China Plans to Develop and Launch Over Ten Marine Observation Satellites of Three Series by 2020
At 6:57 AM of October 25, a HY-2B satellite was launched into the orbit at Taiyuan Satellite Launch Center (TSLC). It is the second marine observation satellite launched within more than one month after HY-1C’s successful injection on September 7.
What is a marine observation satellite? What payload can this satellite carry? What specific characteristics do HY-2B and HY-1C have? What about the current situation of China’s development in marine observation satellites? What’s its planning in the future? It is beyond doubt for people to focus on these issues.
Discerning eyes over seas from the space
A marine observation satellite, which is mainly applied in detection of ocean color, is an artificial earth satellite developed and launched specially for the development and utilization of marine biological resources, monitoring and control of marine pollution, development of coastal resources and scientific researches of seas. Zhang Qingjun, chief commander and chief designer of the HY-2B satellite, indicated that seas covering 70% of the total surface of the earth, are a cradle of life, a treasury of resources, an important regulator of global climate and also a principal passageway for world trade. The human society cannot dispense with seas to obtain a sustainable development, and in turn seas will contribute much to the prosperity and development of the human society. Therefore, an in-depth knowledge of seas is required for development, utilization and protection, and an artificial earth satellite can provide essential technical means for human kind to know the sea in a large-area, high-precision and all-dimension manner, maintaining a suitable environment for marine development, including economic prosperity. Since China is a maritime nation, it shares its responsibility in the promotion of human kind’s awareness of seas and shoulders the mission of marine ecological protection and sustainable utilization of resources and environment. Therefore, by expanding application fields and scopes of marine observation satellites and thereby establishing a satellite system, China has been aiming at developing itself into a maritime power.
According to Jiang Xingwei, director of National Satellite Ocean Application Service of Ministry of National Resources, marine observation satellites’ wide-range and long-term observation on global seas furnishes such a data source for human kind’s exhaustive knowledge of seas as that it cannot be replaced by other observation methods. A marine observation satellite detects marine environment information through its in-built remote sensors. Varying along with types of in-built remote sensors, functions of marine observation satellites can be divided into three categories specifically, i.e. ocean color satellites, marine dynamic environment satellites and sea monitoring & surveillance satellites.
Jiang also added that the United States is the first country to develop the remote sensing technology of marine observation satellites and headed the world with its first launch of SEASAT in 1978. In the past four decades, the United States have developed several types of marine observation satellites for special purposes, such as satellites for sea environment, marine dynamic environment and ocean color, attaining the ability of capturing information about ocean color and marine dynamic environment. In February 1979, the Soviet Union launched its first marine observation satellite Cosmos-1076 for test and parameter measurement of marine meteorology and atmospheric physics. After that, its fourth-generation series of marine observation satellites were also launched. With bequeathed technologies from the Soviet Union, Russia also launched its satellites for marine observation, including the Meteor-MN3. From 1991 on, the European Space Agency (ESA) successively launched ERS (Europe Remote Sensing Satellite) series followed by the Envisat. In October 2006, ESA started launching MetO series of satellites, etc. At present, nearly one hundred marine observation satellites or earth observation satellites for marine survey have been launched throughout the world.
Establishment of satellite constellation system for marine observation
Same as the HY-2A satellite launched in August 2011, the newly and successfully launched HY-2B, which is also a marine dynamic environment satellite with the monitoring and survey of marine environment as its principal mission to obtain several parameters of marine dynamic environment, such as surface wind, wave height, currents, surface temperature, directly provides measured data for warning and forecasting catastrophic sea conditions and supporting services in terms of disaster prevention and reduction, maritime rights safeguard, environmental protection and scientific researches, etc.
The HY-2B, even though newly launched, outweighs its “elder brother”, the HY-2A in two respects. The first respect is its multiple functions. In addition to the radar altimeter, microwave scatterometer and other loads, the HY-2B’s newly-installed system for ship identification and data collection is capable of automatically identifying ships everywhere in the world and receiving, storing and transmitting buoy measurement data from both coastal waters of China and other waters. The second respect lies in its nice system fusion. Since a satellite is a highly-integrated spacecraft, it is crucial to ensure a nice fusion between its internal systems. In order to ensure a smooth function without any mutual impact between loads and a more accurate observation of marine dynamic environment elements, including surface height, wind field, temperature, etc., the HY-2B research team performed targeted treatments of several links such as whole-satellite final assembly, subsystem, loads, stand-alone machines and cable enwrapping.
