Автор X, 26.09.2004 00:27:56
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ЦитатаЦитатаТрос из пресловутых нанотрубок диаметром 2 мм должен держать вес в 6-8 тонн. Высота марсостационарной орбиты 17220 км При этом масса троса 36 тонн. А вес с которым он тянет вниз 1800 кг, если сечение троса будет уменьшаться по мере приближения к поверхности то вес его можно снизить. Это не 800 тонн для геостационарной орбиты. Осталось децл, посчитать характеристики ЭРД, для перевода Деймоса на марсостационарную орбиту. A KAK HAC4ET /\YHbI ?[/size]
ЦитатаТрос из пресловутых нанотрубок диаметром 2 мм должен держать вес в 6-8 тонн. Высота марсостационарной орбиты 17220 км При этом масса троса 36 тонн. А вес с которым он тянет вниз 1800 кг, если сечение троса будет уменьшаться по мере приближения к поверхности то вес его можно снизить. Это не 800 тонн для геостационарной орбиты. Осталось децл, посчитать характеристики ЭРД, для перевода Деймоса на марсостационарную орбиту.
ЦитатаКевларовый тросик будет весить несколько десятков килограммов и нам его вполне хватит, тока смысла в нем я невижу. Трос то фигня, а вот коммуникации на 100 км... увольте нереально. Да и чего мелочиться то, берем не Фобос а Деймос, крепим к нему ЭРД помощнее, рабочее тело, сам спутник. Потихоньку вытаскиваем его на марсостационарную орбиту и спускаем с него трос, до поверхности. Это на Земле лифт построить тяжело (большая она), а на Марсе гораздо проще, раз в десять. Вот это использование тросовых систем! А то 100 км. Пойду считать лифт для Марса.
ЦитатаЯ вообще шланг хотел вытянуть, чтобы КК заправлять.А двигать спутники и тянуть с них лифты до поверхности планеты нам пока рановато.А жаль, что у нас нет такого спутника, как Фобос. Думаю, он бы здорово помог в освоении космоса.
ЦитатаА что с ней случилось?
ЦитатаThe nuclear thermal rocket (NTR) is one of the leading propulsion options for future human missions to Mars because of its high specific impulse (1sp is approximately 850-1000 s) capability and its attractive engine thrust-to-weight ratio (approximately 3-10). To stay within the available mass and payload volume limits of a "Magnum" heavy lift vehicle, a high performance propulsion system is required for trans-Mars injection (TMI). An expendable TMI stage, powered by three 15 thousand pounds force (klbf) NTR engines is currently under consideration by NASA for its Design Reference Mission (DRM). However, because of the miniscule burnup of enriched uranium-235 during the Earth departure phase (approximately 10 grams out of 33 kilograms in each NTR core), disposal of the TMI stage and its engines after a single use is a costly and inefficient use of this high performance stage. By reconfiguring the engines for both propulsive thrust and modest power generation (referred to as "bimodal" operation), a robust, multiple burn, "power-rich" stage with propulsive Mars capture and reuse capability is possible. A family of modular bimodal NTR (BNTR) vehicles are described which utilize a common "core" stage powered by three 15 klbf BNTRs that produce 50 kWe of total electrical power for crew life support, an active refrigeration / reliquification system for long term, zero-boiloff liquid hydrogen (LH2) storage, and high data rate communications. An innovative, spine-like "saddle truss" design connects the core stage and payload element and is open underneath to allow supplemental "in-line" propellant tanks and contingency crew consumables to be easily jettisoned to improve vehicle performance. A "modified" DRM using BNTR transfer vehicles requires fewer transportation system elements, reduces IMLEO and mission risk, and simplifies space operations. By taking the next logical step--use of the BNTR for propulsive capture of all payload elements into Mars orbit--the power available in Mars orbit grows to 150 kWe compared to 30 kWe for the DRM. Propulsive capture also eliminates the complex, higher risk aerobraking and capture maneuver which is replaced by a simpler reentry using a standardized, lower mass "aerodescent" shell. The attractiveness of the "all BNTR" option is further increased by the substitution of the lightweight, inflatable "TransHab" module in place of the heavier, hard-shell hab module. Use of TransHab introduces the potential for propulsive recovery and reuse of the BNTR / Earth return vehicle (ERV). It also allows the crew to travel to and from Mars on the same BNTR transfer vehicle thereby cutting the duration of the ERV mission in half--from approximately 4.7 to 2.5 years. Finally, for difficult Mars options, such as Phobos rendezvous and sample return missions, volume (not mass) constraints limit the performance of the "all LH2" BNTR stage. The use of "LOX-augmented" NTR (LANTR) engines, operating at a modest oxygen-to-hydrogen mixture ratio (MR) of 0.5, helps to increase "bulk" propellant density and total thrust during the TMI burn. On all subsequent burns, the bimodal LANTR engines operate on LH2 only (MR=0) to maximize vehicle performance while staying within the mass limits of two Magnum launches.
