Gaofen satellite launched by Long March 4C

by Rui C. Barbosa

China launched a new remote sensing satellite on Friday, with a Long March 4C lofting Gaofen-10’s replacement.

The launch took place at 18:50 UTC from the LC9 launch complex at the Taiyuan Satellite Launch Center.

The Chinese media is referring to the new satellite as a new remote sensing bird that will be used for “land survey, urban planning, crop yield assessment, and disaster prevention, mitigation and monitoring”.

It is possible that this new satellite might be a direct replacement for the previously lost Gaofen-10 satellite. Gaofen-10 was lost on August 31, 2016 when problems developed with its launch vehicle. The exact nature of that satellite was never disclosed.

Gaofen (“High Resolution”) is a series of civilian Earth observation satellites developed and launched for the state-sponsored program China High-definition Earth Observation System (CHEOS).

In May 2010, China officially initiated the development of the CHEOS system, which is established as one of the major national science and technology projects.

The Earth Observation System and Data Center of China National Space Administration (EOSDC-CNSA) is responsible for organizing the construction of the CHEOS that is near-real-time, all-weather, global surveillance network consisting of the satellite, stratosphere airships, and aerial observation platforms.

The Earth Observation System and Data Center, China National Space Administration was established in March, 2010.

The Center is principally responsible for organizing and implementing as well as managing CHEOS. It is also responsible for EO application services, commercial development, technology consultant and international cooperation.

By following an arrangement of integral observation from space, air and ground, the CHEOS is developing a space-based system, near-space system, aerial system, ground system and application system.

This is to create Earth observation at a high temporal, spatial and spectral resolution, which is making good progress.

To meet the strategic demands of the national economic development and social progress, the initial plan involved five satellites.

Gaofen-1 employed a CAST2000 bus, configured with one 2 meter panchromatic / 8 meter multi-spectral camera and one 16m multispectral medium-resolution and wide-view camera.

The satellite integrates imaging capacity at medium and high spatial resolution and with large swath, with a designed lifespan of over five years. It was launched on April 26, 2013.

Gaofen-2 employed a CS-L3000A bus, configured with one 1 meter panchromatic/4m multi-spectral camera, with a designed lifespan of over 5 years. The satellite was launched on August 19, 2014.

Designed by CAST (China Academy of Space Technology), Gaofen-3 employs the CS-L3000B bus configured with multi-polarized C-band SAR at meter-level resolution. The satellite had a designed lifespan of eight years and will mainly be used by the State Oceanic Administration (SOA) of China. GF-3 was launched on August 9, 2016.

Gaofen-4 was developed by CAST and is based on the new GEO remote-sensing satellite bus. It has an orbital mass of 4,600 kg, and was designed for a lifespan of 8 years. The satellite was placed into orbit by a Long March-3B launch vehicle from the Xichang Satellite Launch Centre on 29 December 2015.

Gaofen-4

Gaofen-5 employs SAST5000B bus and is configured with six types of payloads, including visible and short-wave infra hyperspectral camera, spectral imager, greenhouse gas detector, atmospheric environment infrared detector at the very high spectral resolution, differential absorption spectrometer for atmospheric trace gas, and multi-angle polarization detector. It is designed for 8 years and was launched on May 8, 2018, using a Long March-4C rocket from Taiyuan.

A Long March-2D orbited the Gaofen-6 satellite out of Jiuquan on June 2, 2018. This was an optical satellite similar to the Gaofen-1, but using a different instrument suite, consisting of a 2/8 m resolution panchromatic/hyperspectral camera with an image swath of >90 km and a 16 m resolution wide-angle camera with an 800 km image swath. Both cameras use a three-mirror anastigmat telescope. Both covers visible light to NIR bands.

Gaofen-5 during testing.

On June 26, 2015, China launched the Gaofen-8 satellite. Developed by the China Aerospace Science and Technology Corporation (CASC), the satellite is part of a civilian program whose aim is to facilitate climate surveying, disaster response, precision agriculture mapping, urban planning and road network design.

Its imagery will be mostly used by the Ministry of Land and Resources, the Ministry of Environmental Protection, and the Ministry of Agriculture. The satellite was launched from the Taiyuan Satellite Launch Center using a Long March-4B rocket.

On September 14, 2015, another Gaofen satellite, Gaofen-9, was launched from the Jiuquan Satellite Launch Center, using a Long March-2D. Possibly a civilian version of the Yaogan Weixing-2 (Jianbing-6) satellite, Gaofen-9 will provide sub-meter class resolution optical images for city planning, road network design, land ownership determination purposes.

A Gaofen-1 triplet was launched on March 31, 2017, by a Long March-4C from Taiyuan.

What appears to be a high-resolution optical Earth observation satellite, Gaofen-11, was launched on July 31, 2018, using a Long March-4B launch vehicle from Taiyuan.

Related Articles