space sciences and exploration
Ebrahim Amiri; Masoome Khani Chamani; Mahdi Jafari-Nodoshan; Sajjad Ghazanfarinia; Masoud Khoshsima
Articles in Press, Accepted Manuscript, Available Online from 16 December 2023
Abstract
The economic model generally expresses the mechanisms used to earn money from a business, and if it doesnot generate income, its failure will be certain. Therefore, the decision to carry out a mission isnot only based on technical specifications, and besides that, economic profitability is another part ...
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The economic model generally expresses the mechanisms used to earn money from a business, and if it doesnot generate income, its failure will be certain. Therefore, the decision to carry out a mission isnot only based on technical specifications, and besides that, economic profitability is another part of decision-making and will be one of the main factors for commercial investments. Space projects, as wellas moon-mining projects, are no exception to this rule and require an all-round approach to compare financial and technical feasibility. Analyzing the economic feasibility of any project can be summed up in the evaluation of its economic model. In this regard, a model is needed to compare, rank and determine the available options, which is economically justified. In this paper, the economic evaluation of moon-mining based on the materials available on the moon and sending them to the earth is discussed. Materials with economic priority are categorized and selected in a fuzzy evaluation and using an economic model suitable for space mining, an economic evaluation for the business of selling materials on the Earth is carried out and according to economic efficiency, the type of material and also the high-level specifications of the project has been extracted.
Space subsystems design: (navigation, control, structure and…)
Masoud Khoshsima; Mehran Shahryari ; Sajjad Ghazanfarinia; Shiva Emami; yaser saffar
Volume 16, Issue 2 , June 2023, , Pages 79-91
Abstract
The results show that the lidar in cold orbital conditions has a temperature increase of about 38 degrees Celsius due to thermal design. Also, the range of temperature fluctuations before applying thermal design in the cold state of temperature changes in a circuit is about 14 degrees and after designing ...
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The results show that the lidar in cold orbital conditions has a temperature increase of about 38 degrees Celsius due to thermal design. Also, the range of temperature fluctuations before applying thermal design in the cold state of temperature changes in a circuit is about 14 degrees and after designing these fluctuations have been reduced to about 5 degrees. In hot conditions, the temperature conditions have improved a lot after the design and the maximum operating temperature is about 27 degrees the average temperature has decreased by about 22 degrees, while the temperature fluctuations have also decreased by 21 degrees. A significant temperature increase has occurred in the receiver after applying the thermal design in cold conditions, which is still within the allowed range. This is despite the fact that in hot conditions, after applying the thermal design, there was no significant change in the temperature of the receiver. In the case of the reflector, the conditions are completely different, so the minimum temperature in cold conditions has increased by 42 degrees and the maximum temperature has decreased by 7 degrees in hot conditions. In addition, temperature changes have become more uniform in both cases.
Space subsystems design: (navigation, control, structure and…)
Amir Reza Kosari; Alireza Ahmadi; Alireza Sharifi; Masoud Khoshsima
Volume 15, Issue 1 , March 2022, , Pages 21-39
Abstract
Very High Resolution Passive Scan Agile Earth Observation Satellites are able to maneuver around all their three body axes and scan the target area in different directions, simultaneously. The most stringent mid-level requirements which dominate their attitude determination and control subsystem performance ...
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Very High Resolution Passive Scan Agile Earth Observation Satellites are able to maneuver around all their three body axes and scan the target area in different directions, simultaneously. The most stringent mid-level requirements which dominate their attitude determination and control subsystem performance are applied in detumbling and fine pointing modes. These performance requirements are maneuverability, agility, accuracy and stability. In this research, first, we derive the analytical and statistical relationships between quantitative criteria of mid-level requirements and spatial resolution as a high-level mission requirement, next the design drivers of reaction wheels are extracted consequently. Then the size, mass and consuming power of an operational satellite and the reaction wheels torque authority and momentum capacity is guesstimated based on its imaging payload size and specifications.
Space systems design (spacecraft, satellites, space stations and their equipment)
Amirreza Kosari; Asad Saghari; Masoud Khoshsima
Volume 14, Issue 4 , December 2021, , Pages 1-9
Abstract
This article investigates an operational orbit's design and sensitivity analysis for Earth observation (EO) missions in non-sun-synchronous orbits. Sun-synchronous orbits are the primary choice for deploying EO satellites, but in the absence of access to such orbits, alternative options can be considered, ...
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This article investigates an operational orbit's design and sensitivity analysis for Earth observation (EO) missions in non-sun-synchronous orbits. Sun-synchronous orbits are the primary choice for deploying EO satellites, but in the absence of access to such orbits, alternative options can be considered, including multi-sun-synchronous orbits (MSSO) capable of repeating ground track (RGT).In this research, sets of such orbits are designed, taking into account the defined mission and considering the available altitude and inclination of the orbit. To achieve this, a constrained search problem is formulated, considering the constraints related to the characteristics of multi-sun-synchronicity and repeating ground tracks to search for orbit characteristics.Furthermore, to identify the allowable range of injection errors, a sensitivity analysis of the designed orbit's characteristics has been conducted to assess their sensitivity to uncertainties in injection accuracy during a case study investigation.
investigating space radiation
Hamideh Daneshvar; Masoud Khoshsima; Abolfazl Dayyani
Volume 12, Issue 3 , September 2019, , Pages 63-71
Abstract
One of the important issues to be considered in the design of space systems is the attention to the difference between the terrestrial and space environment. This issue changes the design and affects all subsystems of space systems. Radiation damage due to space radiation can cause disturbances in the ...
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One of the important issues to be considered in the design of space systems is the attention to the difference between the terrestrial and space environment. This issue changes the design and affects all subsystems of space systems. Radiation damage due to space radiation can cause disturbances in the functioning of space systems. In this paper, with a computational approach examines the most important radiation damage involving TID, DD and SEU in two satellites that have missions in LEO orbit. The calculations were performed using the OMERE software and finally, a comparison was made between different models for achieving different types of radiation damage.
Behzad Mohasel afshari; Javad Haghshenas; Mohsen Abedi; Masoud Khoshsima
Volume 11, Issue 4 , December 2018, , Pages 23-30
Abstract
In this paper, a precise method for calculating albedo and IR heat flux applied to a satellite is presented. For obtaining albedo heat flux applied to a satellite, a point on the earth’s surface that sun flux reflected at that point and reach to the satellite is obtained, hence albedo heat flux ...
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In this paper, a precise method for calculating albedo and IR heat flux applied to a satellite is presented. For obtaining albedo heat flux applied to a satellite, a point on the earth’s surface that sun flux reflected at that point and reach to the satellite is obtained, hence albedo heat flux reaches to a satellite is obtained as a function of longitude, attitude and longitude. IR heat flux is integration of emitting heat flux for points on the earth surface that in satellite’s view. Atmospheric transparency for calculating albedo and IR heat is considered for sun light and IR spectrum using MODTRAN algorithm using PcModWin software. For a generic LEO satellite, IR and albedo heat fluxes are calculated at a time period and compare with reference values. Obtained heat fluxes are used to obtain temperature variation of satellite’s components during its mission.