Zi Yuan 3

During the early 1990s Chinese spacecraft designers were investigating the potential of a constellation of several low-mass, LEO Zi Yuan (Earth Resources) spacecraft to fulfill remote sensing objectives. One concept envisioned seven coplanar spacecraft of less than 250 kg each in a 770-km, sun-synchronous orbit. Each spacecraft would carry 4-channel CCD sensors capable of 400-km swath widths and 100-m ground resolution. Total payload mass (camera system, converters, power supply, etc.) is budgeted for only 10 kg. A cooled, multi-channel infrared camera system with a mass of 40-50 kg is also being considered but may require separate spacecraft platforms (Reference 633).

High Definition Survey Satellite ZY-3 Planned For 2011

In November 2002, the governments of China and Brazil decided to expand the initial agreement by including another two satellites CBERS-3 and CBERS-4, as the second generation of the Sino-Brazilian cooperation effort.

This new high definition civil high definition satellite may in fact be a next generation (CBERS-3) Zi Yuan 3 class spacecraft. It was said to be planned for launch in 2011 from the Shanxi Province, Taiyuan Satellite Launch Center launch infrastructure on a Long March-3B booster. It was to operate in a sun-synchronous orbit at about 506 kilometers at an inclination of 84 degrees north or south of the equator. It may serve a duel purpose Earth Resources and a “National Defense Sector” purpose as a RECSAT capability since it is a high definition system being fielded. CBERS-3 was lost in a launch mishap in December 2013.

On 08 December 2014 China successfully launched a multi-purpose satellite for monitoring, planning and management of land, forestry and agriculture. The CBERS-4 satellite was developed jointly with Brazil. It was launched from Taiyuan base using a Long March-4B rocket. It was the 200th flight for the Long March rocket family. The rocket blasted off at 11:26 am (local time) and lifted the earth resource satellite into its scheduled orbit.

CBERS-4 is one of the satellites of the Chinese-Brazilian Earth Resource Satellite (CBERS) program which began in 1988. Such satellites are used in monitoring, planning and management of land, forestry, water conservation, environmental protection and agriculture.

The China-Brazil Earth Resource Satellite-4A was launched on a Long March-4B rocket in the northern Chinese province of Shanxi 20 December 2019. The satellite was the sixth developed under the China-Brazil Earth Resources Satellite (CBERS) program that began in 1988. The satellites are designed for Earth observation from orbit for non-military use. The CBERS-4A will support the Brazilian government’s monitoring of the Amazon rainforest and changes in the country’s environment.

In a congratulatory letter sent to Brazilian President Jair Bolsonaro, Xi said that the CBERS program, initiated by China and Brazil 31 years ago, sets a good example for high-technology and space cooperation among developing countries. He expressed the hope that the two nations could continue to push forward the research and development of new satellites to enrich the content of the bilateral strategic partnership and bring more benefits to the two peoples. Brazilian President Jair Bolsonaro, in his congratulatory letter, also spoke highly of the space cooperation between China and Brazil. He said the new satellite will play an important role in the monitoring and utilization of natural resources of both countries.

Developed by the China Academy of Space Technology and Brazil’s National Institute for Space Research, the CBERS-4A carries three optical apparatus – a Chinese panchromatic, multispectral imager and Brazil’s multispectral camera, as well as a wide-field imager. It is tasked with producing remote sensing data to serve a wide range of public services in the two countries, including land resources survey, environmental inspection, climate change research, disaster prevention and agricultural forecast, according to the China National Space Administration. The administration noted that the satellite will help Brazil improve its environmental monitoring of the Amazon Region and other places. Once the satellite starts formal operation, it will gradually replace the CBERS-4, which was launched by a Long March-4B from the Taiyuan center in December 2014 and has been working since then.