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dada wrote:I disagree with the Mallory/Everest article. "Because it's there" and "the desire to conquer the universe" are not brilliantly eloquent words, they're weak arguments. Dangerous and irresponsible ones, as well.
I see nothing romantic about the struggle with the self. Wanting to prove something to yourself is an inner, private affair. More tragic-comic than romantic.
In the endless winter that is Antarctica, the picture of decadence is a juicy strawberry. Research scientists at the Neumayer III polar station may soon be so lucky as to count the treat—and other fresh fruits and vegetables—as part of their diets: engineers at the German Aerospace Center are currently building them a year-round greenhouse.
Called Eden ISS, the closed-system, 20-foot-long shipping container will head to Antarctica in October. The project is now in its final phase; next month Paul Zabel, the future caretaker of the greenhouse, and his colleagues will begin a trial of the garden in Bremen. In simulated Antarctic isolation, they plan to grow between 30 and 50 different species, including tomatoes, peppers, lettuce and strawberries, as well as herbs such as basil and parsley that could add fresh flavors to the packaged foods that make up the typical diet of an Antarctic scientist. “We are focused on pick-and-eat crops—plants that don't need any postprocessing,” Zabel says.
Cultivating greens in the Antarctic's hostile conditions requires extreme measures—temperatures on the Ekström Ice Shelf can drop to −22 degrees Fahrenheit, and the sun disappears for months at a time. To beat the odds, Zabel has turned to the growing method known as aeroponics, which eliminates the need for soil (greenhouses at the American and Australian stations use this method, too). Instead fruit and veggie plants will sit on racks with their roots hanging in the air, where they receive a spritz of nutrient-rich mist every few minutes. Extra carbon dioxide will be pumped into the 75-degree F greenhouse for enrichment, and 42 LED lamps will be tuned to the red and blue wavelengths that plants thrive on, giving the greenhouse a purplish glow.
Biting into a ripe fruit or vegetable could boost morale for the 10 crew members set to overwinter at Neumayer III next season. But the garden is more than a treat for polar scientists, Zabel says. Ultimately the project is designed to test techniques for efficiently cultivating plant-based food in even more extreme environments, such as on the International Space Station or Mars.
. . .Using materials that shield more efficiently would cut down on weight and cost, but finding the right material takes research and ingenuity. NASA is currently investigating a handful of possibilities that could be used in anything from the spacecraft to the Martian habitat to space suits.
“The best way to stop particle radiation is by running that energetic particle into something that’s a similar size,” said Pellish. “Otherwise, it can be like you’re bouncing a tricycle off a tractor-trailer.”
Because protons and neutrons are similar in size, one element blocks both extremely well—hydrogen, which most commonly exists as just a single proton and an electron. Conveniently, hydrogen is the most abundant element in the universe, and makes up substantial parts of some common compounds, such as water and plastics like polyethylene. Engineers could take advantage of already-required mass by processing the astronauts’ trash into plastic-filled tiles used to bolster radiation protection. Water, already required for the crew, could be stored strategically to create a kind of radiation storm shelter in the spacecraft or habitat. However, this strategy comes with some challenges—the crew would need to use the water and then replace it with recycled water from the advanced life support systems.
Polyethylene, the same plastic commonly found in water bottles and grocery bags, also has potential as a candidate for radiation shielding. It is very high in hydrogen and fairly cheap to produce—however, it’s not strong enough to build a large structure, especially a spacecraft, which goes through high heat and strong forces during launch. And adding polyethylene to a metal structure would add quite a bit of mass, meaning that more fuel would be required for launch.
“We’ve made progress on reducing and shielding against these energetic particles, but we’re still working on finding a material that is a good shield and can act as the primary structure of the spacecraft,” said Sheila Thibeault, a materials researcher at NASA’s Langley Research Center in Hampton, Virginia.
One material in development at NASA has the potential to do both jobs: Hydrogenated boron nitride nanotubes—known as hydrogenated BNNTs—are tiny, nanotubes made of carbon, boron, and nitrogen, with hydrogen interspersed throughout the empty spaces left in between the tubes. Boron is also an excellent absorber secondary neutrons, making hydrogenated BNNTs an ideal shielding material.
“This material is really strong—even at high heat—meaning that it’s great for structure,” said Thibeault.
Remarkably, researchers have successfully made yarn out of BNNTs, so it’s flexible enough to be woven into the fabric of space suits, providing astronauts with significant radiation protection even while they’re performing spacewalks in transit or out on the harsh Martian surface. Though hydrogenated BNNTs are still in development and testing, they have the potential to be one of our key structural and shielding materials in spacecraft, habitats, vehicles, and space suits that will be used on Mars.
Physical shields aren’t the only option for stopping particle radiation from reaching astronauts: Scientists are also exploring the possibility of building force fields. Force fields aren't just the realm of science fiction: Just like Earth’s magnetic field protects us from energetic particles, a relatively small, localized electric or magnetic field would—if strong enough and in the right configuration—create a protective bubble around a spacecraft or habitat. Currently, these fields would take a prohibitive amount of power and structural material to create on a large scale, so more work is needed for them to be feasible.
