Featured image credit: CMSA
|October 26, 2023 — 03:14:02 UTC | 11:14:02 BJT|
|Shenzhou 17 (SZ-17)|
|China Aerospace Science and Technology Corporation (CASC)|
|China Manned Space Agency (CMSA)|
|Long March 2F/G Y17|
|Site 901, SLS-1, Jiuquan Satellite Launch Center (JSLC), in Inner Mongolia, China|
|About 8,100 kg (~17,900 lb)|
Where did the spacecraft go?
|To the front port on the Tianhe module, core of the China Space Station (CSS), or Tiangong, orbiting at an altitude of 390 km (~240 mi) and an inclination of 41.5 degrees|
Did they attempt to recover the first stage?
|No, this is not a capability of the Long March 2F|
Where did the first stage land?
|Both side boosters and first stage crashed into inland China|
Did they attempt to recover the fairings?
|No, this is not a capability of the Long March 2F|
Were these fairings new?
This was the:
|– 17th Shenzhou flight overall|
– 12th crewed Shenzhou flight
– 6th Shenzhou flight to Tiangong
– 2nd Shenzhou flight of 2023
– 493rd Long March launch overall
– 21st Long March 2F launch overall
– 2nd Long March 2F launch of 2023
– 172nd orbital launch attempt of 2023
Where to watch
What’s All This Mean?
Mission Shenzhou 17 lifts off aboard a Long March 2F (CZ-2F) rocket provided by CASC for CMSA. Jiuquan Satellite Launch Center’s Site 901, also known as South Launch Site 1 (SLS-1), is the starting point for this flight. After completing their task, the spent stages, as well as the fairing halves, fall onto inland China. Subsequently, the spacecraft separates from the second stage, starting its own journey.
Afterward, the Shenzhou spacecraft raises its orbit in search of the China Space Station, Tiangong. In effect, the plan is for the capsule to rendezvous and dock with the front port of the Tianhe core module 6:30 hours after liftoff. Later, the crew enters the station, meeting the taikonauts from Shenzhou 16, with whom they will live for some days.
Regarding the planned duration of the SZ-17 mission, the stay extends for five to six months of activity. That is, the crew should perform experiments, spacewalks, maintenance, among other tasks. Once their time in Tiangong comes to an end, they board the spacecraft and return to Earth.
How Did It Go?
CASC’s rocket lifted off at exactly 03:14:02.491 UTC, according to Chinese authorities. It is worth mentioning that, prior to launch, they only shared the boosters and first stage engines’ ignition time: 03:13:59 UTC. Following liftoff, the mission achieved these milestones:
- Maximum Aerodynamic pressure (Max Q),
- Escape tower jettisoning,
- Side boosters and first stage engines cut off,
- Side boosters separation,
- First stage separation,
- Fairing halves jettisoning,
- Second stage main engine cut off,
- Second stage vernier engine cut off, and
- Shenzhou 17 separation.
After its trip through space, the vessel slowly approached Tiangong, docking to it at 09:46 UTC. Later, at 11:34 UTC, the crew opened the hatch so that they could ingress into the station. From this point on, the station will be shared between SZ-16 and SZ-17 crews, including the formal handover. Shenzhou 16 should return back to Earth on October 31.
What Is The Shenzhou 17 Mission?
In order to operate the Chinese orbiting lab, the national agency in charge of crewed spaceflight, CMSA, regularly launches Shenzhou spacecraft transporting crew. In this case, it is the seventeenth such flight, though not all of them carried crew. As a matter of fact, the first four were uncrewed orbital flights of varied lengths. Additionally, without humans on board, Shenzhou 8 pioneered automated docking to Tiangong-1 — a first for China.
Taikonauts On Shenzhou 17
The word taikonaut speaks of a Chinese astronaut, but English speaking media are its major users. A unit of the People’s Liberation Army (PLA), namely the Chinese Astronaut Corps, selects and trains these astronauts. So far, there have been three groups of them, with the first one from 1998 and the following one from 2010. In 2018, the selection process for the third group started.
