On September 15, 2016 (August 15, 2016 in the lunar calendar), the Tiangong-2 Space Laboratory was successfully launched. At 22:04 on September 15, 2016, the Long March-2 FT2 carrier rocket carrying the Tiangong-2 Space Laboratory was ignited and launched at the Jiuquan Satellite Launch Center. About 575 seconds later, the Tiangong-2 successfully separated from the rocket and entered the predetermined orbit. The launch was a complete success. Data map: On September 9, the launch vehicle carrying out the Tiangong-2 mission was vertically transferred to the launch area of the Jiuquan Satellite Launch Center Manned Space Launch Site. It is planned to launch from September 15 to 20. "Tiangong-2" has arranged more than ten high-tech tasks in the fields of earth science observation and applications, space science experiments and detection, and application of new technologies. Some of these experiments are exploring the deepest mysteries of the universe, and some are helping people better. Understand the ocean and atmosphere, and some are even solving the problem of food during future interstellar travel. China scientists will carry out more than ten high-precision experimental missions in it, which is the largest number of application projects in any manned space mission. After the launch of Tiangong-2 is completed, the Shenzhou-11 spacecraft will send the astronauts into space, and then it will rendezvous and dock with Tiangong-2. After that, the astronauts will enter Tiangong-2 and start a series of scientific experiments. Zhu Zongpeng, chief designer of the Tiangong-2 Space Laboratory of the Fifth Academy of China Aerospace Science and Technology Corporation, said in an interview with the media that Tiangong-2 mainly has three major tasks: "Tiangong-2 is my country's first space laboratory, and the tasks it completes are mainly medium-term residency. The astronauts rendezvous and docked on the Shenzhou 11 spacecraft and worked and lived on Tiangong-2 for 30 days. This is a medium-term residency task. The second is to dock with the cargo spacecraft next year to carry out on-orbit replenishment of propellant. The third is to conduct some technical tests for the future space station, including some maintenance related tests." You may still remember that in the movie "Mars Rescue", the protagonist overcame many difficulties alone, survived by growing potatoes on the Mars base, and finally returned to Earth. At present, the territory of human space exploration continues to expand, from low-earth orbit to deep space exploration, from establishing a lunar base to survival on Mars. As the saying goes,"before the soldiers and soldiers move, food and grass come first." If humans want to fly out of the earth, travel between stars, and immigrate to outer planets, the primary task is to solve problems such as food self-sufficiency, oxygen and recycled water. Can green plants on earth grow normally in the space environment, providing humans with a source of food and oxygen? Although many plant growth experiments have been carried out in space, to successfully achieve the production of grain and vegetables in space conditions, many problems such as the impact of extreme environmental factors, including microgravity, on plant growth and development need to be solved. The advanced plant culture experiment to be carried out in the Tiangong-2 Space Laboratory this time is to study this issue. Tiangong-2 Space Laboratory Plant Culture Experiment The gravitational environment outside the earth includes microgravity, low-gravity and overweight "plant astronauts"-rice and Arabidopsis. China is accustomed to eating rice, so everyone is familiar with rice and another A higher plant with different growth characteristics, Arabidopsis thaliana, was lucky to be elected as a "plant astronaut" and will carry Tiangong-2 on an extraordinary space journey. Data map: The left picture shows Arabidopsis thaliana, and the right picture shows the higher plant incubator carried by the rice Tiangong-2. It is a miniature version of the space greenhouse. It has an important responsibility and will carry out my country's first six-month plant "from seed to seed" Full life cycle cultivation. Scientists will be able to directly observe the germination, growth, flowering and seed setting of different plant seeds in space, so as to better understand and grasp the possibilities of future space agriculture development. Data map: The higher plant incubator is divided into an on-orbit unit and a return unit. The on-orbit unit can provide two Arabidopsis culture units and two rice culture units, with one long-day and one short-day culture conditions respectively (such as the plant culture schematic diagram on the right), and the return unit is used to cultivate Arabidopsis. The higher plant incubator (left picture) is divided into an on-orbit unit and a return unit. The on-orbit unit can provide two Arabidopsis culture units and two rice culture units, with one long-day and one short-day culture conditions respectively (such as the plant culture schematic diagram on the right), and the return unit is used to cultivate Arabidopsis. How does the experiment proceed? Rice and Arabidopsis seeds carefully selected by botanists on the ground will ride in a comfortable and warm "warm box" while dormant as Tiangong-2 enters orbit. Scientists will remotely command from the ground to start the experimental process and seeds will begin to germinate. In the following period of time, the incubator provides environmental protection for the growth and development of seeds through functions such as temperature, humidity, light, and