China's Space Program News Thread

[by78]

 

[SanWenYu]

transmission rate is up to 2.5Gbps at a distance of 5000m

Is this a typo? The PPT says 2.5Gpbs @ 3000km which makes sense for "inter-satellite" communication.

 

[escobar]

View attachment 89287

The reusable experimental spacecraft launched in sep 2020?

 

[by78]

Is this a typo? The PPT says 2.5Gpbs @ 3000km which makes sense for "inter-satellite" communication.

Sorry, that was a typo.

 

[siegecrossbow]

The reusable experimental spacecraft launched in sep 2020?

I have no idea. It is possible.

 

[taxiya]

Do you have data on shenzhou and crewdragon landing accuracy? Can only imagine China's next gen spacecraft would be even better than shenzhou.

Since they've tested the next gen spacecraft twice already, is there data on that? In any case Landers on other planets would be different again. The Chinese one certainly did that better.

I made the comparison in this forum some time ago. If you remember seeing this picture.



The data source of Shenzhou is the CCTV broadcast of Shenzhou 12 reentry. It can be found here

The first prediction of landing point is 100 04 46E 41 37 23N. The real landing point is 100 04 26E 41 37 46N. The offset is 840 meters.

The first prediction is made just after the retro engine is shut but before the reentry vehicle and service module separation. From this moment, they are basically free flying. The final accuracy is determined by how well active control works before this point. After this point nothing much can be done to affect the accuracy.

For SpaceX, I took this recording from NASA.

In my earlier post I asked confirmation about the definition of "RNG" (range) from other members but got no answer. Anyway, I believe it means Range from the predicted landing point. I watched this number decreasing from 749067NM to 4.5NM. At 4.5NM dragon was 300 meter above water. So I concluded that 4.5NM is the offset to the predicted landing point. 4.5NM is 8.3km. From the looks of the video, there is not much wind, so the final point would not be much better, let's say 7 to 8 km.

The difference is 840 meters vs. >7000 meters. To me, that is huge.

 

[taxiya]

Seems like a huge leap in logic.

Not if you actually compare the landing accuracy of Shenzhou 12 and crew dragon.

 

[SunlitZelkova]

View attachment 89287

This is probably a falling booster from a Long March 3B that has been photoshopped with exhaust. I remember a similar image from around April Fool's.

 

[by78]

The Mars orbiter's high-resolution camera. Sorry, but translating the technical slides is beyond me, but here's what I can make out: The camera weighs 43kg, the primary mirror aperture is 387mm, the focal length is 4640mm, a field of view is 2º, etc.

The medium-resolution (中分辨率相机) and high-resolution (高分辨率相机) cameras on the Tianwen-1 Mars orbiter.

 

[by78]

An old photo showing China's first batch of taikonauts taking oath of induction into the taikonaut corps.