Статті в журналах з теми "CubeSat Constellation"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: CubeSat Constellation.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 статей у журналах для дослідження на тему "CubeSat Constellation".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте статті в журналах для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
Meftah, Mustapha, Fabrice Boust, Philippe Keckhut, Alain Sarkissian, Thomas Boutéraon, Slimane Bekki, Luc Damé, et al. "INSPIRE-SAT 7, a Second CubeSat to Measure the Earth’s Energy Budget and to Probe the Ionosphere." Remote Sensing 14, no. 1 (January 1, 2022): 186. http://dx.doi.org/10.3390/rs14010186.
Повний текст джерелаАнотація:
INSPIRE-SAT 7 is a French 2-Unit CubeSat (11.5 × 11.5 × 22.7 cm) primarily designed for Earth and Sun observation. INSPIRE-SAT 7 is one of the missions of the International Satellite Program in Research and Education (INSPIRE). Twice the size of a 4 × 4 Rubik’s Cube and weighing about 3 kg, INSPIRE-SAT 7 will be deployed in Low Earth Orbit (LEO) in 2023 to join its sister satellite, UVSQ-SAT. INSPIRE-SAT 7 represents one of the in-orbit demonstrators needed to test how two Earth observation CubeSats in orbit can be utilized to set up a satellite constellation. This new scientific and technological pathfinder CubeSat mission (INSPIRE-SAT 7) uses a multitude of miniaturized sensors on all sides of the CubeSat to measure the Earth’s energy budget components at the top-of-the-atmosphere for climate change studies. INSPIRE-SAT 7 contains also a High-Frequency (HF) payload that will receive HF signals from a ground-based HF transmitter to probe the ionosphere for space weather studies. Finally, this CubeSat is equipped with several technological demonstrators (total solar irradiance sensors, UV sensors to measure solar spectral irradiance, a new Light Fidelity (Li-Fi) wireless communication system, a new versatile telecommunication system suitable for CubeSat). After introducing the objectives of the INSPIRE-SAT 7 mission, we present the satellite definition and the mission concept of operations. We also briefly show the observations made by the UVSQ-SAT CubeSat, and assess how two CubeSats in orbit could improve the information content of their Earth’s energy budget measurements. We conclude by reporting on the potential of future missions enabled by CubeSat constellations.
2
TURCU, Danuț, and Gheorghe Adrian STAN. "PURPOSE OF USING CUBESAT SATELLITE TECHNOLOGIES IN THE MILITARY DOMAIN." STRATEGIES XXI - Security and Defense Faculty 17, no. 1 (November 1, 2021): 272–78. http://dx.doi.org/10.53477/2668-2001-21-34.
Повний текст джерелаАнотація:
The increasing usage of space capabilities in the military domain highly requires the development of Nanosatellite polar constellations. In this paper we will analyze the main features of small satellites constellations that could be useful in military purposes. The Nanosatellite or CubeSat technology aim at miniaturization, high modularity and software defined payload, allowing the functionality of entire military space applications and services portfolio, at major low financial costs, translating its scalability and flexibility into a capability. In addition, the efficient combination between low latency and high throughput bandwidth, integrated in federated mega-constellation architectures, transforms CubeSat satellite networks into resilient platforms for development of advanced technologies (5G, IoT), according with the military requirements standards.
3
Chadalavada, Pardhasai, and Atri Dutta. "Regional CubeSat Constellation Design to Monitor Hurricanes." IEEE Transactions on Geoscience and Remote Sensing 60 (2022): 1–8. http://dx.doi.org/10.1109/tgrs.2021.3124473.
Повний текст джерела
4
Nag, Sreeja, Joseph L. Rios, David Gerhardt, and Camvu Pham. "CubeSat constellation design for air traffic monitoring." Acta Astronautica 128 (November 2016): 180–93. http://dx.doi.org/10.1016/j.actaastro.2016.07.010.
Повний текст джерела
5
Kääb, Andreas, Bas Altena, and Joseph Mascaro. "River-ice and water velocities using the Planet optical cubesat constellation." Hydrology and Earth System Sciences 23, no. 10 (October 22, 2019): 4233–47. http://dx.doi.org/10.5194/hess-23-4233-2019.
Повний текст джерелаАнотація:
Abstract. The PlanetScope constellation consists of ∼150 optical cubesats that are evenly distributed like strings of pearls on two orbital planes, scanning the Earth's land surface once per day with an approximate spatial image resolution of 3 m. Subsequent cubesats on each of the orbital planes image the Earth surface with a nominal time lag of approximately 90 s between them, which produces near-simultaneous image pairs over the across-track overlaps of the cubesat swaths. We exploit this short time lag between subsequent Planet cubesat images to track river ice floes on northern rivers as indicators of water surface velocities. The method is demonstrated for a 60 km long reach of the Amur River in Siberia, and a 200 km long reach of the Yukon River in Alaska. The accuracy of the estimated horizontal surface velocities is of the order of ±0.01 m s−1. The application of our approach is complicated by cloud cover and low sun angles at high latitudes during the periods where rivers typically carry ice floes, and by the fact that the near-simultaneous swath overlaps, by design, do not cover the complete Earth surface. Still, the approach enables direct remote sensing of river surface velocities for numerous cold-region rivers at a number of locations and occasionally several times per year – which is much more frequent and over much larger areas than currently feasible. We find that freeze-up conditions seem to offer ice floes that are generally more suitable for tracking, and over longer time periods, compared with typical ice break-up conditions. The coverage of river velocities obtained could be particularly useful in combination with satellite measurements of river area, and river surface height and slope.
6
Gomez Jenkins, Marco, David Krejci, and Paulo Lozano. "CubeSat constellation management using Ionic Liquid Electrospray Propulsion." Acta Astronautica 151 (October 2018): 243–52. http://dx.doi.org/10.1016/j.actaastro.2018.06.007.
Повний текст джерела
7
Kidd, Chris, Toshi Matsui, William Blackwell, Scott Braun, Robert Leslie, and Zach Griffith. "Precipitation Estimation from the NASA TROPICS Mission: Initial Retrievals and Validation." Remote Sensing 14, no. 13 (June 22, 2022): 2992. http://dx.doi.org/10.3390/rs14132992.
Повний текст джерелаАнотація:
This paper describes the initial results of precipitation estimates from the Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS) Millimeter-wave Sounder (TMS) using the Precipitation Retrieval and Profiling Scheme (PRPS). The TROPICS mission consists of a Pathfinder CubeSat and a constellation of six CubeSats, providing a low-cost solution to the frequent sampling of precipitation systems across the Tropics. The TMS instrument is a 12-channel cross-track scanning radiometer operating at frequencies of 91.655 to 204.8 GHz, providing similar resolutions to current passive microwave sounding instruments. These retrievals showcase the potential of the TMS instrument for precipitation retrievals. The PRPS has been modified for use with the TMS using a database based upon observations from current sounding sensors. The results shown here represent the initial postlaunch version of the retrieval scheme, as analyzed for the Pathfinder CubeSat launched on 30 June 2021. In terms of monthly precipitation estimates, the results fall within the mission specifications and are similar in performance to retrievals from other sounding instruments. At the instantaneous scale, the results are very promising.
8
Tsitas, S. R., and J. Kingston. "6U CubeSat commercial applications." Aeronautical Journal 116, no. 1176 (February 2012): 189–98. http://dx.doi.org/10.1017/s0001924000006692.
Повний текст джерелаАнотація:
AbstractRecent work by Tsitas and Kingston(1)has demonstrated that an 8kg 6U CubeSat can be designed to perform Earth observation missions equivalent to those of 50-150kg microsatellites. Their design is reviewed and its commercial potential is compared to the 156kg RapidEye spacecraft. Three other commercial applications of this design are described. These are: a standard spacecraft for space scientists and astronomers; the spacecraft component of anNnation 5 spectral band disaster monitoring constellation and a night imaging satellite. Nanosatellites should now be considered for commercial missions previously thought to require microsatellites.
9
Mazzarella, Luca, Christopher Lowe, David Lowndes, Siddarth Koduru Joshi, Steve Greenland, Doug McNeil, Cassandra Mercury, Malcolm Macdonald, John Rarity, and Daniel Kuan Li Oi. "QUARC: Quantum Research Cubesat—A Constellation for Quantum Communication." Cryptography 4, no. 1 (February 27, 2020): 7. http://dx.doi.org/10.3390/cryptography4010007.
