishing the settlement.

In addition to the unknowns, one advantage of a one-way long term mission is the possibility of discovering native Martian pathogens. To help alleviate the public fear of transmission of Martians germs to Earth a one-way mission would serve as a method of temporary quarantine to determine if such pathogens pose a serious risk to humans. In the likelihood that such pathogens exist, the initial crew would have to stay on Mars indefinitely.

4. Martian Engineering Constraints/Solutions

Mars presents any future builders with a variety of serious challenges and constraints, from near-vacuum atmospheric conditions to sub-zero temperatures lower than anything experienced in Antarctica.

Table 1 below summarizes some of the highlighted differences between the two planets. Given these extremes and constraints, it is important for any future expedition to identify and budget for the resources it will have available upon arrival. To build a permanent habitation, a settlement expedition will have the tools and equipment aboard the arriving spacecraft (most likely several vehicles, some arriving before the crew), local materials (meaning the land, water, and atmospheric components of the planet Mars), and the human beings and robots making up the crew.

Table 1. Planetary Comparisons Between Earth and Mars.

Earth Mars Distance from Sun 150 million km 225 million km Diameter 12,756 km 6,786 km Axial Tilt 23.5° 25° Length of Year 365.25 Earth Days 687 Earth Days Length of Days 24 hours 24 hours 37 minutes Gravity 1 g .38 g Temperature Range -88°C to 58°C -127°C to 17°C Atmospheric Pressure 1013 mb (avg.) 7 mb (avg.) Atmospheric Gases 78% N2, 21% O2 95% CO2 Polar Ice Caps Water Ice Water Ice and Dry Ice (CO2) Highest Point Mount Everest – 8.848 km above sea level Olympus Mons –27 km above Martian avg. Lowest Point Marianas Trench – 11.022 km below sea level Hellas Basin – 4 km below Martian average Imported ResourcesFor the purposes of the original study, the team estimated a total arrival mass of 250 metric tons (tonnes) of cargo. Within this mass would be:

Crew – Increasing crew size from 4 to 8 to 12 people, to make on-site decisions, set up and test and repair equipment, and perform many non-repetitive assembly tasks. Having people on Mars is the whole purpose for going.Robotic Equipment / Robots – Both general purpose and dedicated robotic systems for the majority of repetitive tasks.

Food and Shelter – Temporary living quarters, life support, and food necessary to support that labor until a permanent habitat is established.

Power System – including three nuclear reactors providing industrial heating and up to 400 kilowatts (kW) of electrical power, and the cables and other components needed to distribute the power throughout the settlement.

Construction Equipment – such as tractors, dump trailers, drag lines, sifting equipment, “fork lifts”, etc. Initial Mining, Refining, and Manufacturing Equipment—to make gases, chemicals, metals, plastics, ceramics, masonry, glass out of the local atmospheric and regolith materials at hand. In some cases, the manufacturing equipment can be bootstrapped to make more capable manufacturing equipment once on-site.

High-Tech / Low-Mass Items – Any items that would be difficult to manufacture initially on Mars, such as sensors, computers, cameras, radios, other electronics, bearings, precision tools, small valves, medicines, medical devices, and small high-precision mechanical devices.

Scavenged Equipment – Anything that can be re-used from the Mars landing craft, whether designed to be reused in advance, or cannibalized after the fact. These include avionics, computers, control systems, wiring, actuators, sensors, nylon from parachutes, sheet metals, tanks, piping, etc.

Local Resources The “mining” equipment for the first Mars settlement must also include air miners that will ingest material from the Martian atmosphere, which consists of 95.3% carbon dioxide (CO2), 2.7% N2, 1.6% Ar, 0.15% O2, and 0.03% water vapor (H2O) at a pressure around 7 millibars (mbar). After collecting this material, the air miners will use standard, existing chemical processes to create oxygen, habitat buffer gases (N2/Ar mix), methane (CH4), and hydrogen (H2) fuel, longer-chain hydrocarbons, and plastics (including epoxy). Depending on the amount of water available in the local ground or atmosphere, Martian water also could used to nourish plants in the settlement’s greenhouse. In addition to air mining, a similar process will be performed with available local resources in the Martian rock and regolith through ore beneficiation, that is, the crushing and separating ore into valuable substances or waste by any of a variety of techniques, (Petrov, 2004).4. Construction

Mining is only the first step in building the settlement. Once raw materials are obtained, the settlement structure can be built. Due to the extreme cost of importing materials and equipment, relying on habitats brought entirely from Earth is an unsustainable strategy, unless there are revolutionary advances in transportation or manufacturing.

The Mars Homestead Project plan provides efficiency in transportation, infrastructure, safety, and ease of expansion. As a two-avenue structure, the “Linear City” of the Mars settlement will have separately pressurized segments with inflatable modules or regolith-supported masonry to keep the utilities, such as air, water, and power distribution following the “streets” of the city in sub-floor panels beneath the floors.

The team agreed that excavating to build the settlement was much simpler than tunneling for the reasons described in Table 2, below.

Table 2. Comparative Advantages Of Excavation Vs. Tunneling.

