Blue Marble image of the Earth taken by the crew of Apollo 17 on Dec. 7 1972.
Image Credit: NASA

Earth observation making lead international headlines around the world isn’t a common occurrence. So, after talking about high altitude pseudo satellites (HAPS) a couple of times in the last few weeks, there is really only one place to start this week; the Chinese high altitude surveillance balloon that the US military shot down earlier this week.

Earth Observation Balloons

Visually the Chinese balloon looked more like a stratospheric weather balloon than a HAPS, these are the types of balloons that are regularly launched – even Pixalytics was involved in such a launched five years ago in conjunction with the Plymouth University Space Society. To a degree it doesn’t matter if it is a weather balloon or a HAPS as both can carry payloads, and can be used to collect either weather data or to spy – our balloon had a GoPro camera on it to take images. China has said that this was a weather balloon collecting meteorological data on behalf of a commercial Chinese company, and certainly these types of balloons tend to drift in the winds without independent propulsion. US officials have rejected this description as they have stated the balloon had propellers, which enabled manoeuvring ability. What data it was collecting and how much independent propulsion will only be known if the balloon remnants and payload is recovered from the sea, which the US Military is searching for.

On Monday, a second balloon has been acknowledged by China, which floated across Latin America. Again, it was reported as something that had blown off course due to atmospheric conditions although this was noted as being for civilian use.

It is interesting to see how EO has jumped to the top of the news agenda, and there are bound to be a few more twists in this story over the coming week.

China Earth Observation Ground Station

Perhaps the more interesting story involving China, and EO this was week, had nothing to do with balloons. China has announced that they are going to build a new ground station in Antarctica to serve China’s National Satellite Ocean Application Service (NSOAS). This is the main public body responsible for marine satellite data in China, including the development of new satellites together with the use of the marine satellite data. China has launched nine Earth Observation (EO) satellites with a focus on the ocean, and it is anticipated that this ground station will be downloading and collating the data from these satellites.

These include the two series of HaiYang (HY) satellites with various optical and radar instruments with the aim of monitoring and investigating ocean environment, getting ocean dynamic and environmental parameters, including sea surface wind, sea wave height, ocean current, sea surface temperature, etc.

• HaiYang-1 series of sun-synchronous satellites carry a ten band optical China Ocean Colour & Temperature Scanner (COCTS), 4 band Coastal Zone Imager (CZI), and an ultra violet imager. These are:
  • HaiYang-1C (HY-1C) launched in September 2018
  • HaiYang-1D (HY-1D) launched in June 2020.
  • Two earlier satellites in the series, HaiYang-1A (HY-1A) and HaiYang-1B (HY-1B) had been active, but reached end of life in April 2007 and February 2016 respectively.
  • HaiYang-1E (HY-1E) is expected to be launched later this year.
• HaiYang-2 series sun-synchronous satellites are listed below, with 2A and 2B carrying a dual frequency altimeter, scatterometer and microwave imager, whilst 2C and 2D don’t carry the microwave imager.
  • HaiYang-2A (HY-2A) launched in August 2011.
  • HaiYang-2B (HY-2B) launched in October 2018
  • HaiYang-2C (HY-2C) launched in September 2020.
  • HaiYang-2D (HY-2D) launched in May 2021

In addition, the capabilities include the Chinese-French Oceanography Satellite (CFOSAT) which carries the CFOSAT scatterometer and the Surface Waves Investigation and Monitoring instrument.

The new station will be built by China Aerospace Science and Industry Corporation, at the Zhongshan research base in East Antarctica at a reported cost of $6.53 million. China has been following an approach of developing its own extensive ground station network for many years, particularly after 2020 when its contracts with Sweden Space Corporation to have access to ground stations in Australia, Chile and Sweden were not reviewed due to changes in the political situation.

With the region only supposed to be used for peaceful purposes according to Antarctic Treaty which China, United States and the UK have signed along with approximately 50 other countries, it will be interesting to see if China continues to develop its presence in the area. If it does, there will be another international debate surrounding EO and these flashpoints are likely to increase in coming years.