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Launches and Orbital Operations

Tyneside, UK
2024 May 20
Monday, Day 141

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China Intrigue - 2021-076


Launch News

The 2021-076 Launch of 2021 August 24 included two satellites that went by the name 'Internet Connectivity Satellite', or some other similar name depending on translation from Chinese. There was contradiction between formal Chinese news sources with some seeming to say that there were actually three satellites, using a phrase that translates to English as "three stars, one arrow". Even Xinhua, the state news agency seemed confused, using the "three stars..." phrase in its first announcement but then saying "two satelltes" in its English language version.


The mission used a CZ 2C rocket with an added third stage. Launch used all three stages to place the stack into orbit with perigee below 200 kilometres and apogee at about 1100 kilometres. The second stage re-entered over the Indian Ocean near 36° south latitude.

The third stage (designated YZ-1S) fired again about 60 minutes after lift-off in order to circularise the orbit.

Objects in Orbit

After releasing its satellites, the YZ-1S fired a third time and precipitated its own re-entry.

Space-Track subsequently catalogued three objects in orbit - for complete details, see the zarya.info 2021 launch listing. Only one previous launch had used the YZ-1S and it too resulted in three items in orbit - two satellites and an item of debris.

With no help from China, detailed identification of the objects is very uncertain. On the face of it 076A and 076C are probably the communications satellites. The activity described in section below, singles out 076B as being different from from the others, leading to a possible conclusion that 076B is the enigmatic third object.

Orbit Activity

The three items initially pursued similar orbits as shown in the plot at the top of the page. Then, about 60 hours after launch, one of them (49113/2021-076B) started to display different behaviour. Its orbit altitude began to decrease rapidly.

2021-076B Apsides

In the next three days, both perigee and apogee decreased in unison by more than 40 kilometres. Then it settled at 19 kilometres per day.

Sep 6 - descent rate was 10 kilometres per day.

Sep 14 - the steady decrease in height ceased with the orbit at 865 kilometres.

Possible Explanations

The decrease in height has been constant so whatever force is the cause, it seems to be continuous around the orbit as indicated by matching effects on perigee and apogee.

Two possibilities spring immediately to mind:
     1 - continuous use of a thruster,
     2 - deployment of a drag device.

At the moment, it is open to debate or clarification but it does point to 076B being an instrumented object accompanying the two named satellites.

Page Date - 2021 Aug 30
Plots updated in real-time

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