The objective of the second phase of CMS was to achieve technological breakthroughs in spacewalk (EVA) activities, space rendezvous and docking to support short-term human activities in space. [10] On September 25, 2008, on the flight from Shenzhou 7, Zhai Zhigang and Liu Boming completed China`s first EVA. [11] In 2011, China launched the Tiangong 1 target probe and the unmanned Shenzhou 8 spacecraft. The two spacecraft completed China`s first rendezvous and automatic docking on November 3, 2011. [12] About 9 months later, Tiangong 1 completed the first manual rendezvous and docking at Shenzhou 9, carried by china`s first female astronaut Liu Yang. [13] Robot-assisted space exploration has become a serious space exploration heavyweight. While shuttle launches and the International Space Station receive all the media coverage, these small, relatively inexpensive unmanned missions operate in the background of important scientific discoveries. The last major media event to promote manned flight was Senator John Glenn`s trip in 1998 – ostensibly to study the effects of space travel on the human body, but widely regarded by scientists as nothing more than a publicity stunt. In a weightless environment, astronauts place almost no weight on the back or leg muscles used to stand up, weakening the muscles and shrinking them. Astronauts can lose up to twenty percent of their muscle mass during five- to eleven-day space flights. The resulting loss of power could be a serious problem in the event of a landing emergency. [68] Upon returning from long-term flights to Earth, astronauts are significantly weakened and are not allowed to drive a car for twenty-one days. [69] The first man in space was Soviet cosmonaut Yuri Gagarin, who was launched on April 12, 1961 at the beginning of the space race as part of the Soviet Union`s Vostok program.

On May 5, 1961, Alan Shepard became the first American in space as part of Project Mercury. Humans traveled to the Moon nine times between 1968 and 1972 as part of the U.S. Apollo program and were continuously present in space on the International Space Station (ISS) for 21 years and 343 days. [2] On October 15, 2003, China`s first taikonaut, Yang Liwei, went into space as part of Shenzhou 5, China`s first manned space flight. In 2021, humans have not traveled beyond low Earth orbit since the Apollo 17 lunar mission in December 1972. Technology and economic development have a similar status. First, the opportunity cost; If the U.S. government wants to invest in technology, it can do so in other, more direct ways. The development of space-sustaining technologies or lunar dust-washer systems, for example, is not as likely to generate returns for terrestrial applications as direct investments in the production of solar cells or new biomaterials. To date, more than 20 scientific organizations around the world have spoken out against the space station and recommend using the funds for larger unmanned missions.

In 30 years, NASA`s fleet of space shuttles – Columbia, Challenger, Discovery, Atlantis and Endeavour – has flown 135 missions and transported 355 different people into space. The Space Shuttle, humanity`s first reusable spacecraft, has repeatedly launched humans into orbit; satellites launched, recovered and repaired; conducted cutting-edge research; and built the largest structure in space, the International Space Station. The Space Shuttle has pushed the boundaries of discovery further and further, requiring not only cutting-edge technologies, but also the considerable efforts of thousands of officials and contractors in NASA`s field centers and across the country. Tragically, NASA lost two out of seven crews in the 1986 Challenger accident and the 2003 Columbia accident. TRW is currently building Hubble`s successor, the Jack Web Space Telescope (formerly the Next Generation Space Telescope). It is planned to launch it in 2010 and put it into L2 orbit – a much better position to study stars. With L2 or Lagrange Point 2, it only needs a simple shield instead of the complicated cooling system hubble needs because of its proximity to Earth. It will also be out of range of the Space Shuttle in the event of a problem, as was the case with the Hubble mission. On November 2, 2017, based on MRI studies, scientists reported that significant changes in brain position and structure were found in astronauts who made space trips.