Excavation and Covering Tunneling Excavation is optional, as long as firm soil is reached Excavation and covering necessary for entrance area and extraction of raw materials Can be located in most any terrain Prefer a hill or vertical entrance to reach solid rock Building the cover may be done accurately and safely Suitable for many soil types, use sintering for needed strength Relies on strength of rocks above Can fragment rock and permafrost using chemical explosives Requires cutting of solid rock Lower precision requirementThe estimated work will require 20 man-weeks of work to excavate, based on conservative estimates. Small domes and vaults can be built in two days on Earth. As a conservative estimate, the project team assumed that it would take three times as long to do the work on Mars, including arches and walls. Each unit would take two to four man-weeks to complete. The large vaults are twice as big, so they would most likely take eight man-weeks each. The large dome will require special construction methods, so the team assumed an assembly time of 50 man-weeks. The total amount of time required to perform masonry work would be 298 man-weeks.

Given the design of the team’s settlement, summarized in Table 3, and the constraints inherent in building on Mars, we estimated the total construction time to break down in Table 4.

Given an available building staff of four individuals, the entire settlement construction effort would take 560 man-weeks, with an additional 182 man-weeks for safety and helping the engineers install inflatable modules, airlocks, doors, windows, skylights.

Table 3. Summary Of Masonry Structures

Table 4. Construction Time

As the land is being leveled for development, the settlers will use the excavated regolith (dirt) as raw material to make brick, glass, and metal. The emphasis of this settlement will be on using local materials as much as possible to complete construction of a habitat. Continuing to rely on habitats brought from Earth is an unsustainable strategy. Therefore, settlers must maximize their use of Martian materials and simple, well understood, and tested building techniques.

Antique as well as modern methods of construction would be used to build the first Mars settlement. Ancient methods of construction would include masonry work, while modern methods would rigid cylinders made by winding fiberglass; sheet metal would be used where practical; and inflatable structures with rigid internal floors and partitions could be included as well.

The masonry structures would be based on bricks sintered from Martian regolith, reinforced with glass fibers if needed. If that is not practical, the masonry blocks could be glass blocks, fused basalt, or cut stone. Brick manufacturing would require some 2,200 cubic meters of material, which can be obtained from the regolith excavated from the hill. Heat from the nuclear reactors can pre-heat the kiln needed to fire the brick, with the final temperature reached by electric heat or burning chemical fuel produced from the CO2 atmosphere. There will be two kilns of 1.5 cubic meters’ capacity each, with a firing of time 8 hours. Given two batches per day and 6 cubic meters of brick being processed per day, it will take 370 days to make all of the brick required to build the settlement. Given the simplicity of this automated process, human intervention will be required only to maintain the equipment. A total of 20 man-weeks will be required for brick manufacturing. After the bricks are manufactured, the team must start assembling their new home. This will require a variety of different-sized vaults to achieve the size and comfort level required by the inhabitants.

5. Better Martian Living Spaces

Given the known and potential unknown constraints on future human explorers, the study members believed that it was not enough to build a survivable Martian habitat; priority was given to building pleasant, permanent habitations on or under the Martian surface. As noted earlier, the settlers will use the temporary shelter of their arriving spacecraft until construction of the first phase is completed. The sooner settlers are able to establish a homelike environment for themselves, the sooner we can save costs and risks of frequent return flights. Also, a permanent base can easily support scientific exploration, while leading to the true goal of settlement for large numbers of people, with animals and plants.

5.1 Vision – The Hillside Settlement The Mars Homestead Project team designed a partially underground, partially exposed facility built largely from local materials. Using a combination of imported and local resources, the Hillside Settlement will be approximately 90% self-sufficient by mass and will provide the settlers with the industrial capabilities they need to explore and settle the frontier.

The team selected Candor Chasma at reference coordinates 69.95W x 6.36S x -4.4km as the site for the Hillside Settlement. This site is part of the Valles Marineris canyon complex and has been photographed by Mars Global Surveyor. It consists of a number of mesas suitable for providing shelter as well as room for expansion. The site was chosen primarily for its proximity to several dry riverbed-like features. It is also reasonably close to Pavonis Mons, Olympus Mons, and other features of geologic interest. Site selection and response to the site are key design issues for the first settlement. There are a large number of engineering and logistical challenges to be considered in placing the settlement, (James 1998). The settlement must be located in proximity to geologically varied regions of scientific interest. There must be easily accessible in-situ resources. Low elevation is important to take advantage of higher atmospheric pressure, which aids both in harvesting gases from the atmosphere and landing with parachutes. Locations near the equator offer the highest solar intensity for crops, and access to and from any orbit.

There are many architectural and urbanistic issues to consider as well, (Alexander, 1977). The first permanent habitat will be our first cut into the new frontier. This is a very important step that will have an effect on the future development of the planet. A transplant of a pattern from the homeland in a model such as the “Law of the Indies”, in which the Spanish crown dictated the masterplan of every city in the New World, will not work. There simply won’t be the resources available to impose a predetermined plan that doesn’t account for local conditions. The other extreme of a completely unplanned and pragmatic approach like the one taken by North American settlers is also unrealistic. The base must react to the site within a set of guiding rules.