Повний текст джерелаАнотація:
Quantum key distribution (QKD) offers future proof security based on fundamental laws of physics. Long-distance QKD spanning regions such as the United Kingdom (UK) may employ a constellation of satellites. Small satellites, CubeSats in particular, in low Earth orbit are a relatively low-cost alternative to traditional, large platforms. They allow the deployment of a large number of spacecrafts, ensuring greater coverage and mitigating some of the risk associated with availability due to cloud cover. We present our mission analysis showing how a constellation comprising 15 low-cost 6U CubeSats can be used to form a secure communication backbone for ground-based and metropolitan networks across the UK. We have estimated the monthly key rates at 43 sites across the UK, incorporating local meteorological data, atmospheric channel modelling and orbital parameters. We have optimized the constellation topology for rapid revisit and thus low-latency key distribution.
10
Zanette, Luca, Leonardo Reyneri, and Giuseppe Bruni. "Swarm system for CubeSats." Aircraft Engineering and Aerospace Technology 90, no. 2 (March 5, 2018): 379–89. http://dx.doi.org/10.1108/aeat-07-2016-0119.
Повний текст джерелаАнотація:
Purpose This paper aims to present an innovative system able to establish an inter-satellite communication crosslink and to determine the mutual physical positioning for CubeSats belonging to a swarm. Design/methodology/approach Through a system involving a smart antenna array managed by a beamforming control strategy, every CubeSat of the swarm can measure the direction of arrival (DOA) and the distance (range) to estimate the physical position of the received signal. Moreover, during the transmission phase, the smart antenna shapes the beam to establish a reliable and directive communication link with the other spacecraft and/or with the ground station. Furthermore, the authors introduce a deployable structure fully developed at Politecnico di Torino that is able to increase the external surface of CubeSats: this surface allows to gain the interspace between elements of the smart antenna. Findings As a consequence, the communication crosslink, the directivity and the detection performance of the DOA system in terms of directivity and accuracy are improved. Practical implications Moreover, the deployable structure offers a greater usable surface, so a larger number of solar panels can be used. This guarantees up to 25 W of average power supply for the on-board systems and for transmission on a one-unit (1U) CubeSat (10 × 10 × 10 cm). Originality/value This paper describes the physical implementation of the antenna array system on a 1U CubeSat by using the deployable structure developed. Depending on actuators and ability that every CubeSat disposes, various interaction levels between elements can be achieved, thus making the CubeSat constellation an efficient and valid solution for space missions.
11
Yang, Weicai, Qing Chang, Allison Kealy, Yong Xu, and Tianyi Lan. "A Novel Location-Awareness Method Using CubeSats for Locating the Spot Beam Emitters of Geostationary Communications Satellites." Mathematical Problems in Engineering 2018 (2018): 1–9. http://dx.doi.org/10.1155/2018/8035093.
Повний текст джерелаАнотація:
As more spacecraft are launched into the Geostationary Earth Orbit (GEO) belt, the possibility of fatal collisions or unnecessary interference between spacecraft increases. In this paper, a new location-awareness method that uses CubeSats is proposed to assist with radiofrequency (RF) domain verification by means of awareness and identification of the positions of the spot beam emitters of communications satellites in geostationary orbit. By flying a CubeSat (or a constellation of CubeSats) through the coverage area of a spot beam, the spot beam emitter’s position is identified and the spot beam’s pattern knowledge is characterized. The geometry, the equations of motion of the spacecraft, the measurement process, and the filtering equations in a location system are addressed with respect to the location methods investigated in this study. A realistic scenario in which a CubeSat receives signals from GEO communications satellites is simulated using the Systems Tool Kit (STK). The results of the simulation and the analysis presented in this study provide a thorough verification of the performance of the location-awareness method.
12
Samsuzzaman, Md, Mohammad Tariqul Islam, Salehin Kibria, and Mengu Cho. "BIRDS-1 CubeSat Constellation Using Compact UHF Patch Antenna." IEEE Access 6 (2018): 54282–94. http://dx.doi.org/10.1109/access.2018.2871209.
Повний текст джерела
13
Wang, Zhaocheng, and Enrique R. Vivoni. "Mapping Flash Flood Hazards in Arid Regions Using CubeSats." Remote Sensing 14, no. 17 (August 26, 2022): 4218. http://dx.doi.org/10.3390/rs14174218.
Повний текст джерелаАнотація:
Flash flooding affects a growing number of people and causes billions of dollars in losses each year with the impact often falling disproportionally on underdeveloped regions. To inform post-flood mitigation efforts, it is crucial to determine flash flooding extents, especially for extreme events. Unfortunately, flood hazard mapping has often been limited by a lack of observations with both high spatial and temporal resolution. The CubeSat constellation operated by Planet Labs can fill this key gap in Earth observations by providing 3 m near-daily multispectral imagery at the global scale. In this study, we demonstrate the imaging capabilities of CubeSats for mapping flash flood hazards in arid regions. We selected a severe storm on 13–14 August 2021 that swept through the town of Gila Bend, Arizona, causing severe flood damages, two deaths, and the Declaration of a State of Emergency. We found the spatial extent of flooding can be mapped from CubeSat imagery through comparisons of the near-infrared surface reflectance prior to and after the flash flood event (ΔNIR). The unprecedented spatiotemporal resolution of CubeSat imagery allowed the detection of ponded (ΔNIR ≤ −0.05) and flood-affected (ΔNIR ≥ +0.02) areas that compared remarkably well with the 100-year flood event extent obtained by an independent hydraulic modeling study. Our findings demonstrate that CubeSat imagery provides valuable spatial details on flood hazards and can support post-flood activities such as damage assessments and emergency relief.
14
Cespedes, Adolfo Javier Jara, Bramandika Holy Bagas Pangestu, Akitoshi Hanazawa, and Mengu Cho. "Performance Evaluation of Machine Learning Methods for Anomaly Detection in CubeSat Solar Panels." Applied Sciences 12, no. 17 (August 29, 2022): 8634. http://dx.doi.org/10.3390/app12178634.
Повний текст джерелаАнотація:
CubeSat requirements in terms of size, weight, and power restrict the possibility of having redundant systems. Consequently, telemetry data are the primary way to verify the status of the satellites in operation. The monitoring and interpretation of telemetry parameters relies on the operator’s experience. Therefore, telemetry data analysis is less reliable, considering the data’s complexity. This paper presents a Machine Learning (ML) approach to detecting anomalies in solar panel systems. The main challenge inherited from CubeSat is its capability to perform onboard inference of the ML model. Nowadays, several simple yet powerful ML algorithms for performing anomaly detection are available. This study investigates five ML algorithm candidates, considering classification score, execution time, model size, and power consumption in a constrained computational environment. The pre-processing stage introduces the windowed averaging technique besides standardization and principal component analysis. Furthermore, the paper features the background, bus system, and initial operational data of BIRDS-4, a constellation made of three 1U CubeSats released from the International Space Station in March 2021, with a ML model proposal for future satellite missions.
15
Zeleke, Desalegn Abebaw, and Hae-Dong Kim. "A New Strategy of Satellite Autonomy with Machine Learning for Efficient Resource Utilization of a Standard Performance CubeSat." Aerospace 10, no. 1 (January 13, 2023): 78. http://dx.doi.org/10.3390/aerospace10010078.
Повний текст джерелаАнотація:
A mega constellation of Nano/microsatellites is the contemporary solution for global-level Earth observation demands. However, as most of the images taken by Earth-observing satellites are covered by clouds, storing and downlinking these images results in inefficient utilization of scarce onboard resources and bandwidth. In addition, the trend of making satellite task execution plans by ground operators demands the efforts of experts or simulators to predict the real-time situation of satellites and to decide which tasks should be executed next. Granting controlled autonomy to satellites to perform onboard tasks will boost mission effectiveness. We experimented with granting controlled autonomy for satellites in performing onboard image classification and task scheduling. We designed a convolutional neural network-based binary image classification model with more than 99% accuracy in classifying clear and cloudy images. The model is configured to perform inference in low-performance computers of ordinary Cubesats. Moreover, we designed an autonomous satellite task scheduling mechanism based on reinforcement learning. It performs better than a custom heuristic-based method in scheduling onboard tasks. As a result, the proposed classification and scheduling techniques with machine learning ensured efficient utilization of onboard memory, power, and bandwidth in the highly resource-constrained CubeSat platforms and mission accomplishment of Nano/microsatellite constellations.
