The Chang'e-5 lunar sample return mission is pretty complicated. The spacecraft has a lot of sub-pieces and the mission has a lot of phases. I am going to take a deep breath and summarize what I believe the scenario to be.
First, the Lego pieces (abbreviations are mine):
SM: Service module
DS: Descent stage (lander)
AS: Ascent stage
AD: Adapter
DA: Docking adapter
RV: Reentry vehicle
At launch, the stack has the AS on top of the DS on top of the AD on top of the SM, wit the DA on top of the RV sitting on the SM inside the AD.
The phases: 1) Possibly, phasing Earth orbits prior to translunar injection (awaiting clarification). 2) Translunar injection and coast 3) Lunar orbit insertion, maybe to elliptical orbit. 4) Lunar orbit manuevers to low circular lunar orbit.
(continued)..
5) DS+AS separate from SM+AD, in lunar orbit. 6) AD is ejected from SM, revealing DA+RV attached to SM. AD remains in lunar orbit. 7) DS+AS land on Moon and obtain sample, placed in AS 8) AS takes off, leaving DS on moon.
(continued)
9) AS enters lunar orbit and makes rendezvous burns 10) AS docks with the DA on the SM 11) DA mechanism transfers sample from AS to RV 12) AS+DA ejected from the SM+RV. AS+DA remain in lunar orbit.
(continued)
13) SM+RV move to elliptical lunar orbit. 14) SM makes trans-earth insertion burn 15) SM+RV trans-earth coast. 16) RV separates from SM
(continued)
17) SM *either* burns up on Earth atmo entry *or* performs avoidance burn to begin new extended mission. 18) RV hypervelocity atmo entry, jettison aeroshell, deploy parachute, lands in China (Inner Mongolia province).
(continued)
19) The AS+DA, and separately the AD, remain in low lunar orbit until mascons perturb them to impact the lunar surface (probably of order 1 year?)
Next challenge: what is the breakdown of the wet and dry masses of each of these components, totalling 8200 kg at launch? I solicit estimates.
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Chang'e-5 will launch aboard the Chang Zheng (Long March) 5 serial number Y5 from pad 101 at the Wenchang space centre on Hainan island. The CZ-5 rocket has 4 liquid side boosters, core stage, and upper stage. The upper stage will go to parking orbit and then translunar insertion
The CE-5 will separate from the CZ-5 second stage on its translunar trajectory, and coast on to lunar orbit insertion in a few days.
After some time in lunar orbit, the lander will separate from the service module and touch down. The lander ascent stage will then take off with its sample and dock with the service module in lunar orbit, transferring its samples.
The predicted close approach on Oct 16 involves a Soviet Parus navigation satellite and a Chinese rocket stage. Here is the Parus. It's a big satellite, about 800 kg, 2 metres in dia and it has a 17 metre long gravity gradient boom.
The Parus satellite was designed by ISS Reshetnev in Zheleznogorzk and built by PO Polyot in Omsk. Images from kik-sssr.ru
The CZ-4C third stage is about 7.5m long and 2.9m diameter. I don't have a good mass for it but it is probably of order a tonne. Here is art of the stage from the specific launch in question with the payload still attached at right
A TsSKB-Progress Soyuz-2-1a rocket stands on the pad at Baykonur's Area 31, ready to launch an RKK Energiya Soyuz-MS spaceship.(Confusingly 'Soyuz' can refer to either the rocket or the spaceship on top.)
The Soyuz 2-1a rocket has taken over human spaceflight launch duties from the now-retired Soyuz-FG rocket. Today's rocket is serial Kh 15000-045 and is the 41st Soyuz-2-1a to be launched.
There is a further upgraded version, the Soyuz-2-1b, with a newer third stage engine - apparently they don't trust this for piloted missions. The Soyuz-2-1a and 2-1b use a lower stage design derived from the original 1957 R-7 ICBM and 8K71PS Sputnik launch vehicle.
Here are all the actual satellites in orbit in this range of heights and inclinations (green = working, red = dead). See how they are almost all right on the magenta SSO line. They are also almost all below 1000 km. The rest of the diagram is really empty of satellites!
Now let's add in orbital debris. Generic orbital debris in black; debris from the 2007 Chinese antisatellite test in blue. You couldn't have picked a much worse region of orbital parameter space to make a big debris cloud.
Finally, here is a zoom in on the busiest part of SSO, omitting the debris
A nice cache of declassified documents on the Soviet E-8 lunar program has been released to commemorate the anniversary of Luna-16: roscosmos.ru/29219/
One thing I hadn't registered before is that Lunokhod is referred to as L-2, in the sequence between L-1 (Zond) and L-3 (human landing missions). I guess @historyasif already knew this though.
@historyasif The documents also include official contemporary reports noting the payload fairing failure on the first Lunokhod launch (Feb 69) and the Blok-D ignition failure on the first E-8-5 sample return attempt (Jun 69).
The debris object that ISS avoided is now available on SpaceTrack as 2018-084CQ, 46477, from the breakup of Japan's H-2A F40 rocket stage. At 2221:07 UTC it passed within a few km of ISS at a relative velocity of 14 6 km/s, 422 km over the Pitcairn Is in the S Pacific
Correction: it passed within a few km of the position ISS would have been at if it hadn't manuevered
H2A F40 launched GOSAT-2 in Oct 2018. The stage appears to have made a depletion burn to lower orbit from 597 x 618 km to 598 x 520 km. Nevertheless it underwent a major breakup on 2019 Feb 6.