There is no limit to human potential nor to

There is no limit to human potential nor to what one would wish for or hope to conquer. Certainly this attitude drives the thought and imagination of those who are closely involved in the technical challenges of space travel . Space agencies such as the National Aeronautics and Space Administration (NASA) of the United States, the Russian Federal Space Agency (FKA or RKA), the European Space Agency (ESA), the China National Space Administration (CNSA), the Japan Aerospace Exploration Agency (JAXA), and Indian Space Research Organization (ISRO) are in the forefront of aerospace research, whatever their local political agendas may be. At their core however the basic mission of these various agencies remains consistent: to grapple with the significant problems that man will confront in adjusting to life in space. In the new frontier of space exploration, one of the great problems to be solved relates to sleep. After spending millions of years evolving to survive on a planet that turns on its axis once every 24h, all living animals have adapted to the pull of gravity towards the center of the Earth and humans have not escaped the requirements of this challenge. The question is, how will humans adapt to living in outer space where some of earth’s environmental time-keepers have been removed or drastically changed? Anthropological evidence suggests that man’s lifespan was initially much shorter than it nuciferine is today. During the Paleolithic and early Neolithic periods, the average human only lived about 30–40 years . This is not surprising in view of the harsh and frigid conditions that often prevailed in man’s immediate environment. The uncertainties of food supplies and natural resources frequently drove our primitive ancestors to seek better opportunities for survival by exploring new lands beyond the areas in which they found themselves. Humans ventured out of Africa around 125,000 years ago, and then spread out across Asia about 75,000 years ago . Eventually they traveled on to new continents and islands and ultimately populated most of the regions of this planet. Evolution of the human species has been through small physical changes to the body but accompanied by huge changes in the human brain and intelligence. The great theme of wanting to explore new frontiers has always been an enduring of man’s nature. Even ancient civilizations seem to have used ׳’, a mythological flying craft or chariot described in Hindu texts and Sanskrit epics. What we thirst for most is not to conquer the world… but to go beyond and even escapes the earth’s pull! In modern times this aspiration has turned our attention toward the heavens. Thus, while venturing into the frontier of space was at one time thought to be an impossible dream, the driving force of this idea has provided the technology to bring this dream into the realm of the possible! Over the last decade there has been an unprecedented growth in many areas of science, technology, and medicine. We have seen again and again in the newspapers and media what a particular country has accomplished on an annual basis. The next frontier is to travel to Mars. Agencies such as NASA have prioritized research that will elucidate the strategies and skills humans will require meeting the challenges of long-duration spaceflight . Similar strategies have been either adopted or are under development in by various space agencies. Accompanying the high aspirations of many nations to explore new worlds is an awareness of the equally challenging practical difficulties that would be posed by such an undertaking. One of the major questions is whether human crews will be up to the task of piloting space vehicles over the great distances involved in reaching other planets. Numerous “earthly” examples now show that crew fatigue on ships , trucks , and long-haul jetliners can lead to inadequate performance and sometimes fatal consequences , a reality which has caused many of the space agencies to take the issue of sleep seriously.