China launches second classified Gaofen-13 remote sensing satellite

China added its initially civilian Gaofen Earth observation series Friday with the launch of the classified optical geostationary Gaofen-13 (02) satellite. A Long March 3B rocket lifted off from the hill-surrounded Xichang Satellite Launch Center at 4:33 a.m. Eastern, March 17. The launch successfully sent the Gaofen-13 (02) satellite into geosynchronous transfer orbit, the China Aerospace Science and Technology Corp. (CASC), announced. The payload was only revealed after launch, with speculation that the Long March 3B would carry a ChinaSat communications or Beidou navigation satellite. CASC provided no details of the satellite’s capabilities, stating only that the optical remote sensing satellite is a high-orbit, high-resolution Earth observation technology satellite with great significance to the development of China’s space technology. The mission patch features a galloping horse behind a Long March 3B rocket. The Gaofen-13 (02) (gaofen means high resolution) satellite is nominally part of the civilian China High-resolution Earth Observation System (CHEOS). Land surveys, crop yield estimation, environmental governance, meteorological early warning and forecasting, as well as comprehensive disaster prevention and mitigation are noted as the main uses of the satellite, according to Chinese state media. The first Gaofen-13 satellite was launched in October 2020, also using a Long March 3B rocket. The pair are thought to be more capable versions of the Gaofen-4 geostationary optical satellite launched in December 2015. Gaofen-4 has a reported ground resolution of 50 meters.

Gaofen-13 (02) heads for GTO atop of a Long March 3B lifting off from Xichang, March 17, 2023. Credit: Ourspace

China also stated earlier in the year that it planned to launch a 20-meter-resolution synthetic aperture radar satellite to geostationary orbit in 2023.

(CHEOS) was approved in 2010 and was initially planned to consist of seven Gaofen satellites and a near space and airborne system and a ground segment, according to China National Space Administration (CNSA) presentations to the United Nations Office for Outer Space Affairs (UNOOSA).

While details have been published of the Gaofen 1 through 7 satellites, those designed Gaofen-8 remain classified, indicating military customers.

China has so far launched four Gaofen-11 satellites from Taiyuan Satellite Launch Center in north China using Long March 4B rockets. Earlier reports indicate these satellites belong to the classified segment of China’s Gaofen series, with the capability to return optical imagery at a resolution of around 10 centimeters.

CHEOS comprise optical, multispectral, hyperspectral and synthetic aperture radar satellites. A CHEOS near space segment comprising airships, air flight platforms, and airborne Earth observation instruments and data processing system was however also included in the plan to augment its capabilities and data collection, though little information has been published on this aspect.

The balloon and other platforms are to carry three types of earth payloads, including optical, laser and synthetic aperture radar (SAR). These were to be capable of providing images with a spatial resolution of better than 0.1 meters, and a spectral resolution of better than 1 nanometer.

Notably this is much higher than the 1 meter spatial resolution intended to be provided by the Gaofen satellites. The balloons would also allow surveillance for longer periods of time than the few minutes it takes a satellite in LEO to pass overhead.

An undeclared Chinese high altitude surveillance balloon was detected in U.S. airspace earlier this year. Reports followed of a variety of high-altitude surveillance balloons in countries across five continents, suggesting balloons have been widely deployed for data collection.

The New York Times reported Feb. 13 that in 2019 an airship was sent around the world, including across North America. That near-space vehicle was, according to sources linked within the story, developed as part of CHEOS.