The risk of health effects can also be reduced in operational ways, such as having a special area of the spacecraft or Mars habitat that could be a radiation storm shelter; preparing spacewalk and research protocols to minimize time outside the more heavily-shielded spacecraft or habitat; and ensuring that astronauts can quickly return indoors in the event of a radiation storm.
Radiation risk mitigation can also be approached from the human body level. Though far off, a medication that would counteract some or all of the health effects of radiation exposure would make it much easier to plan for a safe journey to Mars and back.
“Ultimately, the solution to radiation will have to be a combination of things,” said Pellish. “Some of the solutions are technology we have already, like hydrogen-rich materials, but some of it will necessarily be cutting edge concepts that we haven’t even thought of yet.”
Research into manned spaceflight is shifting from low-Earth orbit to destinations much further away, like Mars and the asteroid belt. But society will have to invent many new technologies before it can plausibly send people to those distances.
Such exploration calls for more-efficient fuels, or much more efficient ion engines. If future missions can create fuel from resources outside Earth's gravity well (from lunar material or asteroids), these efforts won't have to waste so much energy just to get fuel into space in the first place. Missions will also need lightweight materials that can shield astronauts from radiation as their ship leaves Earth's protective magnetic field. Space missions will require major advances in 3D printing, too, so astronauts can create replacements for equipment that breaks down during their long flights.
But more than all of these things, missions beyond low-Earth orbit require artificial gravity. Research into this technology is not only critical for long-distance missions, it would also provide an immediate benefit to manned spaceflight — even before humans venture out of Earth's orbit.
The reason space missions need artificial gravity is clear: humans simply did not evolve to live in zero gravity. For starters, about half of the planet's astronauts already suffer from Space Adaptation Syndrome (SAS), a condition that includes severe nausea and disorientation. Gravity is integral to how the brain works out spatial orientation. The brain gets really confused if it can't find "down."
At least astronauts can overcome SAS in time. The physical effects of long-term weightlessness , however, are much more serious — notably including skeletal deterioration, muscle atrophy, weakened cardiovascular systems and severe vision problems. Artificial gravity could solve all of these problems.
The physics are simple: Make a ship that can withstand one g of force (equivalent to the force of gravity on Earth's surface), then start the ship spinning such that the centripetal force is one g at the edge. That's it. No fancy "Star Trek" technology needs to be invented. The ship just needs to spin. And once it's spinning in the vacuum of space, it requires no additional energy or maintenance to continue.
I put this concept into my novel "The Martian" by making the astronauts' transfer ship spin. This was no mere luxury for the crew. In the novel, they spend 124 days in an Earth-Mars transfer before landing on the Red Planet. If they had spent that time in zero-g, muscle atrophy and weakness would have prevented them from even standing up, let alone doing surface operations. The mission plan would have had to schedule a week of recovery time — an unacceptable sacrifice of surface time during such a mission.
Artificial gravity is easily within reach right now. It would not require a giant wheel-in-space that looks like the cover of a 1950's sci-fi novel. A viable design could be something as simple as a crew compartment attached to a counterweight compartment by a long cable that is initially coiled in a spindle. Attitude thrusters on the compartments could start the ship spinning while the cable uncoiled to its desired length. The centripetal force would keep the cable straight as it lengthened. The compartments would have to withstand one g of force, but humanity has 5,000 years of experience building things that withstand one g of force.
Artificial gravity can play a big role in missions that launch much earlier than humanity's first long-distance voyages. The International Space Station (ISS) is only slated to last until 2024 (and many question whether it can really last beyond 2020). If the next space station were built with artificial gravity in mind, it would be monumentally more efficient.
Imagine a central zero-g compartment with two equally weighted compartments attached to it by long cables. The cables hold the force, and everything is connected through pressurized tunnels. Set the whole station spinning, and the outer compartments can have one g of gravity while the central component remains weightless. This would enable zero-g experimentation (the primary benefit of a space station) while allowing the crew to spend most of their time in gravity.
The crew of ISS has to exercise for two hours every day, one-eighth of their waking lives, just to stave off the harmful effects of weightlessness. The station cost $150 billion to build, which means the world has spent almost $19 billion worth of station time on astronaut exercise regimens.
Put another way, accounting for varying crew sizes over time, ISS has had about 21,000 man-days of astronaut time since its creation. That means the station has lost 42,000 hours of potential space research to this problem. The next space station should deal with it.
Designing a station with artificial gravity would undoubtedly be a daunting task. Space agencies would have to re-examine many reliable technologies under the light of the new forces these tools would have to endure. Space flight would have to take several steps back before moving forward again. But the cost of not having artificial gravity is proving to be massive, and it is an absolute requirement for manned exploration of our solar system to develop this technology. Either space agencies work on it, or they will simply stop advancing.
dada » Mon Feb 19, 2018 3:21 pm wrote:Pretty big obstacles. It does make me wonder if maybe we're going about it all wrong. Maybe another civilization with a different technology would have better luck.
