pstp sci aviation space med "In order for passengers in a plane to experience a free fall safely, the aircraft must climb at a steep angle, level off, and then dive, creating a path called a parabolic arc, also called a Keplerian Trajectory or free-fall path. In a true parabolic arc, the only accelerative force is gravity pulling in a vertical direction -- horizontal velocity remains constant. Because of air resistance, objects in Earth's atmosphere only travel in arcs that approximate a true parabola. Typically, ZERO-G's plane, called G-FORCE-ONE, flies between 24,000 and 32,000 feet altitude. This gives the pilot enough room to maneuver the plane safely through its flight path. The plane's descent must start at a high altitude to provide enough distance for the pilot to safely pull out of a dive. As the plane climbs to the peak of its arc, the pilot orients it at a 45-degree angle. During the climb, the plane's acceleration and the force of gravity create a pull 1.8 times the strength of gravity alone -- passengers temporarily weigh nearly twice as much as normal. Photo courtesy of Zero Gravity Corporation A passenger aboard the G-FORCE-ONE As the plane goes over the top of the arc, the centrifugal force exerted on the plane and everything in it cancels out the gravitational force pulling downwards. At this point, passengers experience microgravity -- it feels as if you are weightless because only negligible gravitational forces are present. The sense of weightlessness lasts for about 30 seconds. Because the plane shields the passengers from the rush of air, they can experience a free fall without the interference of air resistance. The pilot pulls the plane out of the dive so that the dip between one arc and the next is at about 24,000 feet altitude. As the plane pulls out of the dive and begins to climb again, passengers again experience the force of 1.8 times that of gravity. The typical ZERO-G flight includes 15 of these parabolic arcs, while NASA flights may include up to 100." - Thomas Page

http://www.ncbi.nlm.nih.gov/pmc... It is important to distinguish between “freefall” and “weightlessness.” Even in orbital flight, for example when the Space Shuttle orbits 300 km above the Earth's surface, gravity is only slightly less than at sea level (9.37 m/s2 compared to 9.81 m/s2 at sea level). Thus terms like “microgravity,” “zero-gravity,” and “weightless” are technically incorrect when applied to orbital flight (and atmospheric aircraft maneuvers), although they are often used to describe the perception that astronauts experience during freefall. Spacecraft in Earth orbit are continually falling toward the earth under the force of gravity, but are given sufficient forward velocity so that the sum of their velocities toward and parallel to earth keeps them at the same distance from earth; as the spacecraft falls toward the earth, the earth curves away from under it. Astronauts perceive themselves to be weightless because they are falling under the influence of the same gravitational field as the spacecraft, so there is no reaction force on the astronaut by the spacecraft. According to Einstein's equivalence principle, no simple physical transducer can determine whether an applied acceleration is due to gravitational or inertial force, and this includes the sensors in the human body. Gravito-inertial acceleration (GIA), often expressed simply as g level, is defined as the sum of the linear accelerations due to gravity and inertial forces. It is measured in units of g, where 1 g = 9.81 m/s2 at sea level. During freefall the net g level is 0 g, but gravity is not zero. , Heinz Haber http://en.wikipedia.org/wiki... , http://history.nasa.gov/SP-4201... , http://www.christa.org/gravity... , http://en.wikipedia.org/wiki... - Thomas Page

New Software May Help Astronauts Stay Strong in Space http://news.yahoo.com/s... , 7 -7 http://humanresearchroadmap.nasa.gov/ , 8 -6 Staying in Shape in Space With Astronaut Clay Anderson http://www.planetary.org/radio... 6 -20 http://mashable.com/2014... - Thomas Page

How Much Is an Astronaut’s Life Worth? NASA’s irrational approach to risk undermines its mission and costs thousands of lives. http://reason.com/archive... , 2 -11 Astronaut feels space's toll on his body http://lightyears.blogs.cnn.com/2012... http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... [[[[ 6 -2 calamity failure engineering http://www.nytimes.com/2014... - Thomas Page

Space Food https://en.wikipedia.org/wiki... [ sort Astronaut Chris Hadfield and Chef Traci Des Jardins Make a Space Burrito https://www.youtube.com/watch...! Tasting Astronaut Food: Inside NASA's Space Food Systems Laboratory https://www.youtube.com/watch... https://www.youtube.com/watch... , http://en.wikipedia.org/wiki... , 9 -13 The Architecture of Artificial Gravity: Theory, Form, and Function in the High Frontier http://www.spacefuture.com/archive... http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... - Thomas Page

12 -25 http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... [[ 2 -16 -14 Astronauts Wives booktv ? http://www.goodreads.com/book... http://www.c-span.org/video... 2 -19 http://www.dailymail.co.uk/tvshowb... - Thomas Page

Astronaut Chris Hadfield http://en.wikipedia.org/wiki... http://www.sciencefriday.com/segment... http://www.npr.org/2013... http://www.openculture.com/2013... 11 -6 Chris Hadfield: What I learned from going blind in space http://youtu.be/Zo62S0ulqhA 12 -10 http://www.nytimes.com/2014... - Thomas Page

Edgar Mitchell http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... [ http://en.wikipedia.org/wiki... [[ http://en.wikipedia.org/wiki... 11 -8 http://en.wikipedia.org/wiki... - Thomas Page

. - Thomas Page

5 -12 http://en.wikipedia.org/wiki... - Thomas Page

Intermittent Movement Benefits Your Health. Here’s How to Get More of It into Your Work Day http://fitness.mercola.com/sites... it appears that temporary vigorous exercise can't even compensate for the damage incurred by prolonged daily sitting! In fact, it's becoming increasingly clear that staying active—and by that I mean engaging in virtually any physical movement—as much as possible, throughout the day, is critical for health and longevity. It even appears to be more important, in the big scheme of things, than a regularly scheduled fitness routine... locomotion sort http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... - Thomas Page

9 -5 effects_of_spaceflight http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... http://en.wikipedia.org/wiki... [ Team_composition_and_cohesion_in_spaceflight_missions http://en.wikipedia.org/wiki... [[[[ http://en.wikipedia.org/wiki... - Thomas Page

Sort Astronaut_training http://en.wikipedia.org/wiki... seriousness of purpose http://www.nasa.gov/mission... http://www.nsbri.org/NEWS-an... http://abcnews.go.com/Technol... http://astronauts.nasa.gov/content... - Thomas Page

The first seven American astronauts were an admirable group of individuals chosen to sit at the apex of a pyramid of human effort. In training to transcend gravity they became a team of personalities as well as a crew of pilots. They were lionized by laymen and adored by youth as heroes before their courage was truly tested. In volunteering to entrust their lives to Mercury's spirit and Atlas' strength to blaze a trail for man into the empyrean http://en.wikipedia.org/wiki... ,they chose to lead by following the opportunity that chance, circumstance, technology, and history had prepared for them. Influential 20th-century philosophers as diverse as Bertrand Russell, Teilhard de Chardin, and Walter Kaufmann tell us that man's profoundest aspiration is to know himself and his universe and that life's deepest passion is a desire to become godlike. All men must balance their hubris with their humility, but, as one of those aspiring astronauts said, "How could anyone turn down a chance to be a part of something like this?" Shortly after the astronauts were introduced to the public, a literate layman asked directions of Mercury for mankind in general: Which way will heaven be then? Up? Down? Across? Or far within? http://www.nasa.gov/mission... [[[[ 9 -8 sort http://en.wikipedia.org/wiki... 12 -29 http://www.theatlantic.com/feature... - Thomas Page