CBN Friday Special丨Wentian lab module: new breakthrough in China’s space quest

S: Hi everyone. Welcome to CBN Friday Special. I’m Stephanie LI. 

K: Hi, I’m Kathy.

S: Hey Kathy. Did you watch the launch of Wentian lab module on Sunday? What a magnificent spectacle, also an exiting moment for all Chinese people. 

K: Of course. China launched the second of three modules to its permanent space station over last weekend, in one of the final missions needed to complete the orbiting outpost by year's end. 

A live feed on state broadcaster CCTV showed the 23-ton Wentian module launching on the back of China's most powerful rocket, the Long March 5B, at 2:22 p.m. from the Wenchang Space Launch Center in China’s southernmost island province Hainan.

As I was watching the rocket blasting off to space on television, amateur photographers and space enthusiasts watched onsite as it lifted off to join the Tiangong space station, or Heavenly Palace in Chinese. 

S: Wentian, or "Quest for the Heavens", is the first lab component of Tiangong space station, which will function both as a backup of the core module and as a powerful scientific experiment platform. 

The Wentian module has already set multiple new world records. With a length of 17.9 meters, Wentian is the world's longest single-body manned spacecraft. The 23-ton Wentian lab module is heavier than any other single-module spacecraft currently in space, including those with the International Space Station (ISS), according to the mission contractor, the state-owned space giant China Aerospace Science and Technology Corp (CASC).

K: The main task of Wentian module is to uniformly manage and control the space station assembly, and provide special airlock cabins and emergency shelters to support astronauts to stay in orbit and ensure their safety. In addition, it also has the function of conducting scientific and technical experiments inside and outside the sealed cabin. 

For the internal design, the typical feature of Wentian is that it integrates the platform function and the test load function. The main equipment in the cabin is arranged in the work cabin, loaded with eight experimental cabinets, as well as the equipment required for the flight. 

Besides, Wentian provides one more exit, one more kitchen, one sanitary area, one emergency shelter, as well as three sleeping zones for the astronauts, thus greatly extending the living and working space for them.

S: China began constructing the space station in April 2021 with the launch of the Tianhe module, the main living quarters, in the first of 11 crewed and uncrewed missions in the undertaking.

As a member of the "China Space Station" family, Wentian and other family members play different roles. The basic configuration of the Chinese space station is the Tianhe core module, Wentian module and Mengtian module, which means “Dreaming of the Heavens”. 

The Tianhe core module launched on April 29, 2021, is the most important part of the space station, and other modules will be installed on its interface, which is also the main living space of astronauts. The key platform functions of Wentian and Tianhe are the same, which can fully cover the working requirements of the space station assembly.

Wentian is designed mainly for the study of space life sciences, which can support the growth, development, genetics and aging of multiple species of plants, animals and microorganisms under space conditions. More than 10 research directions have been planned and more than 40 scientific projects have been established for the Wentian. 

Mengtian, which is expected to be launched in October and, like Wentian, is to dock with Tianhe, forming a T-shaped structure and mainly used for microgravity research. 

K: At 3:13 on Monday, the rendezvous and docking between Wentian and the Tianhe core module were completed. About 7 hours later, the astronauts of Shenzhou 14 successfully opened the door and entered the module. So, why didn't the astronauts enter Wentian immediately after rendezvous and docking? 

S: Good question. In fact, when astronauts enter the module for the first time, they need to start the harmful gas purification function in advance and ensure that all channel pressures are balanced. 

After entering the module, the astronauts have to carry out busy sorting work, including material handling, living environment layout, preparation work for scientific experiments and extravehicular activities, etc. Speaking of work, what do you know about the astronauts' mission this time?

K: Well, after the astronauts successfully enter the module, they will mainly carry out a series of research, mainly including four fields: space life science and biotechnology, microgravity fluid physics, space material science, and space application of new technology experiments. 

S: Wow, that should keep the astronauts very busy for a while. By the way, the working environment of the astronauts in Wentian has also been comprehensively upgraded. 

The upgrades include sound absorption, noise reduction and shock absorption. The module is also equipped with a special airlock for astronauts, so they can get in and out more easily and operate more conveniently.

Like the Tianhe core module, Wentian is also equipped with a mechanical arm, which not only reduces the working intensity and risk of astronauts but also flexibly and efficiently supports the extravehicular load test.

K: To meet the high energy requirements for the large number of scientific experiments in space, Wentian is equipped with a pair of the largest flexible solar panels that the country has ever developed. 

It also carried four big tools with a weight of more than 100 kilograms, which are called control moment gyros. The combined use of 12 control moment gyros can effectively reduce the use of fuel, and achieve the effect of energy saving. China is the third country in the world that can apply this technology. 

S: The success of Wentian's extraordinary launch is of great significance to China's aerospace industry because this is the first lab module of China's space station. 

This is also the first time that China's two spacecrafts have achieved rendezvous and docking in orbit, and it is also the first time that space rendezvous and docking have been carried out during the space station's astronauts' stay in orbit. 

Besides, the launch has to be a zero-window launch, because Wentian needs to rendezvous and dock with the space station Tianhe core module. Otherwise, it will not be able to reach the specified position, and it will cost a lot of money to adjust the orbit; even leading to its termination. 

The successful docking indicates that China is one step closer to the goal of fully completing the on-orbit construction of the space station. 

K: There was a time when China had little chance to do such research. Now China can.

A browse at the past 10 years will find a clear path for China's space industry. In 2003 China became the third country to launch an astronaut into orbit on its own accord, after the former Soviet Union and the US. 