16
Romero, Alessandro Gerlinger, and Luiz Carlos Gadelha De Souza. "Stability Evaluation of the SDRE Technique based on Java in a CubeSat Attitude and Orbit Control Subsystem." WSEAS TRANSACTIONS ON SYSTEMS 20 (January 29, 2021): 1–8. http://dx.doi.org/10.37394/23202.2021.20.1.
Повний текст джерелаАнотація:
In 2013, the STRaND (University of Surrey and Surrey Satellite Technology Ltd) and the PhoneSat (NASA) programs attracted the attention of the aerospace community applying commercial off-the-shelf smartphones in CubeSats. Both programs deployed CubeSats using smartphones based on Google's Android, in which application development is mainly based on Java programming language. Some of these CubeSats had actuators, e.g., STRaND-1 had three reaction wheels mounted in an orthogonal configuration to provide three-axis control, whereas PhoneSat 2.0 beta had magnetorquers to de-tumble the spacecraft. Taking into account a CubeSat that runs Android operating system (based on a smartphone), it is natural to evaluate the attitude and orbit control subsystem (AOCS) based on Java. Elsewhere, we shown State-Dependent Riccati Equation (SDRE) is a feasible non-linear control technique that can be applied in such CubeSats using Java. Moreover, we shown, through simulation using a Monte Carlo perturbation model, SDRE provides better performance than the PID controller, a linear control technique. In this paper, we tackle the next fundamental problem: stability. We evaluate stability from two perspectives: (1) parametric uncertainty of the inertia tensor and (2) a Monte Carlo perturbation model based on a uniform attitude probability distribution. Through the combination of these two perspectives, we grasp the stability properties of SDRE in a broader sense. In order to handle the uncertainty appropriately, we combine SDRE with H∞. The Nanosatellite Constellation for Environmental Data Collection (CONASAT), a CubeSat from the Brazilian National Institute for Space Research (INPE), provided the nominal parameters for the simulations. The initial results of the simulations shown that the SDRE controller is stable to ± 20% uncertainty in the inertia tensor for attitudes uniformly distributed and angular velocity up to 0.15 radians/second.
17
Braga, J., O. S. C. Durão, M. Castro, F. D’Amico, P. E. Stecchini, S. Amirábile, F. Gonzalez Blanco, et al. "LECX: a cubesat experiment to detect and localize cosmic explosions in hard X-rays." Monthly Notices of the Royal Astronomical Society 493, no. 4 (February 20, 2020): 4852–60. http://dx.doi.org/10.1093/mnras/staa500.
Повний текст джерелаАнотація:
ABSTRACT With the advent of the nanosat/cubesat revolution, new opportunities have appeared to develop and launch small (∼1000 cm3), low-cost (∼US$ 1M) experiments in space in very short time frames (∼2 yr). In the field of high-energy astrophysics, in particular, it is a considerable challenge to design instruments with compelling science and competitive capabilities that can fit in very small satellite buses, such as a cubesat platform, and operate them with very limited resources. Here, we describe a hard X-ray (30–200 keV) experiment, LECX (‘Localizador de Explosões Cósmicas de Raios X’ – Locator of X-Ray Cosmic Explosions), that is capable of detecting and localizing within a few degrees events like gamma-ray bursts and other explosive phenomena in a 2U-cubesat platform, at a rate of ∼5 events per year. In the current gravitational wave era of astronomy, a constellation or swarm of small spacecraft carrying instruments such as LECX can be a very cost-effective way to search for electromagnetic counterparts of gravitational wave events produced by the coalescence of compact objects.
18
Niroumand-Jadidi, M., and F. Bovolo. "WATER QUALITY RETRIEVAL AND ALGAL BLOOM DETECTION USING HIGH-RESOLUTION CUBESAT IMAGERY." ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences V-3-2021 (June 17, 2021): 191–95. http://dx.doi.org/10.5194/isprs-annals-v-3-2021-191-2021.
Повний текст джерелаАнотація:
Abstract. Recent advancements in developing small satellites known as CubeSats provide an increasingly viable means of characterizing the dynamics of inland and nearshore waters with an unprecedented combination of high revisits (< 1 day) with a high spatial resolution (meter-scale). Estimation of water quality parameters can benefit from the very high spatiotemporal resolution of CubeSat imagery for monitoring subtle variations and identification of hazardous events like algal blooms. In this study, we present the first study on retrieving lake chlorophyll-a (Chl-a) concentration and detecting algal blooms using imagery acquired by the PlanetScope constellation which is currently the most prominent source of CubeSat data. Moreover, the concentration of total suspended matter (TSM) is retrieved that is an indicator of turbidity. The retrievals are based upon inverting the radiative transfer model. The low spectral resolution (four bands) of PlanetScope imagery poses challenges for such a physics-based inversion due to spectral ambiguities in optically-complex waters like inland waters. To deal with this issue, the number of variable parameters is minimized through inverse modeling. Given the significance of having high-quality water-leaving reflectance for physics-based models, a variable parameter (gdd) is considered to compensate for the atmospheric and sun-glint artifacts. The results compared to the in-situ data indicate high potentials of PlanetScope imagery in retrieving water quality parameters and detection of algal blooms in our case study (Lake Trasimeno, Italy).
19
Meftah, Mustapha, Luc Damé, Philippe Keckhut, Slimane Bekki, Alain Sarkissian, Alain Hauchecorne, Emmanuel Bertran, et al. "UVSQ-SAT, a Pathfinder CubeSat Mission for Observing Essential Climate Variables." Remote Sensing 12, no. 1 (December 26, 2019): 92. http://dx.doi.org/10.3390/rs12010092.
Повний текст джерелаАнотація:
The UltraViolet and infrared Sensors at high Quantum efficiency onboard a small SATellite (UVSQ-SAT) mission aims to demonstrate pioneering technologies for broadband measurement of the Earth’s radiation budget (ERB) and solar spectral irradiance (SSI) in the Herzberg continuum (200–242 nm) using high quantum efficiency ultraviolet and infrared sensors. This research and innovation mission has been initiated by the University of Versailles Saint-Quentin-en-Yvelines (UVSQ) with the support of the International Satellite Program in Research and Education (INSPIRE). The motivation of the UVSQ-SAT mission is to experiment miniaturized remote sensing sensors that could be used in the multi-point observation of Essential Climate Variables (ECV) by a small satellite constellation. UVSQ-SAT represents the first step in this ambitious satellite constellation project which is currently under development under the responsibility of the Laboratory Atmospheres, Environments, Space Observations (LATMOS), with the UVSQ-SAT CubeSat launch planned for 2020/2021. The UVSQ-SAT scientific payload consists of twelve miniaturized thermopile-based radiation sensors for monitoring incoming solar radiation and outgoing terrestrial radiation, four photodiodes that benefit from the intrinsic advantages of Ga 2 O 3 alloy-based sensors made by pulsed laser deposition for measuring solar UV spectral irradiance, and a new three-axis accelerometer/gyroscope/compass for satellite attitude estimation. We present here the scientific objectives of the UVSQ-SAT mission along the concepts and properties of the CubeSat platform and its payload. We also present the results of a numerical simulation study on the spatial reconstruction of the Earth’s radiation budget, on a geographical grid of 1 ° × 1 ° degree latitude-longitude, that could be achieved with UVSQ-SAT for different observation periods.
20
Rastinasab, Vahid, Weidong Hu, and Mohammad Kazem Tahmasebi. "Water Recognition on the Moon by Using THz Heterodyne-Spectrometer for Identifying the Appropriate Locations to Extract Water for Providing Oxygen for Breathing and Fuel for Spaceships’ Propulsion on the Moon with CubeSat." Aerospace 8, no. 7 (July 12, 2021): 186. http://dx.doi.org/10.3390/aerospace8070186.
Повний текст джерелаАнотація:
Asteroid mining offers vital sources for improving human lives and provides opportunities for interplanetary missions and space travel. There are many professional commercial space companies that are only investing billions of dollars on asteroids mining, but prior to that, one condition for asteroid mining could be planetary stations to refuel the pioneers’ spacecraft or human colonies on alien planets; hence, one of the vital sources for these purposes is water. Water can be harvested to split oxygen for breathing and hydrogen for refueling spaceships’ propulsions, and Earth-to-space water payload transporting is extremely expensive; therefore, discovering extraterrestrial water in outer space is economically beneficial. This paper presents a Lunar CubeSat Injector to deliver four 3U CubeSats into Low Lunar Orbit to make a constellation to identify locations of water sources on the Moon by using a THz heterodyne-spectrometer. In sum, this project can help scientists to recognize more water resources for those who will colonize the Moon and for those planning to go beyond it.