ЦитатаThe NASA Office of Exploration has been tasked with defining and recommending alternatives for an early 1990's national decision on a focused program of human exploration of the solar system. The Mission Analysis and System Engineering (MASE) group, which is managed by the Exploration Studies Office at the Johnson Space Center, is responsible for coordinating the technical studies necessary for accomplishing such a task. This technical report describes the process that has been developed in a case study approach. The four case studies that were developed in FY88 include: (1) human expedition to Phobos; (2) human expeditions to Mars; (3) lunar observatory; and (4) lunar outpost to early Mars evolution. The final outcome of this effort is a set of programmatic and technical conclusions and recommendations for the following year's work. Volume 2 describes the case study process, the technical results of each of the case studies, and opportunities for additional study. Included in the discussion of each case study is a description of the mission key features and profile. Mission definition and manifesting are detailed, followed by a description of the mission architecture and infrastructure. Systems concepts for the required orbital nodes, transportation systems, and planetary surface systems are discussed. Prerequisite implementation plans resulting from the synthesized case studies are described and in-depth assessments are presented.
ЦитатаThe Office of Exploration (OEXP) at NASA Headquarters has been tasked with defining and recommending alternatives for an early 1990's nationaL decision on a focused program of human exploration of the solar system. The Mission Analysis and System Engineering (MASE) group, which is managed by the Exploration Studies Office at the Lyndon B. Johnson Space Center, is responsible for coordinating the technical studies necessary for accomplishing such a task. This technical report, produced by the MASE, describes the process that has been developed in a case study approach. The four case studies developed in FY88 include: (1) Human Expedition to Phobos; (2) Human Expedition to Mars; (3) Lunar Observatory; and (4) Lunar Outpost to Early Mars Evolution. The final outcome of this effort is a set of programmatic and technical conclusions and recommendations for the following year's work.
ЦитатаSFN пишет: Фобос пустотелый. Он же инопланетная база.
ЦитатаThe manned exploration of Mars is a massive undertaking which requires careful consideration. A mission to the moon of Mars called Phobos as a prelude to manned landings on the Martian surface offers some advantages. One is that the energy requirements, in terms of delta 5, is only slightly higher than going to the Moon's surface. Another is that Phobos is a potential source of water and carbon which could be extracted and processed for life support and cryogenic propellants for use in future missions; thus, Phobos might serve as a base for extended Mars exploration or for exploration of the outer planets. The design of a vehicle for such a mission is the subject of our Aerospace System Design course this year. The materials and equipment needed for the processing plant would be delivered to Phobos in a prior unmanned mission. This study focuses on what it would take to send a crew to Phobos, set up the processing plant for extraction and storage of water and hydrocarbons, conduct scientific experiments, and return safely to Earth. The size, configuration, and subsystems of the vehicle are described in some detail. The spacecraft carries a crew of five and is launched from low Earth orbit in the year 2010. The outbound trajectory to Mars uses a gravitational assisted swing by of Venus and takes eight months to complete. The stay at Phobos is 60 days at which time the crew will be engaged in setting up the processing facility. The crew will then return to Earth orbit after a total mission duration of 656 days. Both stellar and solar observations will be conducted on both legs of the mission. The design of the spacecraft addresses human factors and life science; mission analysis and control; propulsion; power generation and distribution; thermal control; structural analysis; and planetary, solar, and stellar science. A 0.5 g artificial gravity is generated during transit by spinning about the lateral body axis. Nuclear thermal rockets using hydrogen as fuel are sel ected to reduce total launch mass and to shorten the duration of the mission. The nuclear systems also provide the primary electrical power via dual mode operation. The overall spacecraft length is 110 meters and the total mass departing from low Earth orbit is 900 metric tons.