nutrient supply regulation. It is expected that after 1-2 months, if the growth is smooth, the plant will enter the bolting (ear) flowering stage. Higher plant incubators can realize real-time monitoring of the entire process of plant growth and development. Cameras and other measuring components will conduct "full live broadcast", recording images, temperature changes and other data, and uploading it to the ground for botanists to conduct comparison and analysis. Schematic diagram of the growth cycle of a long-day plant Arabidopsis (left) and pictures of Arabidopsis plants at different growth and development periods (right). Schematic diagram of the growth cycle of a long-day plant Arabidopsis (left) and pictures of Arabidopsis plants at different growth and development periods (right). Schematic diagram of the growth cycle of short-day plant rice (left) and rice in flowering stage (middle). The rice varieties cultivated in the Tiangong-2 Space Laboratory are dwarf rice mutants (d18h), and the rice plant height during maturity is 15-20 cm (the dwarf rice was provided by researcher Qian Qian of China Rice Research Institute). The right picture shows the comparison between dwarf rice and normal plant height rice (zh11) during the seedling stage. Schematic diagram of the growth cycle of short-day plant rice (left) and rice in flowering stage (middle). The rice varieties cultivated in the Tiangong-2 Space Laboratory are dwarf rice mutants (d18h), and the rice plant height during maturity is 15-20 cm (the dwarf rice was provided by researcher Qian Qian of China Rice Research Institute). The right picture shows the comparison between dwarf rice and normal plant height rice (zh11) during the seedling stage. What is the magic of a space greenhouse? In a space greenhouse, a growth box is a space where plants grow. It is made of transparent materials. The light source shines from the top and the camera takes pictures from the side. A breathable film is attached to the growth box to ensure a certain amount of gas exchange between the plants and the greenhouse, while liquid water will not escape from the breathable film, so as to ensure the moisture needed during plant growth. In the space microgravity environment, water vapor produced by transpiration during plant growth cannot condense and return to the soil, but adheres to the side of the growth box and affects imaging. In order to solve this problem, scientists have increased the design of the condensation zone to re-condense the water vapor and introduce it into the soil box, which has achieved effective circulation of water in a closed environment in space, improved water utilization, and avoided possible adverse effects caused by water vapor. It is really efficient and safe. Real-time image of the growth process of dwarf rice (d18h) in a higher plant incubator. The image records rice from seed germination to growth for 26 days. Real-time image of the growth process of dwarf rice (d18h) in a higher plant incubator. The image records rice from seed germination to growth for 26 days. Install "trackers" for genetic information Botanists have previously used transgenic technology to mark the flowering gene of Arabidopsis thaliana with the green fluorescent protein gene. The incubator is equipped with a miniature fluorescent camera and integrated with an LED fluorescent excitation light source. Once the Arabidopsis flowering gene is expressed, it will be excited to emit green fluorescence by the LED light source. Fluorescent cameras can capture fluorescent signals and transmit information. a and b are images of Arabidopsis thaliana plants in the same culture box by visible light and fluorescence cameras, respectively. c indicates different Arabidopsis plants in the culture box, WT is common Arabidopsis without green fluorescent protein gene marker, FTPro::GFP is transgenic Arabidopsis containing green fluorescent protein. a and b are images of Arabidopsis thaliana plants in the same culture box by visible light and fluorescence cameras, respectively. c shows different Arabidopsis plants in the culture box, WT is ordinary Arabidopsis without green fluorescent protein gene marker, and FTPro::GFP is transgenic Arabidopsis containing green fluorescent protein. Astronauts will also participate in the experiment. Our astronauts will carry out the first recovery of some Arabidopsis experimental samples in the Tiangong-2 space laboratory. Experimental samples of Arabidopsis thaliana cultured in space will be returned to the ground with the return unit for subsequent research and analysis, providing first-hand materials for understanding the seed development and nutrient storage of higher plants under space microgravity conditions. Future Outlook More than 40 years have passed since humans landed on the moon, and now the dream of returning to the moon and landing on Mars has swept the world. Some scientists have not only drawn up blueprints for lunar and Mars bases, but have also completed site selection. How to establish a closed space ecological circulation system based on green higher plants to provide supplies for astronauts 'long-term space life? This is a huge comprehensive project. my country's development in the aerospace and space fields has provided unprecedented opportunities for space life science research. Strengthen research on plant growth and development in the space environment, break through the technical bottleneck of the space life ecological support system, and build a new world for mankind's long-term survival outside the earth. Humanity's dream of crossing the sky will surely become a reality in the near future.