21
Kääb, Andreas, Bas Altena, and Joseph Mascaro. "Coseismic displacements of the 14 November 2016 <i>M</i><sub>w</sub> 7.8 Kaikoura, New Zealand, earthquake using the Planet optical cubesat constellation." Natural Hazards and Earth System Sciences 17, no. 5 (May 9, 2017): 627–39. http://dx.doi.org/10.5194/nhess-17-627-2017.
Повний текст джерелаАнотація:
Abstract. Satellite measurements of coseismic displacements are typically based on synthetic aperture radar (SAR) interferometry or amplitude tracking, or based on optical data such as from Landsat, Sentinel-2, SPOT, ASTER, very high-resolution satellites, or air photos. Here, we evaluate a new class of optical satellite images for this purpose – data from cubesats. More specific, we investigate the PlanetScope cubesat constellation for horizontal surface displacements by the 14 November 2016 Mw 7.8 Kaikoura, New Zealand, earthquake. Single PlanetScope scenes are 2–4 m-resolution visible and near-infrared frame images of approximately 20–30 km × 9–15 km in size, acquired in continuous sequence along an orbit of approximately 375–475 km height. From single scenes or mosaics from before and after the earthquake, we observe surface displacements of up to almost 10 m and estimate matching accuracies from PlanetScope data between ±0.25 and ±0.7 pixels (∼ ±0.75 to ±2.0 m), depending on time interval and image product type. Thereby, the most optimistic accuracy estimate of ±0.25 pixels might actually be typical for the final, sun-synchronous, and near-polar-orbit PlanetScope constellation when unrectified data are used for matching. This accuracy, the daily revisit anticipated for the PlanetScope constellation for the entire land surface of Earth, and a number of other features, together offer new possibilities for investigating coseismic and other Earth surface displacements and managing related hazards and disasters, and complement existing SAR and optical methods. For comparison and for a better regional overview we also match the coseismic displacements by the 2016 Kaikoura earthquake using Landsat 8 and Sentinel-2 data.
22
Wilson, Emily L., Vincent J. Riot, A. J. DiGregorio, Guru Ramu, Paul Cleveland, Lance M. Simms, Darrell Carter, Bill Bruner, Jennifer Young, and Geronimo Villanueva. "MiniCarb: a passive, occultation-viewing, 6U CubeSat for observations of CO2, CH4, and H2O." Measurement Science and Technology 33, no. 1 (November 19, 2021): 015902. http://dx.doi.org/10.1088/1361-6501/ac3679.
Повний текст джерелаАнотація:
Abstract We present the final design, environmental testing, and launch history of MiniCarb, a 6U CubeSat developed through a partnership between NASA Goddard Space Flight Center and Lawrence Livermore National Laboratory. MiniCarb’s science payload, developed at Goddard, was an occultation-viewing, passive laser heterodyne radiometer for observing methane, carbon dioxide, and water vapor in Earth’s atmosphere at ∼1.6 µm s−1. MiniCarb’s satellite, developed at Livermore, implemented their CubeSat Next Generation Bus plug-and-play architecture to produce a modular platform that could be tailored to a range of science payloads. Following the launch on 5 December 2019, MiniCarb traveled to the International Space Station and was set into orbit on 1 February 2020 via Northrop Grumman’s Cygnus capsule which deployed MiniCarb with tipoff rotation of about 20° s−1 (significantly higher than the typical rate of 3° s−1 from prior CubeSats), from which the attitude control system was unable to recover resulting in a loss of power. In spite of this early failure, MiniCarb had many successes including rigorous environmental testing, successful deployment of its solar panels, and a successful test of the radio and communication through the Iridium network. This prior work and enticing cost (approximately $2 M for the satellite and $250 K for the payload) makes MiniCarb an ideal candidate for a low-cost and rapid rebuild as a single orbiter or constellation to globally observe key greenhouse gases.
23
Mohammad Zaki, Syazana Basyirah Binti, Mengu Cho, and Nobuyuki Kaya. "Adaptive Array Antenna in Ground Station Control System for Massive LEO CubeSat Constellation Tracking." International Review of Aerospace Engineering (IREASE) 14, no. 2 (April 30, 2021): 97. http://dx.doi.org/10.15866/irease.v14i2.19596.
Повний текст джерела
24
Aldeghi, Carn, Escobar-Wolf, and Groppelli. "Volcano Monitoring from Space Using High-Cadence Planet CubeSat Images Applied to Fuego Volcano, Guatemala." Remote Sensing 11, no. 18 (September 16, 2019): 2151. http://dx.doi.org/10.3390/rs11182151.
Повний текст джерелаАнотація:
Fuego volcano (Guatemala) is one of the most active and hazardous volcanoes in the world. Its persistent activity generates lava flows, pyroclastic density currents (PDCs), and lahars that threaten the surrounding areas and produce frequent morphological change. Fuego’s eruption deposits are often rapidly eroded or remobilized by heavy rains and its constant activity and inaccessible terrain makes ground-based assessment of recent eruptive deposits very challenging. Earth-orbiting satellites can provide unique observations of volcanoes during eruptive activity, when ground-based techniques may be too hazardous, and also during inter-eruptive phases, but have typically been hindered by relatively low spatial and temporal resolution. Here, we use a new source of Earth observation data for volcano monitoring: high resolution (~3 m pixel size) images acquired from a constellation of over 150 CubeSats (‘Doves’) operated by Planet Labs Inc. The Planet Labs constellation provides high spatial resolution at high cadence (<1–72 h), permitting space-based tracking of volcanic activity with unprecedented detail. We show how PlanetScope images collected before, during, and after an eruption can be applied for mapping ash clouds, PDCs, lava flows, or the analysis of morphological change. We assess the utility of the PlanetScope data as a tool for volcano monitoring and rapid deposit mapping that could assist volcanic hazard mitigation efforts in Guatemala and other active volcanic regions.
25
Allahvirdi-Zadeh, Amir, Joseph Awange, Ahmed El-Mowafy, Tong Ding, and Kan Wang. "Stability of CubeSat Clocks and Their Impacts on GNSS Radio Occultation." Remote Sensing 14, no. 2 (January 13, 2022): 362. http://dx.doi.org/10.3390/rs14020362.
Повний текст джерелаАнотація:
Global Navigation Satellite Systems’ radio occultation (GNSS-RO) provides the upper troposphere-lower stratosphere (UTLS) vertical atmospheric profiles that are complementing radiosonde and reanalysis data. Such data are employed in the numerical weather prediction (NWP) models used to forecast global weather as well as in climate change studies. Typically, GNSS-RO operates by remotely sensing the bending angles of an occulting GNSS signal measured by larger low Earth orbit (LEO) satellites. However, these satellites are faced with complexities in their design and costs. CubeSats, on the other hand, are emerging small and cheap satellites; the low prices of building them and the advancements in their components make them favorable for the GNSS-RO. In order to be compatible with GNSS-RO requirements, the clocks of the onboard receivers that are estimated through the precise orbit determination (POD) should have short-term stabilities. This is essential to correctly time tag the excess phase observations used in the derivation of the GNSS-RO UTLS atmospheric profiles. In this study, the stabilities of estimated clocks of a set of CubeSats launched for GNSS-RO in the Spire Global constellation are rigorously analysed and evaluated in comparison to the ultra-stable oscillators (USOs) onboard the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC-2) satellites. Methods for improving their clock stabilities are proposed and tested. The results (i) show improvement of the estimated clocks at the level of several microseconds, which increases their short-term stabilities, (ii) indicate that the quality of the frequency oscillator plays a dominant role in CubeSats’ clock instabilities, and (iii) show that CubeSats’ derived UTLS (i.e., tropopause) atmospheric profiles are comparable to those of COSMIC-2 products and in situ radiosonde observations, which provided external validation products. Different comparisons confirm that CubeSats, even those with unstable onboard clocks, provide high-quality RO profiles, comparable to those of COSMIC-2. The proposed remedies in POD and the advancements of the COTS components, such as chip-scale atomic clocks and better onboard processing units, also present a brighter future for real-time applications that require precise orbits and stable clocks.
26
Filho, Antonio Cassiano Julio, Auro Tikami, Elaine de Souza Ferreira de Paula, Jhonathan Murcia Piñeros, George Favale Fernandes, Lázaro Aparecido Pires Camargo, Carlos Alberto Monteiro Barbosa dos Santos, Walter Abrahão dos Santos, and Kleber Pinheiro Naccarato. "CubeSat Development for Lightning Flashes Detection: RaioSat Project." Journal of Aerospace Technology and Management, no. 12 (November 21, 2020): 80–93. http://dx.doi.org/10.5028/jatm.cab.1161.
