Artist’s rendition of satellites orbiting the Earth – rottenman/123RF Stock Photo

As we approach the end of 2022, the Earth Observation (EO) industry continues to launch new satellites. This week we’re looking at the world’s two EO powerhouses, China and the United States, and the latest launches from these countries.

China

Last week, 8^th December, China launched the Gaofen 5 (01A) EO hyperspectral imaging satellite from the Taiyuan Satellite Launch Center. This is the third of the Gaofen 5 series to be launched, as Gaofen 5 was put into orbit in May 2018, and then September 2021 saw Gaofen 5-02 put into space. The satellite was developed by the Eighth Academy of China Aerospace Science and Technology Corporation and it will join the existing China High-resolution Earth Observation System (CHEOS) with a sun-synchronous orbit of 705 km.

It is reported that the Gaofen5 satellites will deliver daily global coverage and has six instruments including a visible and short-wave infra hyper-spectral camera, spectral imager, greenhouse gas detector, atmospheric environment infrared detector at very high spectral resolution, differential absorption spectrometer for atmospheric trace gas, and multi-angle polarisation detector. It’s believed that applications for the data will include ecological environment dynamic monitoring, natural resource investigation, and atmospheric composition detection, that will improve global air pollutant monitoring capabilities.

The following day, 9^th December, 14 EO satellites were put into orbit from a barge in the Yellow Sea. Eight of these were Jilin-1 Goafen 3D high resolution optical satellites developed by the commercial firm Chang Guang Satellite Technology Co. The satellites were put into a 500 km sun-synchronous orbit, and the other satellites were:

• Jilin-1 Pingtai 01A01 –  a new satellite platform adaptable to remote sensing, communications or navigation requirements.
• Golden Bauhinia-1 05 and 06– these are EO optical remote sensing satellites equipped with an optical camera and offer high-speed data transmission. The data is expected to be used for applications such as agricultural monitoring, environmental protection, transportation, and smart cities.
• Head-2H – Commercial satellites by HEAD Aerospace, for their Skywalker constellation, to track ships receiving their AIS (Automated Identification System) signals.
• Tianqi-07 – Latest in the series of experimental LEO satellites operated by Guodian Gaoke for Internet of Things communications, and they also carry a camera for educational purposes. The constellation is planned to reach 38 satellites.
• Torch-1 – China’s first commercial life science experimental satellite. Developed by private firm, Rocket Pi, it will carry out observations on microbial growth in microgravity conditions for the food industry.
• Fengtai Shaonian-2 (CAS-5A) – a nanosatellite for amateur radio communication and education.

United States Satellites

Moving across the globe to the United States, NASA has scheduled the launch of the Surface Water and Ocean Topography (SWOT) mission for this Friday 16th December, (it was scheduled Thursday 15^th December, but this launch got delayed) from the Vandenberg Space Force Base in California. This EO mission is a collaboration between NASA and the French space agency Centre National d’Etudes Spatiales (CNES) with contributions from the Canadian Space Agency and the UK Space Agency.

It is a Synthetic Aperture Radar (SAR) altimetry mission, following on from the Jason-1, -2 and -3 missions, and will be put in space via a SpaceX Falcon 9 rocket. It will eventually be in to a non-sun-synchronous orbit, at an altitude of an 891 km, to minimise tidal aliasing and cover the major terrestrial water bodies. This orbit will offer a 21 day temporal repeat cycle, but it will operate with a 120 km swath which will result in more frequent data collection across the planet with the average revisit time being 11 days.

The satellite will carry three main instruments:

• Ka-band Radar Interferometer (KaRIn): a Ka-band SAR instrument which will measure the height of water in Earth’s lakes, rivers, reservoirs, and the ocean.
• Poseidon-3C: an altimeter operating in C and Ku bands, to measure real-time high precision sea surface topography, ocean circulation and wave height data.
• Advanced Microwave Radiometer (AMR-S): a microwave radiometer to measure total water vapour along the altimeter path.

The mission aims to survey, for first time, at least ninety percent of the water on the Earth’s surface including oceans, rivers and lakes. The mission will have ten times greater resolution than current ocean observation methods, and will collect data from lakes larger than 60,000 square metres together with any river wider than 100 metres. This will help scientists track the water cycles, both for fresh and salt water, by generating a global inventory of water resources, and will help us understand how these cycles include the environment, weather and climate change.

Rest of the World

Whilst the two EO powerhouses are launching satellites, there are lots of others coming to this Christmas party, such as:

• 13th December: Meteosat-12 launched yesterday – This is the first of Meteosat’s third generation satellites and has two instruments onboard:
  • Flexible Combined Imager has 16 spectral bands and operates at a spatial resolution of between 1 and 2 km.
  • Lightning Imager will continuously monitor 80% of the planet for lightning, allowing storms to be detected earlier
• 21st December: Pleiades Neo 5 and 6 due to launch – These are the final two satellites to complete the Airbus Pleiades Neo constellation. These satellites offer spatial resolutions of 30 cm in panchromatic mode, and 1.2 m in the six band multispectral mode. (Update – sadly these two satellites were lost during launch as the Vega-C rocket that was taking them into space, crashed into the ocean shortly after take-off.)

Summary

The year is ending but in this industry that is not a time to slow down. There are still launches to happen and new data to collect!