ЦитатаA preliminary design has been developed for a manned mission to the Martian moon Phobos. The spacecraft is to carry a crew of five and will be launched from Low Earth Orbit in the year 2010. The outbound trajectory to Mars uses a gravitational assisted swing-by of Venus and takes eight months to complete. The stay at Phobos is scheduled for 60 days. During this time, the crew will be busily engaged in setting up a prototype fuel processing facility. The vehicle will then return to Earth orbit after a total mission duration of 656 days. The spacecraft is powered by three nuclear thermal rockets which also provide the primary electrical power via dual mode operation. The overall spacecraft length is 110 m, and the total mass departing fr om Low Earth Orbit is 900 metric tons.
ЦитатаScientific exploration opportunities for human missions to the Moon, Phobos, Mars, and an asteroid are addressed. These planetary objects are of prime interest to scientists because they are the accessible, terrestrial-like bodies most likely to be the next destinations for human missions beyond Earth orbit. Three categories of science opportunities are defined and discussed: target science, platform science, and cruise science. Target science is the study of the planetary object and its surroundings (including geological, biological, atmospheric, and fields and particle sciences) to determine the object's natural physical characteristics, planetological history, mode of origin, relation to possible extant or extinct like forms, surface environmental properties, resource potential, and suitability for human bases or outposts. Platform science takes advantage of the target body using it as a site for establishing laboratory facilities and observatories; and cruise science consists of studies conducted by the crew during the voyage to and from a target body. Generic and specific science opportunities for each target are summarized along with listings of straw-man payloads, desired or required precursor information, priorities for initial scientific objectives, and candidate landing sites. An appendix details the potential use of the Moon for astronomical observatories and specialized observatories, and a bibliography compiles recent work on topics relating to human scientific exploration of the Moon, Phobos, Mars, and asteroids. It is concluded that there are a wide variety of scientific exploration opportunities that can be pursued during human missions to planetary targets but that more detailed studies and precursor unmanned missions should be carried out first.
ЦитатаThe Manned Mars Explorer (MME) project responds to the fundamental problems of sending human beings to Mars in a mission scenario and schematic vehicle designs. The mission scenario targets an opposition class Venus inbound swingby for its trajectory with concentration on Phobos and/or Deimos as a staging base for initial and future Mars vicinity operations. Optional vehicles are presented as a comparison using nuclear electric power/propulsion technology. A Manned Planetary Vehicle and Crew Command Vehicle are used to accomplish the targeted mission. The Manned Planetary Vehicle utilizes the mature technology of chemical propulsion combined with an advanced aerobrake, tether and pressurized environment system. The Crew Command Vehicle is the workhorse of the mission performing many different functions including a manned Mars landing, and Phobos rendezvous.
ЦитатаThe problem of orbit transfers from a Mars parking orbit with an inclination of 165 degrees to the Mars Moon is addressed. The transfer can be accomplished using a three impulse transfer. The current 1999 baseline manned Mars mission requires a Mars parking orbit with an inclination of 165 degrees. This orbit inclination is necessary due to the direction of the Mars arrival and departure asymptotes of the interplanetary trajectory. The selection of this inclination for the parking orbit minimized the delta velocity requirements at Mars arrival and departure. This presents a problem in making transfer from this orbit to either Phobos or Deimos since it is a retrograde orbit. It is possible to make this transfer efficiently using a three impulse transfer and an intermediate transfer orbit with a very large apogee altitude. How the intermediate transfer orbit apogee can be determined based on a preselected transfer time, the delta velocities required as a function of transfer time, and the propellant required at a function of mission module weight for a transfer time of 5 days is shown. The data presented is specifically for the 1999 opposition class mission but the methods outlined are applicable to any other mission which requires a high inclination parking orbit.
ЦитатаWe characterize mission profiles for human expeditions to near-Earth asteroids, Venus, and Mars. Near-Earth objects (NEOs) are the closest destinations beyond cis-lunar space and present a compelling target with capabilities already under development by NASA and its partners. We present manned NEO mission options that would require between 90 days and one year. We next consider planetary flyby missions for Venus along the lines of plans that were first drafted during the Apollo program for human exploration of Venus. We also characterize a Mars flyby, and a double-flyby variant that would include close passes to both Venus and Mars. Finally, we consider orbital missions to Venus and Mars with capability for rendezvous with Phobos or Deimos. This would be a truly new class of mission for astronauts and could serve as a precursor to a human landing on Mars. We present launch opportunities, transit time, requisite ΔV, and approximate radiation environment parameters for each mission class. We find that ΔV requirements for each class of mission match near-term chemical propulsion system capabilities.
ЦитатаАнтикосмит пишет: Фобос отличная Марсианская Орбитальная Станция. Да, конечно, для начала надо бы его выесть изнутри, если есть лед.