Повний текст джерелаАнотація:
Annually, severe weather phenomena are responsible for tens of thousands of deaths and tens of billions of dollars of damage around the world. In Brazil, unlike other hydrometeorological events, severe atmospheric events are random and, therefore, do not have a sociospatial pattern. Because of that, there is a significant motivation to improve the prediction techniques for this kind of events, using high resolution numerical models. A large amount of high-quality observational data is required, including lightning data in a very short-range. In addition, the detection of lightning flashes produced by storms is important for a wide variety of applications and in some areas of scientific research, which include the understanding of the human action on the climate and how the climate change can affect the behavior of storms in long range. One method to monitor the lightning flashes is the implementation of sensors in satellites to obtain data. In this sense, the objective of the RaioSat project is to develop national technology for detecting lightning flashes from the space, in order to complement the existing data from the ground detection network, BrasilDAT. The main objective of this article is to present a methodology for the development of the RaioSat mission including some parts of the preliminary design and operational modes. Additionally, the article describes the expected results and the continuity of the project and a preliminary analysis of a constellation for future projects.
27
Lazreg, Nissen, Omar Ben Bahri, and Kamel Besbes. "Analysis and design of Cubesat constellation for the Mediterranean south costal monitoring against illegal immigration." Advances in Space Research 61, no. 4 (February 2018): 1017–24. http://dx.doi.org/10.1016/j.asr.2017.11.019.
Повний текст джерела
28
Llaveria, David, Juan Francesc Munoz-Martin, Christoph Herbert, Miriam Pablos, Hyuk Park, and Adriano Camps. "Sea Ice Concentration and Sea Ice Extent Mapping with L-Band Microwave Radiometry and GNSS-R Data from the FFSCat Mission Using Neural Networks." Remote Sensing 13, no. 6 (March 17, 2021): 1139. http://dx.doi.org/10.3390/rs13061139.
Повний текст джерелаАнотація:
CubeSat-based Earth Observation missions have emerged in recent times, achieving scientifically valuable data at a moderate cost. FSSCat is a two 6U CubeSats mission, winner of the ESA S3 challenge and overall winner of the 2017 Copernicus Masters Competition, that was launched in September 2020. The first satellite, 3Cat-5/A, carries the FMPL-2 instrument, an L-band microwave radiometer and a GNSS-Reflectometer. This work presents a neural network approach for retrieving sea ice concentration and sea ice extent maps on the Arctic and the Antarctic oceans using FMPL-2 data. The results from the first months of operations are presented and analyzed, and the quality of the retrieved maps is assessed by comparing them with other existing sea ice concentration maps. As compared to OSI SAF products, the overall accuracy for the sea ice extent maps is greater than 97% using MWR data, and up to 99% when using combined GNSS-R and MWR data. In the case of Sea ice concentration, the absolute errors are lower than 5%, with MWR and lower than 3% combining it with the GNSS-R. The total extent area computed using this methodology is close, with 2.5% difference, to those computed by other well consolidated algorithms, such as OSI SAF or NSIDC. The approach presented for estimating sea ice extent and concentration maps is a cost-effective alternative, and using a constellation of CubeSats, it can be further improved.
29
MASKEY, Abhas, Pooja LEPCHA, Hari Ram SHRESTHA, Withanage Dulani CHAMIKA, Tharindu Lakmal Dayarathna MALMADAYALAGE, Makiko KISHIMOTO, Yuta KAKIMOTO, et al. "One Year On-Orbit Results of Improved Bus, LoRa Demonstration and Novel Backplane Mission of a 1U CubeSat Constellation." TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES 65, no. 5 (2022): 213–20. http://dx.doi.org/10.2322/tjsass.65.213.
Повний текст джерела
30
Swartz, William, Steven Lorentz, Stergios Papadakis, Philip Huang, Allan Smith, David Deglau, Yinan Yu, Sonia Reilly, Nolan Reilly, and Donald Anderson. "RAVAN: CubeSat Demonstration for Multi-Point Earth Radiation Budget Measurements." Remote Sensing 11, no. 7 (April 3, 2019): 796. http://dx.doi.org/10.3390/rs11070796.
Повний текст джерелаАнотація:
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) 3U CubeSat mission is a pathfinder to demonstrate technologies for the measurement of Earth’s radiation budget, the quantification of which is critical for predicting the future course of climate change. A specific motivation is the need for lower-cost technology alternatives that could be used for multi-point constellation measurements of Earth outgoing radiation. RAVAN launched 11 November 2016, into a nearly 600-km, Sun-synchronous orbit, and collected data for over 20 months. RAVAN successfully demonstrates two key technologies. The first is the use of vertically aligned carbon nanotubes (VACNTs) as absorbers in broadband radiometers for measuring Earth’s outgoing radiation and the total solar irradiance. VACNT forests are arguably the blackest material known and have an extremely flat spectral response over a wide wavelength range, from the ultraviolet to the far infrared. As radiometer absorbers, they have greater sensitivity for a given time constant and are more compact than traditional cavity absorbers. The second technology demonstrated is a pair of gallium phase-change black body cells that are used as a stable reference to monitor the degradation of RAVAN’s radiometer sensors on orbit. Four radiometers (two VACNT, two cavity), the pair of gallium black bodies, and associated electronics are accommodated in the payload of an agile 3U CubeSat bus that allows for routine solar and deep-space attitude maneuvers, which are essential for calibrating the Earth irradiance measurements. The radiometers show excellent long-term stability over the course of the mission and a high correlation between the VACNT and cavity radiometer technologies. Short-term variability—at greater than the tenths-of-a-Watt/m2 needed for climate accuracy—is a challenge that remains, consistent with insufficient thermal knowledge and control on a 3U CubeSat. There are also VACNT–cavity biases of 3% and 6% in the Total and SW channels, respectively, which would have to be overcome in a future mission. Although one of the black bodies failed after four months, the other provided a repeatable standard for the duration of the project. We present representative measurements from the mission and demonstrate how the radiometer time series can be used to reconstruct outgoing radiation spatial information. Improvements to the technology and approach that would lead to better performance and greater accuracy in future missions are discussed.
31
Paul, Robert F., Yaping Cai, Bin Peng, Wendy H. Yang, Kaiyu Guan, and Evan H. DeLucia. "Spatiotemporal Derivation of Intermittent Ponding in a Maize–Soybean Landscape from Planet Labs CubeSat Images." Remote Sensing 12, no. 12 (June 16, 2020): 1942. http://dx.doi.org/10.3390/rs12121942.
Повний текст джерелаАнотація:
Climate change is increasing the frequency and intensity of heavy precipitation in the US Midwest, overwhelming existing tile drainage, and resulting in temporary soil ponding across the landscape. However, lack of direct observations of the dynamics of temporal soil ponding limits our understanding of its impacts on crop growth and biogeochemical cycling. Satellite remote sensing offers a unique opportunity to observe and analyze this dynamic phenomenon at the landscape scale. Here we analyzed a series of red–green–blue (RGB) and near infrared (NIR) remote sensing images from the Planet Labs CubeSat constellation following a period of heavy precipitation in May 2017 to determine the spatiotemporal characteristics of ponding events in the maize–soybean cropland of Champaign County, Illinois USA. We trained Random Forest algorithms for near-daily images to create binary classifications of surface water versus none, which achieved kappa values around 0.9. We then analyzed the morphology of classification results for connected pixels across space and time and found that 2.5% (5180 ha) of this cropland was classified as water surface at some point during this period. The frequency distribution of areal ponding extent exhibited a log–log relationship; the mean and median areas of ponds were 1231 m2 and 126 m2, respectively, with 26.1% of identified ponds being at the minimum threshold area of 45 m2, and 2.5% of the ponds having an area greater than 104 m2 (1 ha). Ponds lasted for a mean duration of 2.4 ± 1.7 days, and 2.3% of ponds lasted for more than a week. Our results suggest that transient ponding may be significant at the landscape scale and ought to be considered in assessments of crop risk, soil and water conservation, biogeochemistry, and sustainability.
32
Cullingworth, Christopher, and Jan-Peter Muller. "Contemporaneous Monitoring of the Whole Dynamic Earth System from Space, Part I: System Simulation Study Using GEO and Molniya Orbits." Remote Sensing 13, no. 5 (February 26, 2021): 878. http://dx.doi.org/10.3390/rs13050878.
