The last five decades have witnessed many feats in the human space- flight program, the world over. Capsules have evolved from Vostok to Soyuz in Russia; in the US, flights began in capsules like Mercury, Gemini etc.. They culminated in the Apollo program for manned missions to the Moon. The Russian Soyuz vehicle has made many trips to earth's low earth orbits with humans on board and is currently the only operational human space transportation system available to humanity. The era has also witnessed the entry and exit of the USA's winged Space Transportation System – the Space Shuttle and the construction of the International Space transportation System (ISS) with the involvement of some of the space- faring nations. With the successful launch of manned 'Shenzhou', China has also entered the fray as the third country possessing the capability to have human access to space. Of late, more and more countries have shown a keen interest and taken up serious studies to develop the capability to have human access to space. The last decade has also seen an increased role being played by private agencies in the USA, investing significantly in manned space missions.
There are many challenges to human spaceflight programme, especially when the targets are beyond the Earth. Apart from the cost involved, the development of reliable transportation systems, the need for new technologies, and the destination also became the topics of discussion. Beyond LEO (Low Earth Orbit; an Earth-centered orbit with an altitude of 2,000 km or less), the Moon, Mars, the cis-lunar space (the region outside Earth's atmosphere and extending out to the volume within the Moon's orbit), the Lagrange points (in the space, there are points where the gravitational forces of two celestial bodies produce regions of attraction and repulsion equaling the centripetal force required for a small object to move with them, which can be used by a spacecraft to reduce the fuel consumption needed to remain in position), and near-earth objects, like some Asteroids, have been targeted for future human exploration.
Gaganyaan is the Indian human space flight programme that envisages to put three astronauts into a 400 km low earth orbit and bring them back safely to earth after spending seven days in space. The orbital module has two parts – the crew module, where the crew will be residing; and, the service module, which will service the crew module during the orbital phase. There will be two identical unmanned flights before undertaking the manned flight. The manned flight is scheduled in December 2021. There will be sustained human space flight activities after Gaganyaan, including the long-duration manned space missions and construction activities in space.
When human beings are involved, the focus shifts to the safety of crew at any stage of the flight. Viable escape provisions shall be incorporated into the launch vehicle to ensure the safe bailing out of the crew in case of any exigencies. The escape system will be designed as a simple system and will be extensively tested to ensure a faultless performance, in case it is called into action.
The selected astronaut candidates will be trained to face various conditions that are likely to be encountered in the mission, including the physiological and psychological aspects affecting the crew. These aspects become more dominant depending upon the destination of mission and its duration. The long-term impact of space and its environment including galactic radiation, isolation, changes in circadian rhythm, bone loss and associated problems, anxiety, etc., pose many opportunities for the medical professionals to carry out research and development in many emerging areas of Bioastronautics.
There is ample scope for biomedical professionals to initiate activities in many disciplines of human sciences that will benefit the human space flight activities of India.
© Neurology India , Year: 2019 / Volume : 67 / Issue : 8