23 Jun 2022: In its second launch of the week, China launched its second batch of Yaogan-35 satellites from the Xichang Satellite Launch Center aboard a Chang Zheng 2D. The satellites, called Yaogan 35 Group 2, are possibly related to another triplet of payloads that launched in November 2021 from the same spaceport on the same rocket. Launch Video.
– China reported the satellites would be used for “scientific experiments, land and resource census, and other fields;” however, that generic statement was to not give away the true purpose of the vehicles.
– No details on equipment, mass, or specifics were made public. Based on past missions, they were likely built by DFH Satellite based in Beijing or by the Shanghai Academy of Spaceflight Technology (SAST).
– Yaogan-35 D/E/F satellites are in a similar orbit to their predecessors, in a near circular orbit with an apogee of 503km and perigee at ~489km (e=.002). Both sets of satellites are inclined 35°.
– Other Yaogan satellites that deploy in triplets are the Yaogan-30 (30 satellites) and Yaogan-31 (12 satellites). Yaogan-30 satellites are believed to be SIGINT satellites and are also in 35 degree inclined orbits.
– Yaogan-30 satellites orbit at ~100km higher altitude and are equally spaced over the earth (separated by 120 degrees). Yaogan-31 satellites are also launched in triplets, operate in low earth orbit and within close proximity of one another.
– Yaogan-35 is at a different inclination than Yaogan-31 satellites and less than half their altitude. All Yaogan-31 satellites are inclined at 65 degrees and ~1100km altitude.
– All other Yaogan satellites operating at ~500km altitude are believed to be imagery satellites and are in sun-synchronous orbits (inclined at ~98 degrees).
– Yaogan-35 satellites may operate in lead-trail configuration, with the lead satellite potentially cueing the two trailing vehicles. The separation between the Yaogan-35 A/B/C set differs from the current Yaogan-35 D/E/F formation.
– Yaogan-35B is 4 minutes ahead of Yaogan-35A which is 1 minute ahead of Yaogan-35C. Yaogan-35E is only 1 minute ahead of Yaogan-35D which proceeds Yaogan-35F by <1 minute. The time differences are likely to change over time.
Yaogan-35 Group 2 mission patch.
Yaogan-35 Orbits.
Yaogan 30, 31 & 35 constellations - 48 combined satellites.
Yaogan-35 D/E/F formation.
Yaogan-35 A/B/C formation.