Повний текст джерелаАнотація:
Despite the wealth of data produced by previous and current Earth Observation platforms feeding climate models, weather forecasts, disaster monitoring services and countless other applications, the public still lacks the ability to access a live, true colour, global view of our planet, and nudge them towards a realisation of its fragility. The ideas behind commercialization of Earth photography from space has long been dominated by the analytical value of the imagery. What specific knowledge and actionable intelligence can be garnered from these evermore frequent revisits of the planet’s surface? How can I find a market for this analysis? However, what is rarely considered is what is the educational value of the imagery? As students and children become more aware of our several decades of advance in viewing our current planetary state, we should find mechanisms which serve their curiosity, helping to satisfy our children’s simple quest to explore and learn more about what they are seeing. The following study describes the reasons why current GEO and LEO observation platforms are inadequate to provide truly global RGB coverage on an update time-scale of 5-min and proposes an alternative, low-cost, GEO + Molniya 3U CubeSat constellation to perform such an application.
33
Walczak, Ken, Geza Gyuk, Andrew Kruger, Enoch Byers, and Sigi Huerta. "NITESat: A High Resolution, Full-Color, Light Pollution Imaging Satellite Mission." International Journal of Sustainable Lighting 19, no. 1 (June 28, 2017): 48–55. http://dx.doi.org/10.26607/ijsl.v19i1.68.
Повний текст джерелаАнотація:
The NITESat (Night Imaging and Tracking Experiment Satellite) mission is a 2U CubeSat satellite designed for nighttime Earth imaging to quantify and characterize light pollution across the Midwestern United States. It is accompanied and supported by an array of ground-based light pollution observing stations called GONet (Ground Observing Network). NITESat is a pilot mission testing the potential for a simple and inexpensive (<$500,000) satellite to deliver high-resolution, three-color regional data of artificial light at night. In addition, GONet will form the core of an educational outreach program by establishing an array of all-sky monitors covering the imaging region of the satellite with 20+ full sky light pollution citizen-operated stations. This will provide synchronized data coinciding with the NITESat overpasses as well as providing near continuous night sky quality monitoring. If the initial mission is a success, the potential exists to expand the program into a low cost constellation of satellites capable of delivering global coverage. NITESat is being designed, built and will be operated by the Far Horizons program at the Adler Planetarium in Chicago, Illinois. Far Horizons is a student and volunteer centered program offering hands-on engineering and scientific research opportunities for education.
34
Chen, Qiuyu, Konstantin Ntokas, Björn Linder, Lukas Krasauskas, Manfred Ern, Peter Preusse, Jörn Ungermann, Erich Becker, Martin Kaufmann, and Martin Riese. "Satellite observations of gravity wave momentum flux in the mesosphere and lower thermosphere (MLT): feasibility and requirements." Atmospheric Measurement Techniques 15, no. 23 (December 8, 2022): 7071–103. http://dx.doi.org/10.5194/amt-15-7071-2022.
Повний текст джерелаАнотація:
Abstract. In the recent decade it became evident that we need to revise our picture of how gravity waves (GWs) reach the mesosphere and lower thermosphere (MLT). This has consequences for our understanding not just of the properties of the GWs themselves, but in particular of the global circulation in the MLT. Information on spectral distribution, direction, and zonal mean GW momentum flux is required to test the theoretical and modeling findings. In this study, we propose a constellation of two CubeSats for observing mesoscale GWs in the MLT region by means of temperature limb sounding in order to derive such constraints. Each CubeSat deploys a highly miniaturized spatial heterodyne interferometer (SHI) for the measurement of global oxygen atmospheric band emissions. From these emissions, the 3-D temperature structure can be inferred. We propose obtaining four independent observation tracks by splitting the interferograms in the center and thus gaining two observation tracks for each satellite. We present a feasibility study of this concept based on self-consistent, high-resolution global model data. This yields a full chain of end-to-end (E2E) simulations incorporating (1) orbit simulation, (2) airglow forward modeling, (3) tomographic temperature retrieval, (4) 3-D wave analysis, and (5) GW momentum flux (GWMF) calculation. The simulation performance is evaluated by comparing the retrieved zonal mean GWMF with that computed directly from the model wind data. A major question to be considered in our assessment is the minimum number of tracks required for the derivation of 3-D GW parameters. The main result from our simulations is that the GW polarization relations are still valid in the MLT region and can thus be employed for inferring GWMF from the 3-D temperature distributions. Based on the E2E simulations for gaining zonal mean climatologies of GW momentum flux, we demonstrate that our approach is robust and stable, given a four-track observation geometry and the expected instrument noise under nominal operation conditions. Using phase speed and direction spectra we show also that the properties of individual wave events are recovered when employing four tracks. Finally, we discuss the potential of the proposed observations to address current topics in the GW research. We outline for which investigations ancillary data are required to answer science questions.
35
Bruhn, Fredrik C., Nandinbaatar Tsog, Fabian Kunkel, Oskar Flordal, and Ian Troxel. "Enabling radiation tolerant heterogeneous GPU-based onboard data processing in space." CEAS Space Journal 12, no. 4 (June 15, 2020): 551–64. http://dx.doi.org/10.1007/s12567-020-00321-9.
Повний текст джерелаАнотація:
Abstract The last decade has seen a dramatic increase in small satellite missions for commercial, public, and government intelligence applications. Given the rapid commercialization of constellation-driven services in Earth Observation, situational domain awareness, communications including machine-to-machine interface, exploration etc., small satellites represent an enabling technology for a large growth market generating truly Big Data. Examples of modern sensors that can generate very large amounts of data are optical sensing, hyperspectral, Synthetic Aperture Radar (SAR), and Infrared imaging. Traditional handling and downloading of Big Data from space requires a large onboard mass storage and high bandwidth downlink with a trend towards optical links. Many missions and applications can benefit significantly from onboard cloud computing similarly to Earth-based cloud services. Hence, enabling space systems to provide near real-time data and enable low latency distribution of critical and time sensitive information to users. In addition, the downlink capability can be more effectively utilized by applying more onboard processing to reduce the data and create high value information products. This paper discusses current implementations and roadmap for leveraging high performance computing tools and methods on small satellites with radiation tolerant hardware. This includes runtime analysis with benchmarks of convolutional neural networks and matrix multiplications using industry standard tools (e.g., TensorFlow and PlaidML). In addition, a ½ CubeSat volume unit (0.5U) (10 × 10 × 5 cm3) cloud computing solution, called SpaceCloud™ iX5100 based on AMD 28 nm APU technology is presented as an example of heterogeneous computer solution. An evaluation of the AMD 14 nm Ryzen APU is presented as a candidate for future advanced onboard processing for space vehicles.
36
Milliner, Chris, and Andrea Donnellan. "Using Daily Observations from Planet Labs Satellite Imagery to Separate the Surface Deformation between the 4 July Mw 6.4 Foreshock and 5 July Mw 7.1 Mainshock during the 2019 Ridgecrest Earthquake Sequence." Seismological Research Letters 91, no. 4 (January 22, 2020): 1986–97. http://dx.doi.org/10.1785/0220190271.
Повний текст джерелаАнотація:
Abstract On 4 July 2019, the Ridgecrest earthquake sequence began with a series of foreshocks including an Mw 6.4 event near Searles Valley, California. This was then followed 34 hr later by an Mw 7.1 mainshock located just 15 km to the north, with the earthquake sequence resulting in a complex array of intersecting faults. This earthquake sequence poses several interesting questions including, did the stress changes induced by the Mw 6.4 foreshock trigger the Mw 7.1 mainshock and what possible mechanism(s) could explain the occurrence of widespread secondary faulting surrounding both surface ruptures? However, most of the geodetic data (such as Interferometric Synthetic Aperture Radar, light detection and ranging, and optical satellite imagery) were acquired after both events had occurred making it difficult to discern which surface fractures happened when and their possible triggering mechanism. Here, we provide a dataset composed of high-resolution optical imagery, pixel-value difference maps, .kmz fracturing mapping, and horizontal deformation maps derived from subpixel image correlation, which can uniquely separate the surface fracturing and deformation between the foreshock and mainshock events that can help answer these questions. Separate imaging of the events is made possible by the daily acquisition of optical imagery by the Planet Labs cubesat constellation, which acquired data between the two earthquakes, in the morning of 4 and 5 July, at 11.13 a.m. and 05.12 p.m. PST, respectively, with the images acquired just 40 min after the foreshock and 56 min before the mainshock, respectively. Analysis from this optical imagery reveals the location of surface faulting that allows us to map their spatial extent and determine their timing. These data which we provide here can help guide and validate field survey observations to help understand which faults ruptured when, and constrain slip inversion models for more accurate estimates of stress changes induced by the foreshock imposed on the surrounding faults.