The site must also provide a real and perceived sense of protection. On Earth, the location of a new settlement has traditionally been dominated by considerations for defense. On Mars there are no natives to defend against, but the need for a psychological sense of protection against a hostile environment is still real. Finally, any settlement needs a symbol that the residents can identify with, a landmark that identifies the structure as home, or a sacred place that will symbolize the founding of the community. It should be recognized that eventually the site of the first settlement will become a place of veneration and pilgrimage.

In the years to come, the Foundation will continue to gather more accurate and detailed information about Mars and almost certainly will reach a much more informed decision about the final site. For the purpose of this project, a site was chosen based on the best available information as of autumn 2004.

Candor Chasma A group of mesas in the middle of Candor Chasma fulfill many of the requirements for a successful site. Candor Chasma is one of the northern branches of Valles Marineris (Figure 3). The elevation of the floor of the canyon is almost 4,800 meters below the planetary mean, offering relatively high atmospheric pressure. The walls of the canyon are about eight kilometers above the base. The panorama of the cliffs and valleys will present a beautiful view for the first settlement. Additionally the mesas themselves present an interesting site, giving the settlement a view in the close range as well. There are relatively flat areas to the north and south of the mesas that can serve as landing areas, where the flight paths to and from orbit will not overfly the settlement.

Figure 3. Candor Chasma, The Hillside Settlement Reference Location Shown On An Elevation Map Of Mars

Figure 4. Initial, “Tuna-Can” Style Temporary Habitats Brought From Earth, Greenhouse, Ascent Craft, And Water Well To Tap Permafrost.

As seen in the site plan, Figure 5, the Hillside Settlement reference design is quite extensive. It provides habitation for 12 people and covers 800 square meters, with greenhouses, fuel, nuclear plants, and manufacturing facilities located outside. Private living spaces, labs, and common areas are situated inside the mesa, with some of the rooms providing views of the outside.

Entrance The main entrance is composed of two pressurized modules: the main entry and a garage. The main entry module consists of two airlocks with multiple egress options. One of the airlocks will provide direct access to the Martian surface for daily exterior activities, such as construction and repair work. The other airlock will be a docking port for rovers, (Petrov, 2005).

Figure 5. Hillside Settlement Reference Design—Site Plan.Social Spaces The settlement will include areas for the entire group to gather in one place. These spaces are arranged along the infrastructure, with vegetation mediating the spaces between humans in a “Chinese garden” fashion. The human activities are located in the center with the trees surrounding them on two sides. This is where the community comes together on a daily basis (Figure 6 and later Figure 9). The space includes the communal kitchen and dining areas. The two bays above the dining area are covered with two-story high barrel vaults marking this as a special subspace of the segment. The second level includes balconies, catwalks, public work spaces, and also spaces for exercise and entertainment. Figure 6 below depicts how vegetation would be used in the floor plans.

Figure 6. Close Up Schematic of Settlement Social Spaces.The Greenhouse The greenhouses are the largest modules of the settlement and are situated on the flat land extending away from the mesa. The greenhouses are built with redundancy in mind: if one unit fails, demand can be covered by adjacent units. Each module has the complete ability to recycle water, air, and nutrients. The waste handling and water purification units are in the greenhouses and their adjacent modules. Note that 100% recycling is not required, since gases, water, and minerals can be extracted from Mars air and soil. Two greenhouses are transparent to take advantage of natural sunlight, and are supplemented with artificial light as needed. The other two greenhouses are opaque, covered with regolith, and artificially lit (Figure 7).

Figure 7. Concept Design For Gravel Bed Hydroponic Greenhouse Interior.Growing food on Mars would be much different from Earth. One extreme difference is the amount of ultraviolet (UV) radiation that reaches the surface of the planet. This is a major problem when trying to grow Martian-based crops. One possible solution would be to create crop plants that are UV tolerant. This would decrease the need for protective UV coating on Martian green houses.

Other photosynthetic producers on Earth have a natural way of resisting UV radiation with no cost to the productivity of photosynthesis. Microalgal groups create mycosporine-like amino acids (MAA) that absorb UV, (Karentz, 1991). This process is very prevalent in the Antarctic regions, where the ozone hole forms annually. The introduction of MAA algae genes into crops might help Martian agro-productivity.

The crops include a variety of vegetables and grains, as well as some non-edible plants grown for their fibers or usefulness in making particle board. Initially, crops will be grown hydroponically, in trays made from local fiberglass or ceramic pots, and filled with gravel. Later, we hope to grow plants in native soils after leaching harmful minerals as needed and adding organic material. Additionally, since some residents plan to spend a considerable number of year, or the rest of their lives on Mars, the greenhouses are deliberately designed for long sight lines, walking, jogging, or for solitude after work hours.

Side-Lit Greenhouse One possible design for a passively heated and cooled greenhouse is shown in Figure 8. It is designed to use minimal electrical energy for heating and cooling and ventilation, especially during emergency conditions.

Figure 8. Side-Lit Greenhouse, With Radiation Shield Canopy.Sunlight is concentrated by moveable mirrors at the left side, and focusing them through side windows. An overhead scaffold holds radiation shielding material (regolith, ice, or any other material) to retain heat. Air ducts and passageways allow warm air convection to other habitat modules to the right, such as workshops, the kitchen, etc. Not shown are curtains which can be closed at night to retain heat when needed, or opened to allow wind cooling, with chimneys for additional convective cooling if needed.