Being the third satellite of the HY-1 series and a type of ocean color satellite, the HY-1C is applied for observation of optical characteristics of seawater, chlorophyll concentration, surface temperature and marine pollutants while obtaining observation data related to seawater, shallow water topography, current characteristics and other elements. After the successful launch of HY-1C, the satellite not only supports its application in meteorology, agriculture, water conversation and other industries, but also provides date services in operational monitoring of global ocean color and temperature, resource environment investigation of offshore waters, islands and coastal zones, disaster prevention and reduction, sustainable utilization of marine resources, ecological warning and environmental protection. On the HY-1C, five payloads are mounted: Ocean color and temperature scanner, coastal zone imager (CZI), ultraviolet imager, spectrograph for onboard calibration and automatic identification system of ships. Compared with HY-1A and HY-1B, HY-1C has substantially enhanced performance in observation precision, scope of observation and service life. For instance, its ocean color and temperature scanner, whose scanning width is almost twice as broad as that in HY-1A, fulfills a global scanning within a single day. Since the injection of HY-1C, all its loads operate smoothly, and a large number of high-quality data have been sent back.
Gaofen 3 (GF-3) successfully launched in August 2016 is China’s first radar imaging satellite, which is also applied for sea and land observation. Besides its all-weather and all-time surveillance and monitoring of sea and land information on a global scale, the Gaofen 3 can also enlarge its range of observation and enhance its ability of quick response through attitude maneuver. According to Zhang, during the development of this satellite, Chinese scientists have surmounted several key technologies regarding to whole-satellite mechanical-electrical-thermal integration design, multi-polarization phased array antenna and high-power pulse power supply, and the overall performance of the satellite has reached international advanced level. Aside from observing the storm surge, tropical cyclone, sea ice, oil spill, green tide, etc. of adjacent waters, the Gaofen 3 can also be applied in monitoring coastal zones, artificial facilities on reefs, offshore petroleum platforms, etc., providing information supports for monitoring and assessment of disasters as well as responding to major environmental accidents. The operational utilization of Gaofen 3 has significantly improved domestic situation of absolute dependence on import of high-resolution images through civil space-based synthetic-aperture radars (SAR), and it weighs much technologically in marine development, monitoring of land environmental resources and disaster prevention and reduction by providing domestic users of all industries with high-quality and high-precision earth observation data.
Valuable data resources to serve the world
At present, a series of satellites for ocean color, marine dynamic environment as well as surveillance and monitoring have taken initial shape, which are represented respectively by the HY-1, HY-2 and GF-3, and an observation system of remote sensing satellites that complement each other’s advantages has been established to generate social and economic benefits.
Considering its strategy of building a maritime power and demands in respects of marine resource development, environmental protection, utilization and administration of sea areas, management of polar oceans as well as maintenance of marine rights and interests, etc., China should focus on the development of a series of sea satellites to provide comprehensive information services in monitoring of marine catastrophes and disaster prevention and reduction, establishing a system of three types of marine observation satellites to build China’s own marine observation satellite constellation, Zhang added.
According to a medium-and long-term development program of China’s civil space infrastructure and “The 13th Five-year Plan for the Development of Marine Observation Satellite Business”, China will develop and launch over ten satellites of the above-mentioned three types by 2020, Jiang Xingwei said. To be specific, in terms of ocean color satellites, HY-1C hopefully embrace its younger brother of HY-1D in 2019 to constitute China’s first sea satellite constellation for civil purposes, which will greatly enhance the ability of worldwide coverage through network observation. As for ocean dynamic satellites, HY-2B will greet in succession its followers, i.e. HY-2C and HY-2D, to create a network of three satellites for detection of the height, wind field and temperature of sea surface. Additionally, CFOSAT and salinity detection satellites will be launched as a new type of ocean dynamics satellite to detect ocean wave spectra and salinity information. In terms of marine surveillance and monitoring, the GF-3 will join hands with two future operational satellites mounted with synthetic-aperture radars (SAR) to form a network for such purposes.
The simultaneous on-orbit operation of these three series of satellites provides several fields, such as marine environmental resources, disaster prevention and reduction, economy, ecology and safety, with resourceful multi-source marine environmental information of different resolution, time effect and varieties while meeting some business requirements in industries of meteorology, environment, transportation, agriculture and water conversation, etc.
It is noteworthy that the marine observation satellite constellation system to be established with all efforts is an integral part of the international space infrastructure. Therefore, relevant data obtained through this system in the service of itself are also open to all nations and areas to benefit the international community, including the United States and many other countries.
In October 2012, the HY-2A contributed much in America’s fighting against Hurricane Sandy, Zhang Youguang said, who was a researcher from National Satellite Ocean Application Service of the Ministry of Natural Resources and also chief designer of HY-2 ground application system. The HY-2A observed Sandy one day before its breakout and predicted its accurate direction of movement, which was essential in the time race with the hurricane for effective precautions. A researcher from National Oceanic and Atmospheric Administration (NOAA) pointed out after analysis that, HY-2A, which was the only satellite in the world that could capture on-orbit sea height information during a hurricane, had provided valuable data sources in observation of the Hurricane Sandy.