As has been noted, three of them are flying on this mission:
Commander: Tang, Hongbo
- Age: 48
- Origin: Xiangtan, Hunan
- Qualifications: master degree, pilot, air brigade commander
- Astronaut group: 2 (May, 2010)
- Astronaut level: 1
- Previous missions: SZ-12
Mission Specialist 1: Tang, Shengjie
- Age: 34
- Origin: Dingxi, Gansu
- Qualifications: bachelor’s degree, pilot, air squadron leader
- Astronaut group: 3 (Sep, 2020)
- Astronaut level: 4
- Previous missions: –
Mission Specialist 2: Jiang, Xinlin
- Age: 35
- Origin: Qixian, Henan
- Qualifications: bachelor’s degree, pilot, deputy commander of flight battalion
- Astronaut group: 3 (Sep, 2020)
- Astronaut level: 4
- Previous missions: –
Cargo Hauled On This Mission
SZ-17’s Science And Experiments
Here is a list of major events and milestones leading to the present launch’s final countdown:
|End of 2022||–||Final assembly and testing of Shenzhou 17|
|April, 2023||–||The Long March 2F Y17 arrived at the launch site and entered stand-by for rescue mode|
|October 12, 2023||–||Tiangong performs phasing maneuvers in order to align with SZ-17’s launch; it possibly used Tianzhou 6’s engines|
|October 19, 2023||–||The rocket integrated with the spacecraft roll out to the launch platform|
|October 22, 2023||–||Joint training and inspections regarding the ground equipment involved in the launch, as well as the spacecraft|
|October 24, 2023||–||Simulation of launch preparation, launch, and flight, with the involvement of many centers, stations, and ships at sea|
Journey To Tiangong
The Shenzhou Spacecraft
China’s first and — to this date — only spacecraft capable of human transportation significantly bears the name Shenzhou. In Mandarin Chinese it is written “神舟,” with the first ideogram meaning divine, and the second, vessel or boat. Another interpretation of the name, expanded and more metaphorical, suggests a divine vessel sailing in the heavenly river. As can be seen, this is akin to the idea of the spacecraft traveling in space, with the river being the Milky Way.
The spacecraft’s operation is in charge of CMSA, while its manufacturing falls under the sphere of CASC. On the other hand, the China Academy of Space Technology (CAST) carried out its design and development. Shuguang-1 (dawn or daybreak) was in development, but the country’s context did not allow this project of a crewed capsule to ever enter production. Years later, China began funding technology projects and, in 1992, the “manned” space program was born. One of its goals specifically was to design a means of transportation for humans to go to space, and back.
After considerable debate regarding its design — going from full-blown space shuttles to two-module spacecraft — Shenzhou finally crystallized almost into its current form. CALT completed its development through a series of tests in late 1998 and early 1999, to carry out its first flight on November 19 of that year. Since that date, the vessel has been a fundamental pillar in supporting the China Manned Space Program.
Shenzhou exhibits a remarkably similar appearance to that of Soyuz, which is not surprising considering its design followed the outline of the Russian spacecraft. The Chinese development program also benefited from a technology transfer from the other nation. While both vessels feature three modules, Shenzhou surpasses Soyuz in terms of length, diameter, and span. In essence, having an aft service module, a middle reentry module, and a forward orbital module enables the spacecraft to minimize its mass during reentry. It is worth noting, this capsule is not reusable, in spite of being capable of returning to Earth.
This is a cylindrical, non-pressurized section readily distinguishable for hosting two solar arrays. The main engines reside at this module’s rear end, while 24 RCS thrusters are distributed in two positions along the module’s length. Additionally, it contains life support equipment critical for the crew.
|Length [m (ft)]||2.95 (9.7)|
|Diameter, maximum [m (ft)]||2.80 (9.2)|
|Span [m (ft)]||17.00 (56)|
|Main engine quantity [-]||4|
|Main engine thrust*** [N (lbf)]||2,500 (560)|
|Coarse RCS thruster quantity [-]||8|
|Coarse RCS thrust*** [N (lbf)]||150 (34)|
|Fine RCS thruster quantity [-]||16|
|Fine RCS thrust*** [N (lbf)]||5 (1)|
|Propellant||MMH* and N2O4**|
Located right between the other two modules, its shape resembles a bell. This is a requirement for reentry, as it enables the module to generate lift in that phase of flight, therefore providing steering capability. An ablative heat shield in its lower face protects the crew from the intense heat. The capsule can accommodate up to three taikonauts, both for ascent and descent, who will have a customized seat fabricated for each of them. Being the only section of the spacecraft that comes back to land — no other Chinese vessel can do this — it provides room for up to 50 kg (~110 lb) of “down-mass.”
A hatch is available at its top, connecting to the orbital module. Through it, the crew can access and come out of the capsule. Also on the module’s upper part, a compartment holds the parachutes needed for atmospheric deceleration, i.e., two pilot chutes, a drogue chute, a main chute, and a backup chute.
|Length [m (ft)]||2.50 (8.2)|
|Diameter, maximum [m (ft)]||2.52 (8.3)|
|Habitable volume [m3 (ft3)]||6 (210)|
|RCS thruster quantity [-]||8|
|RCS thrust* [N (lbf)]||150 (34)|
Four landing engines ensure a soft touchdown through igniting 1 m (~3 ft) above the ground. In addition to those engines, RCS thrusters provide maneuverability.