In the event that an extreme emergency makes much of the base unusable and/or limits electrical power, the crew can retreat to these greenhouses and adjacent workshops and kitchen. There they have all the essentials to live and can repair whatever equipment may have caused the problem. This ‘Side Lit” greenhouse was not incorporated in the Hillside Settlement design, but is being used in the follow-on designs.

Using Vegetation as a Fundamental Aspect of Settlement Life Internal vegetation will be an integral part of the Mars settlement’s social structure and sustainability, as it will be used as a symbol, life support component, mediator of exterior views, green belt for breaking up social spaces, and overall mediator of social life, (Alexander, 1997).

As a symbol, vegetation will hold a special place immediately between the main entrance and the formal meeting space, as the settlers will plant trees on arrival. These plants will symbolize hope and the permanence of the settlement. The trees will grow as the settlement expands, and when people arrive from Earth, the first thing they will see as they enter is the grove of trees. These trees could also provide an occasional fruit or nut.

As a life support component, plant-rated greenhouses will optimize atmosphere, light, structure, and safety for specially designed plants. The farmers will plant seedlings and harvest the crops from inside a pressurized area with the aid of robots.

As a mediator of views within the settlement structure, plants will be placed in front of any windows to the outside, allowing settlers to look at the red of Mars through the soothing green of Earth vegetation. This added “touch of home” aids in settler psychology and stability. Additionally, every private suite has a small garden area in front of its window, and connector segments will terminate with small gardens and a window onto Mars. As a green belt, vegetation will separate heavily traveled areas from work spaces.

As a mediator of social life, plant life can be located either at the center of, or on the periphery of, social spaces. Where plants are in the center, the various social spaces are arranged around the periphery and every social space has views through the vegetation to the other social spaces. Those space with plants around the edge are like a “clearing in the woods” or a “Chinese garden”, where the social space is surrounded and protected by trees. The edges of the space will be hidden, thus obscuring the limited size of the space. Finally, the lifecycle of the vegetation will provide seasonal visual changes in the living space, (Alexander, 1977).

Other Humanizing Features In addition to plants, the overall settlement structure will be laid out with human psychology in mind, as it will feature social “spaces” to cover the entire range of human experiences, from the individual to couples to informal subgroups, sub-team meetings, and the entire community.

Figure 9, an image by Phil Smith, depicts large, open, multi-story masonry structures that are buried at the edge of the hillside. Natural sunlight is directed into this area from light shafts above (Figure 10). A Mars settler leans on the bamboo rail and takes in the view, overlooking lush green spaces.

Figure 9. Interior Of Two Story Common Area.As life in our urban society has shown, artificial lighting is not enough to meet human needs. Therefore, the domes where vegetation is housed will have shafts that reach to the surface, as shown in Figure 10, below. There, light is collected by lenses and brought down to an opening in the top of the dome, where it is spread out again by another lens. This segment encloses a total volume of 1,530 cubic meters and has 125 square meters of floor space.

Rigid cylinders are used in the flat, open areas away from the hillside. The smaller, standard-size rigid modules would be wound fiberglass, constructed inside an inflatable construction tent. The larger ones would be sheet metal welded or riveted on-site, outdoors. Most would be covered with at least 1 meter of regolith (dirt). These modules are at the left of the cut-away Figure 10, and top of the site plan, Figure 5. They include: greenhouses, nuclear power ‘balance of plant’ in purple, and some manufacturing spaces.

Buried masonry vaults and domes are used for much of the living space. We excavate into the hillside in the loose talus slope, and build the vaults there. To hold the internal pressure, several meters of regolith (overburden) must be placed over them. Obviously, the masonry must be strong enough to hold the weight of the overburdened, and have buttresses shaped to hold the weight whether they are pressurized or depressurized. To keep the air from leaking, the bricks are glazed and caulked on the inside. In addition, alternating layers of sand and vapor barrier are placed outside the masonry to collect air which does leak, and route it back into the air processing equipment to be recovered. These modules are at the bottom of the site plan, Figure 5, shown with thick walls, also in Figure 5 and at the right of the cut-away, Figure 10. They include the: two-story public space, labs, kitchen, dining area, (Mackenzie, 1987).

Figure 10. Cut-Away View, Greenhouse On Left, Shallow Masonry Covering Inflatable In Center, Deeply Buried Two Story Masonry On Right, Light Collectors In Upper Right.Pressurized Construction Figure 10 also illustrates a good comparison of different construction techniques to handle the internal air pressure.

Masonry is used over inflatable structures at the edge of the hillside, to transition from the deeply buried masonry vaults to the open area. These are simple inflatable cylinders made from thinner fiberglass or cloth or thin sheet metal. They are used inside masonry vaults for protection. The masonry also holds the hillside back and provides radiation protection. These modules are at the middle of the site plan, Figure 5, shown as thick walls with rounded lines inside them, also at the middle of the cut-away, Figure 10. They include: private suites, waste treatment, greenhouse support, main entry, suit room, rover garage, and some manufacturing spaces.

6. Joining Mars Homestead Project

The Mars Homestead Project can use volunteer help as well as material donations and financial assistance to keep projects like this viable. The Mars Foundation manages a number of task forces and sub-projects to continue and further articulate its Earth-based studies for future Martian settlement.