37
Edwards, Chris. "Satellites Downsize for Bigger Constellations." New Electronics 52, no. 8 (April 23, 2019): 24–25. http://dx.doi.org/10.12968/s0047-9624(22)61004-6.
Повний текст джерела
38
Munoz-Martin, Joan Francesc, Lara Fernandez, Adrian Perez, Joan Adrià Ruiz-de-Azua, Hyuk Park, Adriano Camps, Bernardo Carnicero Domínguez, and Massimiliano Pastena. "In-Orbit Validation of the FMPL-2 Instrument—The GNSS-R and L-Band Microwave Radiometer Payload of the FSSCat Mission." Remote Sensing 13, no. 1 (December 31, 2020): 121. http://dx.doi.org/10.3390/rs13010121.
Повний текст джерелаАнотація:
The Flexible Microwave Payload-2 is the GNSS-R and L-band Microwave Radiometer Payload on board 3Cat-5/A, one of the two 6-unit CubeSats of the FSSCat mission, which were successfully launched on 3 September 2020 on Vega flight VV16. The instrument occupies nearly a single unit of the CubeSat, and its goal is to provide sea-ice extension and thickness over the poles, and soil moisture maps at low-moderate resolution over land, which will be downscaled using data from Cosine Hyperscout-2 on board 3Cat-5/B. The spacecrafts are in a 97.5° inclination Sun-synchronous orbit, and both the reflectometer and the radiometer have been successfully executed and validated over both the North and the South poles. This manuscript presents the results and validation of the first data sets collected by the instrument during the first two months of the mission. The results of the validation are showing a radiometric accuracy better than 2 K, and a sensitivity lower than the Kelvin. For the reflectometer, the results are showing that the sea-ice transition can be estimated even at short integration times (40 ms). The presented results shows the potential for Earth Observation missions based on CubeSats, which temporal and spatial resolution can be further increased by means of CubeSat constellations.
39
Cressler, John D. "Silicon-Germanium Electronics and Photonics for Space Systems." ECS Meeting Abstracts MA2022-02, no. 32 (October 9, 2022): 1199. http://dx.doi.org/10.1149/ma2022-02321199mtgabs.
Повний текст джерелаАнотація:
Space has been aptly called the “final frontier” (thank you, Star Trek!). The application needs of the global space and aerospace communities are predictably many and varied, ranging from a diverse set of communications and imaging satellites, to the GPS constellation, to microwave and millimeter-wave (mmW) remote sensing to support weather forecasting and climate science, to exploration of other worlds, which include: the mighty James Webb Space Telescope (probing the origins of the universe), the shadowed polar craters of the Moon (the search for water ice), Mars surface (colonization?), and Europa (the search for extraterrestrial life in the water ocean beneath the 10 km ice cap). While classically, orbital satellites were massive, tough to launch, and extremely expensive (a few $Bs), the current (and rapidly accelerating) trend has swung decidedly towards using relatively low-cost (a few $M) and easy to launch constellations of single or multi-U CubeSats (1U = 10x10x10 cm3) to cost-effectively address the plethora of emerging needs. These days, this has been increasingly supported by commercial space ventures (e.g., SpaceX, BlueOrigin et al., vs. the old gang—NASA and DoD), which are proliferating rapidly. As appealing as space is for visioning fun new science and slick applications, it remains a decidedly unfriendly place to visit. Space is the quintessential “extreme environment,” bathed in intense radiation from both our Sun (high energy electrons and protons trapped by the Earth’s magnetosphere in radiation belts) and the cosmos (GeV energy galactic cosmic rays from supernovae). By way of level setting, a satellite in the most benign Earth orbit, Low Earth Orbit (LEO – 160-1000 km up from the surface), experiences 100,000 rad of ionizing radiation dose over mission life. In comparison, 500 rad will do a person in! That is, we are asking a lot of our electronics in such systems, and given the extreme cost constraints of launch weight, adding a few inches of lead shielding is not the ideal solution! In addition, it is mighty chilly in space (2.73 K = -455°F, the cosmic background), and when the sunlight shines on you, it gets uncomfortably warm, very quickly (e.g., on the surface of the Moon, from -180°C to +120°C from darkness to light, within a few moments). Yep, space is a tough place to do business. As I have long argued [1], SiGe HBT BiCMOS technology provides a unique solution for many of the needs of these emerging space systems, including: 1) extreme levels of performance (multi-hundred GHz) with the SiGe HBT and high integration levels with on-board CMOS, for realizing compelling system functionality/unit volume, at low cost; 2) the rapid improvement of all electronic circuit relevant performance metrics with cooling, with operational capability down into the mK quantum regime (SiGe HBTs love chilly weather!); 3) the ability to operate robustly up to 150-200°C, with modest performance loss; 4) the ability to operate robustly over wide temperature ranges (in principle from mK to 150-200°C); 5) built-in robustness to multi-Mrad total ionizing dose radiation; and 6) built-in heavy ion induced latchup immunity (read: those pesky GeV cosmic rays). Long ago (1990s), the notion of creating a low-cost Si-based electronic + photonic integrated circuit (EPIC) “superchip” was envisioned (Soref), which brought together advanced SiGe HBTs (analog, RF-mmW), CMOS (digital), and Si integrated photonics (with the possible exception of a laser, which could be flipped onto the die worse case). In essence, EPICs are a low-cost, high-yielding, reliable, highly integrated Si platform for putting electrons and light into the same conversation! Clearly this represents a paradigm shift to business as usual. Now, with even more compelling system functionality/unit volume, at low cost. Such an EPIC superchip could in principle satisfy all-comers-of-new-needs. While photonics has long been used in space (think solar cells, imagers), EPICs are new to that space game, but possess great potential for the emergent needs in this new vision of CubeSat/SmallSat driven space systems, including, thing like: LIDAR (spacecraft-to-spacecraft positioning); deep space and within-constellation optical communications (huge data rate improvement); and on-spacecraft high bandwidth data transport (think data center in the sky for instruments that spew out tons of data that need to get back home quickly). This field of EPICs in space is only a few years old, but already much has been learned, and results look very encouraging. In this invited talk, I will highlight the current status and the future trends of using SiGe electronic and photonics in space systems. [1] J.D. Cressler, Proc. IEEE, vol. 93, pp. 1559-1582, 2005. Figure 1
40
Areda, Eyoas Ergetu, Jose Rodrigo Cordova-Alarcon, Hirokazu Masui, and Mengu Cho. "Development of Innovative CubeSat Platform for Mass Production." Applied Sciences 12, no. 18 (September 9, 2022): 9087. http://dx.doi.org/10.3390/app12189087.
Повний текст джерелаАнотація:
With the recent increase in CubeSats’ ability to undertake complex and advanced missions, they are being considered for missions such as constellations, which demand high development efficiency. From a satellite interface perspective, productivity can be maximized by implementing a flexible modular structural platform that promotes easy reconfigurability during the integration and testing phase. Thus, the structural design of a CubeSat plays a crucial role in facilitating the satellite integration process. In most cases, the mechanical interface implemented between the primary load-supporting structure and internal satellite subassemblies affects the speed and efficiency of satellite integration by adding or reducing complexity. Most CubeSat structural designs use stacking techniques to mount PCBs onto the primary structure using stacking rods/screws. As a result, the internal subsystems are interconnected. This conventional interface method is observed to increase the number of structural parts, while increasing complexity during integration. In this study, flexible 3U and 1U CubeSat platforms are developed, based on the slot concept. This innovative mounting design provides a simple method of mounting PCBs into the slots. The concept is evaluated and verified for its feasibility for mass production applications. Count and complexity analysis is carried to evaluate the proposed design against the conventional type of structural interface methods. The assessment reveals that this new concept demonstrates a significant improvement in the efficiency of the mass production process.
41
Santilli, Giancarlo, Cristian Vendittozzi, Chantal Cappelletti, Simone Battistini, and Paolo Gessini. "CubeSat constellations for disaster management in remote areas." Acta Astronautica 145 (April 2018): 11–17. http://dx.doi.org/10.1016/j.actaastro.2017.12.050.
