VESSEL — TECHNICAL FIELD GUIDE / ТЕХНИЧЕСКИЙ СПРАВОЧНИК
PHASEPROJECT 921
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← INDEX — FIG. 00 — 15 OCTOBER 2003, 01:00 UTC JIUQUAN · 42.4°

VESSEL
SHENZHOU AND CHINA'S CREWED PROGRAM

China became the third country to launch people into space.

BEGIN — CHAPTER 01 →
CH.01 / 10 — A PLAN IN THREE STEPS

Project 921: named after the day it was approved

Project 921 was approved on 21 September 1992.

The striking thing is persistence.

CH.02 / 10 — THREE MODULES, ONE OF THEM LEFT BEHIND

A Soyuz-like layout, built bigger

Shenzhou has three modules like Soyuz.

The orbital module stayed in orbit as a satellite.

CH.03 / 10 — ONE ASTRONAUT, FOURTEEN ORBITS

Shenzhou 5: twenty-one hours and fourteen sunrises

Yang Liwei flew 14 orbits in 21 hours 22 minutes.

Fourteen sunrises in a single day.

ECLIPSE FRACTION OF A CIRCULAR ORBIT
f = (1/π) · arccos[ √(h² + 2Rh) / ((R + h) cos β) ]  for |β| < β* = arcsin(R/(R + h)), else 0
Cylindrical shadow, spherical Earth.
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CH.04 / 10 — TWO ASTRONAUTS, THEN THREE AND A SPACEWALK

Living in the ship, then stepping outside

Shenzhou 6 flew two astronauts for almost five days.

Zhai Zhigang made China's first spacewalk in 2008.

CH.05 / 10 — CATCHING A SPACE LABORATORY

To catch up, fly lower

Shenzhou 9 made the first manual docking; Liu Yang was the first Chinese woman in space.

To catch up in orbit, go lower.

PHASING: HOW FAST A LOWER ORBIT GAINS
n = √(μ / r³)  ·  tcatch = θ0 / (nchaser − nstation)  ·  ΔvHohmann ≈ √(μ/r₁)·[√(2r₂/(r₁+r₂)) − 1] + √(μ/r₂)·[1 − √(2r₁/(r₁+r₂))]
Circular orbits.
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Station height fixed at 390 km.

CH.06 / 10 — STEP THREE: A STATION OF ITS OWN

Six-month crews and a docking in three and a half hours

Shenzhou 12 docked 6.5 hours after launch; Shenzhou 13 stayed 182 days.

Crews rotate every six months; Shenzhou 21 docked in about 3.5 hours.

CH.07 / 10 — NOVEMBER 2025: THE CRACKED WINDOW

A speck of debris, a lifeboat swap and an empty seat home

Shenzhou 20's window was cracked by suspected debris.

Shenzhou 22 launched as a replacement lifeboat.

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Energy only.

CH.08 / 10 — THE STEP THAT WAS NOT IN THE PLAN

Mengzhou, Lanyue and a Moon landing “by 2030”

China aims to land astronauts on the Moon by 2030.

Tests of Lanyue and Mengzhou are under way.

CH.09 / 10 — LEGACY: ONE PLAN, THIRTY YEARS

From approval to a permanent station

It was never the fastest programme.

CH.10 / 10 — REFERENCES

Sources cited throughout this guide