6.1 Prototype Projects The Foundation plans to sponsor prototype projects, which are small projects suitable for local groups, students, university classes. These projects would design or select equipment to facilitate a self-sustaining settlement on Mars. Such activities could include: Other activities include greenhouse experiments, outfitting a single module of the proposed settlement, or developing small robotic projects.

Mars Homestead and Mars Foundation are trademarks of the Mars Institute incorporated in Massachusetts, USA. We can be reached by email at Info@MarsHome.org or on the Internet at http://www.MarsHome.org.

7. Conclusion

The Mars Foundation’s Homestead Project, compared to round-trip missions, is a cost-effective, human-friendly method of settling Mars. With a one-way mission we avoid multiple risks and the costs of return flights. Refining equipment from Earth produces fiberglass, masonry, plastics, and metal construction materials. Semi-automated manufacturing equipment assembles the habitats, laboratories, and greenhouses for permanent use. Thus, we can afford to build a permanent, growing base to both support scientific study, and immediately start settlement. This would cost about the same as three round-trip missions, such as the NASA Design Reference Missions (DRM). The Foundation strongly encourages interested readers of the Journal of Cosmology to join the Mars Homestead project, or suggest complementary projects.
ACKNOWLEDGMENTS: Numerous people helped with the technology and other aspects of the Mars Homestead program, and the specific Hillside Settlement design. They including: Adam Burch, April Andreas, Bruce Mackenzie, Damon Ellender, Frank Crossman, Gary Fisher, Georgi Petrov, Ian O’Neill, Inka Hublitz, Jaime Dorsey, James Burk, James Ghoston, K. Manjunatha, Mike Delaney, Randall Severy, Richard Sylvan, Robert Dyck, Susan Martin, William Johns. Special thanks to Georgi Petrov, Phil Smith, Bryan Versteeg, Adam Burch, and NASA for the images.


REFERENCESAlexander, C. (1977). A Pattern Language. Oxford University Press.

James G., Chamitoff, G., Barker, D. (1998). Resource Utilization and Site Selection for a Self-Sufficient Martian Outpost.” NASA/TM-98-206538.

Karentz, D., McEuen S., Land, M., Dunlap, W. (1991). Survey of mycosporine-like amino acid compounds in Antarctic marine organisms: Potential protection from ultraviolet exposure, Marine Biology, ISBN 0025-3162

Mackenzie, B. (1987). Building Mars Habitats Using Local Material, pg 575 in The Case for Mars III: Strategies for Exploration. Stoker, Carol ed., American Astronautical Society: Science and Technology Series v74.

Petrov, G. (2004). A Permanent Settlement on Mars: The First Cut in the Land of a New Frontier. Master of Architecture Thesis, MIT .

Petrov, G. I., Mackenzie B., Homnick M., and Palaia J. (2005). A Permanent Settlement on Mars: The Architecture of the Mars Homestead Project. Society of Automotive Engineers (SAE) International.

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Looking back at Uranus

Voyager 2 at Uranus 

An artist interpretation of Voyager 2 at Uranus released by NASA in 1981. Uranus would prove to have a much blander appearance than expected. (credit: NASA/JPL)

The Grand Tour: Uranus

by Andrew J. LePage
Monday, January 24, 2011

Sometimes the hardest part of a long journey is just getting started. But even then, problems along the way might prevent you from ever reaching your final destination. This proved to be very true for Uranus, which was visited for the first (and so far only) time by Voyager 2 a quarter century ago on January 24, 1986.

During the early years of the Space Age, as the United States and the Soviet Union were launching their first probes to the Moon and planets, Uranus was not being seriously considered as a near-term target for exploration. Because of its remoteness, the trip time from the Earth to Uranus by conventional chemical propulsion would be over a decade and require enormous rockets to loft tiny payloads. Realistically, Uranus could only be reached directly from Earth by means of nuclear-based or other advanced propulsion systems that would not be available for years or more.

In the end, NASA’s plans for the Grand Tour proved to be too ambitious and far too expensive with an estimated price tag of $900 million (almost $5 billion today).

But in 1965, Gary Flandro, then a NASA summer intern, discovered that as a result of a rare alignment of the outer planets that occurs only once every 176 years, it would be possible to send a probe to Jupiter in the late 1970s and then have it flyby successively more distant planets for a fast reconnaissance of all the outer planets. While the largest rockets available were just capable of sending a respectable payload directly to Jupiter, this giant planet’s gravity would provide the extra boost needed to reach all of the planets beyond with flight times of just years.

In 1969 NASA formally began design of what they called the Grand Tour mission. They envisioned building a set of highly advanced, nuclear-powered probes capable of enduring a decade-long mission—many times longer than had been demonstrated with any earlier spacecraft. In one of the many options considered, a pair of Grand Tour spacecraft would be launched in August 1977. They would reach Jupiter around January 1979, Saturn about August 1980, and finally distant Pluto (still considered a planet then) in December 1985. A second pair of probes would depart the Earth in November 1979 and arrive at Jupiter around March 1981. Jupiter would then slingshot the spacecraft to Uranus in February 1985 and Neptune in February 1988 to complete the Grand Tour.

