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Spacecraft and Missions
Published in Julio Sanchez, Maria P. Canton, William Perrizo, Space Image Processing, 2018
Julio Sanchez, Maria P. Canton
Latitude, time of day, and season are responsible for variations in the characteristics and intensity of light. For each observational task, there is an optimum local sun time. Earth observation satellites are usually placed in orbits designed to provide the best possible illumination and to minimize cloud cover. Often, this time is between 9:30 and 10:30 A.M., local sun time. In order to ensure that the satellite crosses over the same point on earth at the same local time, it must be placed in a sun-synchronous orbit. The result is that the satellite crosses the equator at precisely the same local sun time. This requires that the orbital period be of 24 hours.
Remote Sensing Monitoring of Marine Oil Spills
Published in Lin Mu, Lizhe Wang, Jining Yan, Information Engineering of Emergency Treatment for Marine Oil Spill Accidents, 2019
Lin Mu, Lizhe Wang, Jining Yan
NOAA series. The U.S. NOAA satellites are weather satellites. The orbit is an approximately-circular, sun-synchronous orbit with an altitude of 833 ∼ 870 km and an inclination of 99.092 degrees. The operation cycle is 102 minutes and the revisit cycle 9 days. The satellite passes over the equator at 7:00 a.m. and 2:00 p.m. The sub-satellite point resolution is 1.1 km, and the width of scanning image is 3020 km. Each satellite can cover the earth once every day.
Variation of XCO2 anomaly patterns in the Middle East from OCO-2 satellite data
Published in International Journal of Digital Earth, 2022
Foroogh Golkar, Seyed Mohsen Mousavi
NASA's OCO-2 is the first spacecraft devoted to CO2 monitoring, which was successfully launched in July 2014 (Wunch et al. 2017). OCO-2 measures the CO2 mole fraction in column-averaged dry air with the accuracy, resolution, and coverage needed to identify CO2 sources and sinks on a regional and global scale (Crisp et al. 2004). This satellite operates in a Sun-synchronous orbit that flies at 705 km altitude with a local overpass time of 13:30 (Crisp et al. 2017). OCO-2 have a repeat cycle of 16 days and complete global XCO2 coverage twice per month, with a spatial resolution of approximately 3 km2. The validation results of OCO-2 data against high-precision measurements (ground-based or aircraft observations) indicate that precision is less than 0.5 ppm (Bi et al. 2018; Wang et al. 2021). In this research, the bias-corrected OCO-2 daily lite files (V10) from January 2015 to December 2020, with the quality flag as ‘0’ were utilized.
CubeSat project: experience gained and design methodology adopted for a low-cost Electrical Power System
Published in Automatika, 2022
Kamel Djamel Eddine Kerrouche, Abderrahmane Seddjar, Nassima Khorchef, Sidi Ahmed Bendoukha, Lina Wang, Abdelkader Aoudeche
The chosen mission orbit is a Sun Synchronous Orbit (SSO) with an altitude of 500km and an LTDN of 10.30 AM. The orbit parameters are shown in Table 1, which are obtained by calculations from the developed model based on the literature [12]. As an additional feature, those parameters have been compared with System Tool Kit (STK) results obtained in the numerical simulations. For the nanosatellite visibility analysis, the ground station is supposed to be located at Beihang University (39.9824° N, 116.3488° E). On the one hand, if there is a problem at the main ground station (Beihang University) that makes it unable to operate, backup ground stations can be used from which radio contact can be maintained. For the continuity of operations plan, commands can also be authorized from these redundant ground stations. On the other hand, other stations in the amateur radio community may be allowed to listen to, download, and decode CubeSat data. For this purpose, the frequencies and operating modes of this CubeSat can be published.
Latitudinal fluctuation in global concentration of CO2 and CH4 from shortwave infrared spectral observation by GOSAT during COVID-19
Published in International Journal of Digital Earth, 2021
Laxmi Kant Sharma, Rajani Kant Verma
Greenhouse Gas Observing Satellites (GOSAT) can monitor the greenhouse gas concentration in continuous space and time, such as CO2, CH4, O3, and water vapor. It was developed to retrieve total-column abundances of CH4 and CO2. The satellite's altitude is 666 km in a sun-synchronous orbit with 98˚ inclination that crosses the Equator at 12:49 local time. It observes column-averaged dry-air mole fraction of CH4 and CO2 with a footprint of 10.5 km2 at nadir by Thermal and Near-Infrared Sensor for carbon Observation (TANSO)-Fourier Transform Spectrometer (FTS). Another sensor, namely TANSO–Cloud and Aerosol Imager (TANSO-CAI), is used to recognize aerosol and cloud data such as effective radius, optical thickness, cloud and aerosol properties, and existence by TANSO–FTS. Band number 3 and 4 of TANSO–FTS belongs to a strong water vapor absorption band and a thermal infrared band, respectively (Eguchi and Yoshida 2019; Sharma and Verma 2020; Mustafa et al. 2020; Belikov et al. 2021).