Повний текст джерела
42
Nagel, Gustavo Willy, Evlyn Márcia Leão de Moraes Novo, and Milton Kampel. "Nanosatellites applied to optical Earth observation: a review." Ambiente e Agua - An Interdisciplinary Journal of Applied Science 15, no. 3 (June 3, 2020): 1. http://dx.doi.org/10.4136/ambi-agua.2513.
Повний текст джерелаАнотація:
Nanosatellites and CubeSats were first developed for educational purposes. However, their low cost and short development cycle made nanosatellite constellations an affordable option for observing the Earth by remote sensing, increasing the frequency of high-resolution imagery, which is fundamental for studying and monitoring dynamic processes. In this sense, although still incipient, nanosatellite applications and proposed Earth observation missions are steadily growing in number and scientific fields. There are several initiatives from universities, space agencies and private companies to launch new nanosatellite missions. These initiatives are actively investigating new technologies to improve image quality and studying ways to increase acquisition frequency through the launch of larger constellations. So far, the private sector is leading the development of new missions, with proposals ranging from 12 to more than one thousand nanosatellite constellations. Furthermore, new nanosatellite missions have been proposed to tackle specific applications, such as natural disasters, or to test improvements on nanosatellite spatial, temporal and radiometric resolution. The unprecedented combination of high spatial and temporal resolution from nanosatellite constellations associated with improvement efforts in sensor quality is promising and may represent a trend to replace the era of large satellites for smaller and cheaper nanosatellites. This article first reports on the development and new nanosatellite missions of space agencies, universities and private companies. Then a systematic review of published articles using the most successful private constellation (PlanetScope and Doves) is presented and the principal papers are discussed.
43
Nag, Sreeja, Alan S. Li, and James H. Merrick. "Scheduling algorithms for rapid imaging using agile Cubesat constellations." Advances in Space Research 61, no. 3 (February 2018): 891–913. http://dx.doi.org/10.1016/j.asr.2017.11.010.
Повний текст джерела
44
Parham, J. Brent, Vincent Beukelaers, Lawrence Leung, James Mason, Brian Walsh, and Joshua Semeter. "Leveraging Commercial Cubesat Constellations for Auroral Science: A Case Study." Journal of Geophysical Research: Space Physics 124, no. 5 (May 2019): 3487–500. http://dx.doi.org/10.1029/2018ja025966.
Повний текст джерела
45
Aragon, Bruno, Rasmus Houborg, Kevin Tu, Joshua B. Fisher, and Matthew McCabe. "CubeSats Enable High Spatiotemporal Retrievals of Crop-Water Use for Precision Agriculture." Remote Sensing 10, no. 12 (November 22, 2018): 1867. http://dx.doi.org/10.3390/rs10121867.
Повний текст джерелаАнотація:
Remote sensing based estimation of evapotranspiration (ET) provides a direct accounting of the crop water use. However, the use of satellite data has generally required that a compromise between spatial and temporal resolution is made, i.e., one could obtain low spatial resolution data regularly, or high spatial resolution occasionally. As a consequence, this spatiotemporal trade-off has tended to limit the impact of remote sensing for precision agricultural applications. With the recent emergence of constellations of small CubeSat-based satellite systems, these constraints are rapidly being removed, such that daily 3 m resolution optical data are now a reality for earth observation. Such advances provide an opportunity to develop new earth system monitoring and assessment tools. In this manuscript we evaluate the capacity of CubeSats to advance the estimation of ET via application of the Priestley-Taylor Jet Propulsion Laboratory (PT-JPL) retrieval model. To take advantage of the high-spatiotemporal resolution afforded by these systems, we have integrated a CubeSat derived leaf area index as a forcing variable into PT-JPL, as well as modified key biophysical model parameters. We evaluate model performance over an irrigated farmland in Saudi Arabia using observations from an eddy covariance tower. Crop water use retrievals were also compared against measured irrigation from an in-line flow meter installed within a center-pivot system. To leverage the high spatial resolution of the CubeSat imagery, PT-JPL retrievals were integrated over the source area of the eddy covariance footprint, to allow an equivalent intercomparison. Apart from offering new precision agricultural insights into farm operations and management, the 3 m resolution ET retrievals were shown to explain 86% of the observed variability and provide a relative RMSE of 32.9% for irrigated maize, comparable to previously reported satellite-based retrievals. An observed underestimation was diagnosed as a possible misrepresentation of the local surface moisture status, highlighting the challenge of high-resolution modeling applications for precision agriculture and informing future research directions. .
46
d’Angelo, P., and P. Reinartz. "DIGITAL ELEVATION MODELS FROM STEREO, VIDEO AND MULTI-VIEW IMAGERY CAPTURED BY SMALL SATELLITES." International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B2-2021 (June 28, 2021): 77–82. http://dx.doi.org/10.5194/isprs-archives-xliii-b2-2021-77-2021.
Повний текст джерелаАнотація:
Abstract. Small satellites play an increasing role in earth observation. This article evaluates different possibilities of utilizing data from Planet’s SkySat and PlanetScope satellites constellations for derivation of digital elevation models. While SkySat provides high resolution image data with a ground sampling distance of up to 50 cm, the PlanetScope constellation consisting of Dove 3U cubesats provide images with a resolution of around 4 m. The PlanetScope acquisition strategy was not designed for stereo acquisitions, but for daily acquisition of nadir viewing imagery. Multiple different products can be acquired by the SkySat satellites: Collects covering an area of usually 12 by 6 km, tri-stereo collects and video products with a framerate of 30 Hz. This study evaluates DSM generation using a Semi-Global Matching from multi date stereo pairs for SkySat and PlanetScope, and the dedicated Video and tri-stereo SkySat acquisitions. DSMs obtained by merging many PlanetScope across track stereo pairs show an normalized median deviation against LiDaR first pulse data of 5.2 meter over diverse landcover at the test sites around the city of Terrassa in Catalonia, Spain. SkySat tri-stereo products with 80 cm resolution reach an NMAD of 1.3 m over Terrassa.
47
Salazar, Carlos, Jesus Gonzalez-Llorente, Lorena Cardenas, Javier Mendez, Sonia Rincon, Julian Rodriguez-Ferreira, and Ignacio F. Acero. "Cloud Detection Autonomous System Based on Machine Learning and COTS Components On-Board Small Satellites." Remote Sensing 14, no. 21 (November 6, 2022): 5597. http://dx.doi.org/10.3390/rs14215597.
Повний текст джерелаАнотація:
One of the main applications of small satellites is Earth observation. CubeSats and different kinds of nanosatellites usually form constellations that obtain images mainly using an optical payload. There is a massive amount of data generated by these satellites and a limited capacity of download due to volume and mass constraints that make it difficult to use high-speed communication systems and high-power systems. For this reason, it is important to develop satellites with the autonomy to process data on board. In this way, the limited communication channel can be used efficiently to download relevant images containing the required information. In this paper, a system for the satellite on-board processing of RGB images is proposed, which automatically detects the cloud coverage level to prioritize the images and effectively uses the download time and the mission operation center. The system implements a Convolutional Neural Network (CNN) on a Commercial off-the-Shelf (COTS) microcontroller that receives the image and returns the cloud level (priority). After training, the system was tested on a dataset of 100 images with an accuracy of 0.9 and it was also evaluated with CubeSat images to evaluate the performance of a different image sensor. This implementation contributes to the development of autonomous satellites with processing on board.
48
Azami, M. H., G. Maeda, P. Faure, T. Yamauchi, S. Kim, H. Masui, and Mengu Cho. "BIRDS-2: A Constellation of Joint Global Multi-Nation 1U CubeSats." Journal of Physics: Conference Series 1152 (January 2019): 012008. http://dx.doi.org/10.1088/1742-6596/1152/1/012008.
Повний текст джерела
49
Snow, Adam C., Johnny L. Worthy, Angela den Boer, Luke J. Alexander, Marcus J. Holzinger, and David Spencer. "Optimization of CubeSat Constellations for Uncued Electrooptical Space Object Detection and Tracking." Journal of Spacecraft and Rockets 53, no. 3 (May 2016): 401–19. http://dx.doi.org/10.2514/1.a33386.
Повний текст джерела
50
Kennedy, Andrew K., and Kerri L. Cahoy. "Performance Analysis of Algorithms for Coordination of Earth Observation by CubeSat Constellations." Journal of Aerospace Information Systems 14, no. 8 (January 2017): 451–71. http://dx.doi.org/10.2514/1.i010426.
Повний текст джерела