In the end, NASA’s plans for the Grand Tour proved to be too ambitious and far too expensive with an estimated price tag of $900 million (almost $5 billion today). In 1972 NASA scaled back the mission to have a single pair of Mariner-class spacecraft take advantage of the 1977 launch window to Jupiter and Saturn. Originally designated Mariner Jupiter-Saturn 1977 (MJS 77), this more modest mission was managed by the Jet Propulsion Laboratory (JPL) and could be completed with a flight time of four years at an estimated cost of $250 million. By the time of their launch in the summer of 1977, the MJS 77 spacecraft were renamed Voyager.

In order to preserve as much of the original Grand Tour as possible, NASA also began studies for a Mariner Jupiter-Uranus 1979 (MJU 79) mission. MJU 79 would use modified Voyager spacecraft equipped with upgraded systems and instruments. Later, more ambitious versions of this proposal even included an entry probe. In the end, the MJU 79 proposal was not approved in part because of NASA’s ever-tightening budgets in the post-Apollo era.

Even after the cancellation MJU 79, NASA still had a chance of getting a mission to Uranus, albeit a very slim chance. It was possible to have one of the Voyagers continue on to Uranus after its encounter with Saturn, assuming that it had enough propellant left and its vital systems survived that long. A major driver for getting to Uranus was Saturn’s largest moon, Titan (see “The Mysteries of Titan”, The Space Review, November 8, 2010). Mysterious Titan was a prime target for exploration and a close encounter by one of the Voyagers was a mission requirement. Unfortunately, there were no trajectories at that time that allowed a close pass by Titan while preserving the option to continue on to Uranus. In the end it was decided that if the first Voyager spacecraft successfully completed its objectives at Titan in November 1980, the second spacecraft would be directed to follow a trajectory past Saturn in August 1981 that preserved the option to flyby Uranus in late January of 1986. But if the first Voyager failed, the second would instead fly an alternative course that allowed it to flyby Titan with no chance of any subsequent planetary encounters.

MJS-77 illustration 

A NASA rendering released around 1976 of a Mariner Jupiter-Saturn 1977 (later called Voyager) spacecraft exercising the Uranus option. (credit: NASA)

The Voyagers

Even though they were less sophisticated than the originally proposed Grand Tour spacecraft, the Voyagers were still the most advanced interplanetary spacecraft of their day. The pair of identical probes had a mass of 825 kilograms (1,820 pounds) each at launch. Their appearance was dominated by a large white dish antenna with a diameter of 3.7 meters (12 feet) that was used to communicate with the Earth. This was mounted on top of the ten-sided main body of Voyager, which was derived from earlier Mariner spacecraft that had explored the inner planets of the Solar System.

While its computers are primitive by today’s standards, they gave the Voyagers much more flexibility than any earlier planetary spacecraft.

All of the spacecraft’s electronic equipment was housed in the various compartments of the main body, including three pairs of redundant reprogrammable computers that controlled all the functions of the spacecraft and its instruments. The most important computer system was the Command Control Subsystem (CCS), which was the heart of Voyager’s control system. Next was the Attitude and Articulation Control Subsystem (AACS), which controlled propulsion, attitude control, and instrument pointing. Finally there was the Flight Data System (FDS), which controlled the instruments, stored data, and prepared all the science and engineering data for transmission back to Earth. While these computers are primitive by today’s standards, they gave the Voyagers much more flexibility than any earlier planetary spacecraft.

Voyager sported a number of appendages. One was a boom carrying a set of three radioisotope thermoelectric generators (RTGs) that supplied Voyager with up to 390 watts of electricity. Opposite the RTGs was another boom with the pointable Science Scan Platform mounted on the end. Various boresighted sensors for infrared radiation, polarimetry, ultraviolet spectroscopy, as well as wide- and narrow-angle cameras were fitted to this platform. Instruments for measuring the electromagnetic fields, particles, and the plasma environment were fixed to the body of the spacecraft. The other appendages on Voyager included a slender 13-meter (43-foot) long boom carrying sensitive magnetometers and a pair of 10-meter (33-foot) whip antennas shared by the plasma wave and planetary radio astronomy instruments.

The Voyagers were launched using the Titan IIIE – Centaur D-1T, which was the most powerful American launch vehicle available after the retirement of the Saturn rockets at the end of the Apollo program. To give Voyager the extra kick needed to get to Jupiter, a Thiokol TE 364-4 solid rocket motor, similar to the type used in the third stage of the Delta as well as other launch vehicles of the day, topped off the launch vehicle.

Uranus 

An image of Uranus acquired by Voyager 2 during its approach in January 1986. (credit: NASA/JPL)

The mission starts

After dealing with a host of last minute issues, Voyager 2 was successfully launched on August 20, 1977. But minor problems would continue to crop up after lift off. About an hour after launch, the boom that carried the Science Scan Platform was suppose to extend but the signal was never received that it had fully deployed. After several attempts to lock the boom in place apparently failed, engineers at JPL suspected the problem was not with the boom but the extension sensor. Test images acquired by the cameras of the spacecraft itself confirmed that the science boom had fully extended to within a fraction of a degree.