Cylindrical in shape, with conical ends, this module is at the front of the spacecraft. Two hatches are present, to the side and at the module’s bottom. The latter allows the crew access to the reentry module. The other hatch enables them to come in and out of the spacecraft. During orbital flight, the taikonauts find here a more comfortable space to live in.
It features an androgynous docking mechanism, which is at the top of the module, and essential to mate with the Tiangong station. Another hatch here is used by the crew to access the station. Additionally, this section of the spacecraft doubles as a cargo compartment, allowing the Shenzhou to carry an “upmass” of about 300 kg (~660 lb) when combined with the storage capacity of the reentry module.
|Length [m (ft)]||2.80 (9.2)|
|Diameter, maximum [m (ft)]||2.25 (7.4)|
|Internal volume [m3 (ft3)]||8 (280)|
|RCS thruster quantity [-]||16|
|RCS thrust* [N (lbf)]||5 (1)|
China Manned Space Program
Tiangong, Or China Space Station
Though it could be confused with its predecessors — Tiangong-1 and Tiangong-2 — the Chinese Space Station adds no numeral after its name: “Tian” “Gong” (天宫), meaning “Heavenly Palace.” Clearly chosen after where it will operate, this station, its modules, and some of the related spacecraft follow the naming theme:
- Tian He (天和) — Harmony of the Heavens: the first module of the Tiangong station.
- Wen Tian (問天) — Quest for Heavens: the second module, docked to Tianhe.
- Meng Tian (夢天) — Dreaming of Heavens: the module traveling on this Long March 5B.
- Xun Tian (巡天) — Touring the Heavens: a space telescope to be launched in 2024.
- Tian Zhou (天舟) — Heavenly Ship: the Chinese cargo spacecraft.
- Shen Zhou (神舟) — Divine Vessel: the Chinese crew spacecraft.
The Chinese pull lessons from other countries and the space stations they built, i.e. the Soviet/Russian Mir space station, and the International Space Station. Generally speaking, China attempts to have an optimized design for Tiangong, with better system integration. It aims at being safer for the taikonauts, allowing them to work more efficiently, while remaining a cost-effective project.
Tiangong builds on the heritage from other Chinese space stations, which were prototypes that paved the way: Tiangong-1 and Tiangong-2. A Tiangong-3 project existed, but then it saw its cancellation without ever launching. Finally the present station came into being through the launches of its three modules: Tianhe, Wentian and Mengtian.
Latest Shenzhou Flights
|June 17, 2021 – 01:22 UTC||Shenzhou 12||15|
|October 15, 2021 – 16:23 UTC||Shenzhou 13||16|
|June 5, 2022 – 02:44 UTC||Shenzhou 14||17|
|November 29, 2022 – 15:08 UTC||Shenzhou 15||19|
|May 30, 2023 – 01:28 UTC||Shenzhou 16||20|
What Is The Long March 2F?
The Long March 2F, also known as the “Shenjian,” meaning “Divine Arrow,” is a Chinese rocket and member of the Long March 2 rocket family. Designed to launch the Shenzhou spacecraft, the Long March 2F is the human-rated, two stage version of the Long March 2E rocket. The 2F is externally similar to the 2E, with the main change being the inclusion of a launch escape system. There are also some structural changes which allow the 2F to support the heavier fairing required by the Shenzhou capsule. The 2F is also capable of carrying heavier payloads thanks to the additional boosters on the first stage.
The Long March 2F has four boosters, each of which are 15.3 m (50 ft) in length, and each with one YF-20B engine. The YF-20B burns dinitrogen tetroxide (N2O4 ) and unsymmetrical dimethylhydrazine (UDMH) in a gas generator cycle. The boosters have a burn time of 128 seconds, and a specific impulse (ISP) of 291 s. Collectively the boosters produce 3,256 kN (732,000 lbf) of thrust at liftoff.
The first stage of the Long March 2F is 23.7 m (78 ft) in length and 3.4 m (11 ft) in diameter. Just like the boosters, this stage has four YF-20B engines, burning N2O4 and UDMH. This stage has a burn time of 166 seconds, and an ISP of 291 s.
The second stage is powered by a single YF-24B engine module, comprising a YF-22B engine and a YF-23B vernier, which again runs on N2O4 and UDMH. The stage is 13.5 m (44 ft) in length and 3.4 m (11 ft) in diameter, and provides 831 kN (187,000 lbf) of thrust. This stage has an ISP of 289 s, and will burn for approximately 300 seconds.