After being linked for almost six months, China’s Shijian 21 and Shijian 25 separate
After rendezvousing and doing repeated docking tests in June and July and then remaining linked since then, China’s Shijian 21 and Shijian 25 test satellites have now separated.
Optical ground observations Nov. 29 made by S2a systems, a Swiss company which develops and operates customized systems for optical space surveillance worldwide, reveal that the two satellites have now separated in geosynchronous orbit, close to the geostationary belt (GEO) at 35,786 km above Earth’s equator. The orbits of the pair are inclined by 4.6 degrees with respect to GEO.
The article at the link speculates that the spacecraft were doing refueling tests while docked, but while a good guess this has not been confirmed anywhere. China has said nothing.
Shijian-21 was launched in 2021, and was used to grab a defunct Chinese geosynchronous satellite and tug it to a graveyard orbit. Shijian-25 was launched in January 2025, apparently intended to test robotic servicing of satellites. These maneuvers with Shijian-21 appear to be part of those tests. Whether those tests included refueling is uncertain, though possible. If Shijian-21 proceeds to do additional satellite tug maneuvers then it will strongly suggest this refueling occurred and was successful.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
After rendezvousing and doing repeated docking tests in June and July and then remaining linked since then, China’s Shijian 21 and Shijian 25 test satellites have now separated.
Optical ground observations Nov. 29 made by S2a systems, a Swiss company which develops and operates customized systems for optical space surveillance worldwide, reveal that the two satellites have now separated in geosynchronous orbit, close to the geostationary belt (GEO) at 35,786 km above Earth’s equator. The orbits of the pair are inclined by 4.6 degrees with respect to GEO.
The article at the link speculates that the spacecraft were doing refueling tests while docked, but while a good guess this has not been confirmed anywhere. China has said nothing.
Shijian-21 was launched in 2021, and was used to grab a defunct Chinese geosynchronous satellite and tug it to a graveyard orbit. Shijian-25 was launched in January 2025, apparently intended to test robotic servicing of satellites. These maneuvers with Shijian-21 appear to be part of those tests. Whether those tests included refueling is uncertain, though possible. If Shijian-21 proceeds to do additional satellite tug maneuvers then it will strongly suggest this refueling occurred and was successful.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