SCIENTISTS FOUND THE IDEAL PLACE TO SIMULATE MARS: OMAN’S DESERT
By Emma Fidel Feb 15, 2018
Scientists from around the world are posting up in the desert for four weeks to figure out how we can explore Mars.
Two hundred scientists from 25 countries are working on a project to simulate the conditions on Mars in southern Oman, where the desert terrain closely resembles the Red Planet. The Austrian Space Forum is leading the experiment, which will test technology including rovers, spacesuits, and a portable greenhouse, for a future manned mission to Earth's neighboring planet.
The simulation started Feb. 5, just one day before Elon Musk's company SpaceX successfully launched its Falcon Heavy rocket. It's now the biggest rocket in operation and a major step in the development of technology needed to get astronauts out of the desert and on their way to Mars.
NASA's Lunar Outpost will Extend Human Presence in Deep Space
As NASA sets its sights on returning to the Moon, and preparing for Mars, the agency is developing new opportunities in lunar orbit to provide the foundation for human exploration deeper into the solar system. For months, the agency has been studying an orbital outpost concept in the vicinity of the Moon with U.S. industry and the International Space Station partners. As part of the fiscal year 2019 budget proposal, NASA is planning to build the Lunar Orbital Platform-Gateway in the 2020s.
The platform will consist of at least a power and propulsion element and habitation, logistics and airlock capabilities. While specific technical and mission capabilities as well as partnership opportunities are under consideration, NASA plans to launch elements of the gateway on the agency's Space Launch System or commercial rockets for assembly in space.
"The Lunar Orbital Platform-Gateway will give us a strategic presence in cislunar space. It will drive our activity with commercial and international partners and help us explore the Moon and its resources," said William Gerstenmaier, associate administrator, Human Exploration and Operations Mission Directorate, at NASA Headquarters in Washington. "We will ultimately translate that experience toward human missions to Mars."
The power and propulsion element will be the initial component of the gateway, and is targeted to launch in 2022. Using advanced high-power solar electric propulsion, the element will maintain the gateway's position and can move the gateway between lunar orbits over its lifetime to maximize science and exploration operations. As part of the agency's public-private partnership work under Next Space Technologies for Exploration Partnerships, or NextSTEP, five companies are completing four-month studies on affordable ways to develop the power and propulsion element. NASA will leverage capabilities and plans of commercial satellite companies to build the next generation of all electric spacecraft.
The power and propulsion element will also provide high-rate and reliable communications for the gateway including space-to-Earth and space-to-lunar uplinks and downlinks, spacecraft-to-spacecraft crosslinks, and support for spacewalk communications. Finally, it also can accommodate an optical communications demonstration - using lasers to transfer large data packages at faster rates than traditional radio frequency systems.
Habitation capabilities launching in 2023 will further enhance our abilities for science, exploration, and partner (commercial and international) use. The gateway's habitation capabilities will be informed by NextSTEP partnerships, and also by studies with the International Space Station partners. With this capability, crew aboard the gateway could live and work in deep space for up to 30 to 60 days at a time.
Crew will also participate in a variety of deep space exploration and commercial activities in the vicinity of the Moon, including possible missions to the lunar surface. NASA also wants to leverage the gateway for scientific investigations near and on the Moon. The agency recently completed a call for abstracts from the global science community, and is hosting a workshop in late February to discuss the unique scientific research the gateway could enable. NASA anticipates the gateway will also support the technology maturation and development of operating concepts needed for missions beyond the Earth and Moon system.
Adding an airlock to the gateway in the future will enable crew to conduct spacewalks, enable science activities and accommodate docking of future elements. NASA is also planning to launch at least one logistics module to the gateway, which will enable cargo resupply deliveries, additional scientific research and technology demonstrations and commercial use.
Following the commercial model the agency pioneered in low-Earth orbit for space station resupply, NASA plans to resupply the gateway through commercial cargo missions. Visiting cargo spacecraft could remotely dock to the gateway between crewed missions.
Drawing on the interests and capabilities of industry and international partners, NASA will develop progressively complex robotic missions to the surface of the Moon with scientific and exploration objectives in advance of a human return. NASA's exploration missions and partnerships will also support the missions that will take humans farther into the solar system than ever before.
NASA's Space Launch System rocket and Orion spacecraft are the backbone of the agency's future in deep space. Momentum continues toward the first integrated launch of the system around the Moon in fiscal year 2020 and a mission with crew by 2023. The agency is also looking at a number of possible public/private partnerships in areas including in-space manufacturing and technologies to extract and process resources from the Moon and Mars, known as in-situ resource utilization.
http://www.moondaily.com/reports/NASAs_Lunar_Outpost_will_Extend_Human_Presence_in_Deep_Space_999.html
The agency is also looking at a number of possible public/private partnerships in areas including in-space manufacturing and technologies to extract and process resources from the Moon and Mars, known as in-situ resource utilization.
The Consul wrote:Capitalism, to me, is a form of psychosis.
External reality is defined exclusively in material terms.
That which cannot be monetized has no value.
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