The Shenzhou series of spaceships has progressed from IX to XIV, while the space station is finally coming into service. Besides, there is also the Zhurong martian probe, Xihe solar exploration satellite, as well as the Chang'e lunar probe. The Chinese are adding more footprints in space, for the common good.

S: 2022 is the decisive year for the construction of China's space station and also the 30th anniversary of the establishment and implementation of China's manned space project. The latest information released by the National Space Administration shows that more than 60 launch missions are planned this year.

The China Space Station is planned to become fully operational before the end of 2022, aiming to accomplish the in-orbit assembly of the country's most ambitious program in less than one year and a half since the launch of the Tianhe core module in April 2021. After the decommissioning of the international space station in 2024, the Chinese space station will become the only space station in space. 

Before China, only the former Soviet Union and the US were capable of assembling ultra-large spacecraft in orbit. In the coming months, people on Earth will be able to witness the construction of the China Space Station, which will be completed at a speed that has no precedent in mankind's history. 

And that’s it for today, see you next time. 

“问天”问天！

2022年7月24日14时22分，一声“点火”令下，问天实验舱发射取得圆满成功，成为中国空间站的第二名“成员“。此次发射的问天实验舱是我国载人航天工程立项实施以来的第24次飞行任务，也是中国航天员首次在轨进入科学实验舱。纵然烈日当头，还是有许多人顶着酷暑，来到海南文昌发射中心现场，现场“目送”问天升空。

这位新的空间站成员究竟长什么样呢？先来看它的“威风凛凛”!

作为中国首个科学实验舱，问天实验舱背负重任，因此体量非常大，设计也更加复杂。实验舱舱体总长17.9米，直径4.2米，发射重量约23吨，是我国目前最重、尺寸最大的单体飞行器。除此之外，它配备的一对双自由度柔性太阳帆板，全部展开后的翼展超过55米，比半个足球场还要长。另外，实验舱外部署的能量粒子探测器、等离子体原位成像探测器，为航天员健康、空间站安全运营提供保障支持，并可用于空间环境基础研究。 

接下来，咱们再看它的“五脏俱全”。

问天的典型特点就是集平台功能与试验载荷功能于一体。问天实验舱由工作舱、气闸舱和资源舱组成，主要用于支持航天员驻留、出舱活动和开展空间科学实验，同时可作为天和核心舱的备份，对空间站进行管理。舱内装载了8个实验柜，包括生命生态实验柜、生物技术实验柜、变重力科学实验柜、科学手套箱、低温存储柜以及3个为后续预留的空置实验柜。还有3个睡眠区、1个卫生区、厨房和紧急避难所，以及平台飞行所需要的设备。

那么，问天上天，何问也？

由于太空环境和地球迥异，人类若要逐梦深空，开启地外生活，须先进行一系列空间生命科学实验和研究，因此，“问天”此次上天与天和核心舱会合后，将支持航天员开展密封舱内、舱外科学实验和技术试验。舱内的8个宽1米、高1.8米、深0.8米的生命生态实验柜和生物技术实验柜中，配置了9个如同抽屉一般的科学实验模块，它们承担着实验和研究的重任。

问天实验舱以生命科学和生物技术研究为主，在空间生命科学与生物技术、微重力流体物理、空间材料科学、空间应用新技术试验等4个领域规划部署了10余个研究主题，目前已立项40余项科学项目，空间站建成后将持续论证、滚动实施相关科学项目。

以生物技术科学实验系统为例，细胞组织培养、空间蛋白质结晶与分析等实验都将在问天实验舱展开。其中，细胞组织实验模块作为核心实验模块，可同时支持72个培养单元开展空间细胞、组织层面的培养实验。对此，结构工程师张寅幽默地将它比作是一栋有36套72间房的“精装楼”，细胞组织可以直接“拎包入住”，还可以根据需求更换“住户”。

此外，生命生态科学实验系统亦是“神通广大”，主要包括通用生物培养模块这一核心在内的六大模块。通用生物培养模块则可对植物生长所需气体组分进行动态调控，并根据不同科学实验进行调整，前期将开展高等植物种子、幼苗或植株的培养，后期可根据需要对线虫等微小动物开展培养。总的来说，生命科学实验系统相当于建立一个相对完备的基础生物科学实验室，将助力人类耕渔太空。

为了让科学实验更好地开展，问天实验舱为神州十四号航天员的生活和实验提供了更优的环境。对在轨航天员来说，两舱对接形成组合体，意味着太空家园从“一居室”升级到更宽敞的“两居室”。问天实验舱的工作舱内设有3个睡眠区和1个卫生区。完成对接后，空间站后续可以支撑神舟十四号、十五号两个乘组6名航天员实现“太空会师”和在轨轮换，在太空面对面交接工作。

另外，问天实验舱在吸音、降噪、减震等方面也进行了优化升级。问天实验舱还配置了一个出舱人员专用的气闸舱。航天员不仅进出更舒展从容，也更易携带大体积的设备出舱工作。进出舱门的操作也更加简单、便捷。不仅如此，气闸舱外的暴露实验平台还配置了22个标准载荷接口，可以通过机械臂精准‘投送’到自己对应的载荷接口位置，不再需要航天员出舱进行人工操作。这样，既降低了航天员的工作强度和风险，又可以灵活高效支持舱外载荷试验。

星辰浩瀚，920亿光年是人类可观测到的宇宙规模，是目前人类已知的最为广阔的空间。2022年是中国空间站建造的决胜之年，问天代表着中国航天人无限的智慧、信心与勇气，肩负着决胜中国空间站建造的时代重任，再次向这片苍穹发出响彻云霄的探问。