Voyager 1 was finally launched on September 5 after a series delays to deal with its own last minute problems. Like its sister, Voyager 1 experienced a number of growing pains after leaving the Earth. Ultimately the problems were resolved and the probes’ computers were reprogrammed as needed to optimize spacecraft performance. In particular, changes to AACS programs and the probes’ cruise attitude led to a significant reduction in hydrazine consumption for attitude control. Combined with near optimum launch dates, excellent launch vehicle performance and accurate navigation, Voyager 2 would now have more than sufficient propellant reserves to reach Uranus.

But with only one balky receiver and no backup, controllers were at risk of losing contact with Voyager 2. The prospects for a mission to Uranus dimmed significantly.

By far the most serious crises experienced by Voyager 2 started on April 5, 1978, when engineers discovered that the primary receiver had failed. As programmed, the CCS had switched to the backup receiver when the problem was detected, but the backup was also found to be faulty. The backup receiver’s tracking loop capacitor was malfunctioning and the receiver was unable to lock onto the Doppler-shifted transmissions from controllers on Earth. When controllers switched back to the primary receiver, it experienced a power surge within 30 minutes and blew a fuse, permanently disabling the receiver.

Over the course of the next week engineers worked feverishly to address the problem. On April 13 Voyager 2 was finally contacted by ground controllers and slowly regained regular contact with the receding probe. But with only one balky receiver and no backup, controllers were at risk of losing contact with Voyager 2. As insurance, on June 23, 1978 Voyager 2 was programmed for a bare bones backup mission to automatically flyby Saturn. By October 12 similar instructions were uploaded for a minimum encounter at Jupiter as a backup. The prospects for a mission to Uranus dimmed significantly.

But as the months and years unfolded, the partially deaf backup receiver continued to function and engineers slowly learned how to predict what frequency to transmit from Earth so that the faulty receiver could accept commands. In the mean time, Voyager 1 made its closest pass by Jupiter on March 5, 1979, with Voyager 2 following on July 9. Both spacecraft met their objectives and returned a treasure trove of images and other scientific data about Jupiter and its system of moons.

After leaving the Jovian system, both Voyagers pushed on to Saturn, with Voyager 1 reaching its distant target on November 13, 1980. After Voyager 1 successfully achieved all its objectives during its close encounter with Titan and Saturn, Voyager 2 was now free to exercise the option to continue on to Uranus. And with the continued good performance of Voyager 2 despite the loss of its primary receiver, Voyager program scientists and engineers even began to examine the option of having Voyager 2 flyby Neptune in August 1989 after its Uranus encounter. If Voyager 2 could survive the dozen years needed to reach this remote world, four out of the five original Grand Tour targets would have been reached by the less sophisticated Voyager 2.

On August 25, 1981, Voyager 2 hit its target 101,000 kilometers (63,000 miles) from Saturn to slingshot on to Uranus. But 100 minutes after closest approach, the Science Scan Platform jammed. Within a couple days, engineers at JPL were able to free the platform but much of the post-flyby data was already lost. In time the problem was traced to excessive use of high slew rates in azimuth that forced lubrication from the actuator’s gears. It was felt that restricting the number of slews and the slew rate of the platform would prevent a recurrence of the problem. If the azimuth actuator seized again, a technique to free it using thermal cycling was developed. But just in case the platform permanently froze in azimuth, the entire spacecraft could be rolled to point the instruments while still using the platform’s elevation actuator. It was estimated that Voyager 2 had enough propellant for 150 such roll maneuvers at Uranus but the Neptune option would be in danger.

Miranda 

This mosaic of Miranda was constructed from images acquired by Voyager 2. (credit: NASA/JPL/USGS)

On to Uranus

During Voyager’s quiet four and a half year cruise from Saturn to Uranus, program scientists and engineers were busy back on Earth preparing for the challenging encounter with Uranus. Because of its greater distance, the solar illumination at Uranus is only one quarter of that at Saturn. The greater distance also meant that Voyager’s transmissions to Earth would also be that much weaker. As a result, much less data could be transmitted from Uranus than either Jupiter or Saturn.

In order to improve the data transmission rate, NASA upgraded its Deep Space Network (DSN) stations. The most aggressive improvements were made to the DSN station near Canberra, Australia, in part because it would have the best view of Uranus from its vantage in the southern hemisphere. The 64-meter (210-foot) antenna usually used for communications with Voyager was electronically linked with two 34-meter (112-foot) antennas at the complex as well as the Parkes 64-meter radio astronomy antenna located 320 kilometers (200 miles) away. The 64-meter antennas at the DSN sites in Goldstone, California, and near Madrid, Spain, were arrayed with a 34-meter antenna at each site to improve reception from Uranus. Voyager 2 would now be capable of transmitting data at a rate as high as 21.6 kilobits per second from Uranus, or just half the rate used at Saturn.

With no serious plans currently being considered to take advantage of the next Jupiter-Uranus alignment at the end of this decade, it will likely be at least another quarter of a century before the next mission to Uranus might be launched.

Because of the flexibility afforded by Voyager’s computers, engineers at JPL were able to upgrade some of the spacecraft’s capabilities remotely. The unused backup FDS on Voyager 2 was reprogrammed to compress raw imaging data. Instead of transmitting the full 8-bit brightness value for each image pixel, only the full brightness value of the first pixel in each row was transmitted, with just the brightness differences saved for the rest of the pixels in the row. This compression technique resulted in an average of only 3 bits per pixel. To protect the compressed data from bit errors during transmission, a Reed-Solomon encoder that was carried on board was used on the compressed images as well as the other science data. Previously images were unencoded and non-imaging science data were passed through one of a redundant pair of Golay encoders also carried by the Voyagers. These steps required significantly more work back on Earth to decode the data and reconstruct the images but they allowed up to 200 images to be transmitted each day.

