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This tweet shows the image below, and says:

Finally, some images from Queqiao, the relay satellite for the Chang'e-4 far side mission, showing the Earth and Moon! Queqiao is in a halo orbit at a Lagrange point 65,000-80,000 beyond the Moon to relay comms between Earth & CE-4 on the far side (H/T @LaunchStuff).

Question: What spacecraft components are in the foreground of this image of the Earth and Moon? What is the camera inside of?

I'm looking for an understanding of this configuration in some detail, so please don't just answer "these are parts of Queqiao". Thanks!


enter image description here

A much clearer view, is this from a different camera, or different distance? Where is all of the background clutter now?

enter image description here

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  • $\begingroup$ Some searching found this tweet which might answer this question but it's way too confusing for me. $\endgroup$
    – uhoh
    Jan 10, 2019 at 2:32
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    $\begingroup$ Haven't found a Queqiao diagram yet. Some explanation of NCLE: planetary.org/blogs/guest-blogs/2018/… $\endgroup$
    – Hobbes
    Jan 10, 2019 at 8:26
  • $\begingroup$ @Hobbes it may involve those two cubesats that came along for a ride (Longjiang-1 and 2). I'm not sure but I think they went into a proper lunar orbit rather than a halo orbit like Queqiao. $\endgroup$
    – uhoh
    Jan 10, 2019 at 8:43

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Queqiao carries two cameras:

According to this Xinhua report (Chinese) following the launch, Queqiao, "carries two cameras, one large and one small. The small one will observe how the satellite antenna opens, and the large one can take group photos of the Moon and the Earth."

Annotated version of your first photo:

enter image description here

So this photo is from the engineering camera. The light-colored structure at the top is probably the antenna. That means the camera looks along the outside of the stowed antenna. This places the camera somewhere near the base of the antenna, but I can't figure out where exactly.

The box at bottom right is annotated NCLE, but it doesn't seem to match what I've been able to find about NCLE: the NCLE antennas are not on the same face as the parabolic antenna.

I've annotated this diagram to show the NCLE antennas. You can also see the curved shape of the spars that support the dish antenna.

enter image description here

The Longjiang-2 satellite also carries a camera:

One of the two Longjiang ('dragon river') microsatellites that launched with Queqiao but set to operate together in lunar orbit, carries an optical microcamera (Arabic) developed by the King Abdulaziz City for Science and Technology (KACST) of Saudi Arabia.

The instrument weighs around 630 g and is capable providing images of the Moon with a resolution of 38 m per pixel at a perilune of 300 km away the lunar surface.

And there's a second camera, for use by amateur astronomers:

Longjiang-2 carries a camera developed by KACST of Saudi Arabia, accounting for the final of four internationally-provided payloads for Chang’e-4, which sent back these cool images of the Earth and Moon.

Another onboard imager developed by students at the Harbin Institute of Technology (HIT) in northeast China has allowed radio operators to download images. Here is one such image, of Mare Nubium on the near side of the Moon.

One photo made by Longjiang-2:

enter image description here

I don't think this one took the Moon&Earth photo from the question, it orbits too close to the Moon to get that shot.

(work in progress)

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  • $\begingroup$ All around the edge of the photo there is a wall, as if the photo is taken from inside a hole. On the left there's the annotation "Spacecraft body" but something seems to go all the way around the edge. Any thoughts on that? $\endgroup$
    – uhoh
    Jan 10, 2019 at 16:31
  • $\begingroup$ no, I've no idea what that can be. There don't seem to be matching features on the diagram. $\endgroup$
    – Hobbes
    Jan 10, 2019 at 20:47
  • $\begingroup$ After about 07:00 in this video there are some Chang'e-4 graphics. I don't know if there is anything useful here, but since you've been looking at this for a while now you might find some additional info. youtu.be/Vg9GBSHfESk $\endgroup$
    – uhoh
    Jan 11, 2019 at 13:30
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    $\begingroup$ Nice find. It contains mostly higher-res versions of images I've seen before, though. I added my best guess for camera placement to my answer. $\endgroup$
    – Hobbes
    Jan 11, 2019 at 14:45

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