Because of the dim illumination and dark targets expected at Uranus, the exposure times needed to acquire usable images was much longer than at Saturn. The AACS was reprogrammed to steady Voyager more effectively, resulting in a drift rate of only half an arc minute per minute, or less than a quarter of that experienced at Saturn. While a steady platform was needed for distant observations, images of closer targets would smear during long exposures. The AACS was programmed with a new motion compensation technique that accurately slewed the spacecraft during observations at rates as high as two degrees per minute to compensate for the relative movement between Voyager 2 and a close target.

During its encounter, Voyager 2 viewed Uranus nearly pole on with its rings (which were discovered only months before launch in 1977) and the orbits of its five moons then known looking like a cosmic bulls eye. As a result, only the southern half of Uranus and its moons would be lit. Unlike the situation at Jupiter and Saturn where the close encounters with the planet and various moons took place over the course of a day or more, the close encounters at Uranus would take place in rapid succession over a just a few hours.

In order to deflect its trajectory towards Neptune, Voyager was directed towards a specific aim point 81,600 kilometers (50,700 miles) above the cloud tops of Uranus. The timing of the close encounter events was chosen so that they could be observed from the DSN station in Australia. As luck would have it, this allowed Voyager to pass only 29,000 kilometers (18,000 miles) from the smallest and innermost Uranian moon then known, Miranda. This was the closest Voyager 2 passed by any planet or moon up to this point in its mission.

In case the faulty backup receiver failed before the encounter, Voyager 2 was programmed to automatically execute a barebones backup mission that promised to return at least some data from Uranus. Other backup encounter sequences were also prepared for transmission to Voyager 2 in case of a failure in one of the computers or if the scan platform seized again, as well as a host of other contingencies.

On November 4, 1985, Voyager 2 started its observatory sequence where it created a series of time lapse movies of Uranus and its surroundings. In December Voyager spotted its first new moon—eventually called Puck—inside the orbit of Miranda. On January 10, 1986, Voyager 2 started its faster-paced far encounter sequence. As Voyager moved closer, it became apparent that Uranus had a blander appearance than was expected. Only subtle variations in color and extremely faint cloud features were detectable even after extensive image processing. On January 18 Voyager 2 started returning images that were heavily streaked. The problem was quickly traced to a bad element in the FDS used for image compression. New instructions were uploaded to avoid the faulty element and normal images were received again starting January 21—just three days before closest approach.

Around 10.6 hours before closest approach, Voyager 2 entered Uranus’ magnetosphere, which was first detected remotely via its radio emissions just five days earlier. As Voyager 2 neared Uranus, it continued observations not only of the planet but its five larger moons, which displayed a surprising range of geologic activity. About an hour before closest approach, Voyager 2 flew by Miranda. The image compensation technique worked perfectly and the images returned revealed a rich variety of features across the face of the tiny moon. A total of ten additional moons inside the orbit of Miranda were spotted during approach.

On January 24, 1986, at 17:58:24 UT, Voyager 2 made its closest approach to Uranus and its trajectory was deflected towards Neptune as intended. Voyager continued to make observations for the next month as Uranus receded. In the end, almost 7,000 images and a mass of other scientific data were returned about Uranus, its moons, and its rings, that are still being studied. To this day Voyager 2 is the only spacecraft to have visited Uranus. With no serious plans currently being considered to take advantage of the next Jupiter-Uranus alignment at the end of this decade, it will likely be at least another quarter of a century before the next mission to Uranus might be launched.

Bibliography

Ellis D. Miner, “Voyager 2 and Uranus”, Sky & Telescope, Vol. 70, No. 5, pp 420–423, November 1985.

David Morrison and Jane Samz, Voyages to Jupiter (SP-439), NASA, 1980.

David Morrison, Voyages to Saturn (SP-451), NASA, 1982.

Bruce Murray, Journey in Space: The First Thirty Years of Space Exploration, W.W. Norton & Co., 1989.

Bruce A. Smith, “NASA Reconfigures Voyager 2, Ground Stations for Uranus Flyby”, Aviation Week & Space Technology, Vol. 122, No. 20, pp 65–68, May 20, 1985.

E.C. Stone and E.D. Miner, “The Voyager 2 Encounter with the Uranian System”, Science, Vol. 233, No. 4759, pp 39–43, July 4, 1986.

Voyager to Jupiter and Saturn (SP-420), NASA, 1977.

“Voyager 1986 Press Kit”, Release No. 85-176, NASA, January 1986.

“Voyager 2 Managers Resolve Imagery Problem Before Uranus Encounter”,Aviation Week & Space Technology, Vol. 124, No. 4, pp 24-25, January 27, 1986.


Andrew J. LePage is a physicist and freelance writer specializing in astronomy and the history of spaceflight. When not writing, he works as a Senior Project Scientist at Visidyne, Inc., located in the Boston area. He can be reached at Drew_NBPT@comcast.net.

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