Saturn V rocket, used for the American manned lunar landing missions The Moon as seen in a digitally processed image from data collected during a spacecraft flyby While the observation of objects in space, known as astronomy, predates reliable recorded history, it was the development of large and relatively efficient rockets during the early 20th century that allowed physical space exploration to become a reality. Common rationales for exploring space include advancing scientific research, uniting different nations, ensuring the future survival of humanity and developing military and strategic advantages against other countries. Space exploration has often been used as a proxy competition for geopolitical rivalries such as the Cold War. After the first 20 years of exploration, focus shifted from one-off flights to renewable hardware, such as the Space Shuttle program, and from competition to cooperation as with the International Space Station (ISS). First flights
Health threat from cosmic raysThe health threat from cosmic rays is the danger posed by galactic cosmic rays and Solar energetic particles to astronauts on interplanetary missions. Galactic cosmic rays (GCRs) consist of high energy protons (85%), helium (14%) and other high energy nuclei HZE ions. Solar energetic particles consist primarily of protons accelerated by the Sun to high energies via proximity to solar flares and coronal mass ejections. They are one of the most important barriers standing in the way of plans for interplanetary travel by crewed spacecraft. The deep-space radiation environment Sources of ionizing radiation in interplanetary space. The radiation environment of deep space is very different from that on the Earth's surface or in low Earth orbit, due to the much larger flux of high-energy galactic cosmic rays (GCRs), along with radiation from solar proton events (SPEs) and the radiation belts. Human health effects Central nervous system Mitigation Drugs
WeightlessnessA block of lead in free fall on planet X. The block is said to be in a state of weightlessness although being pulled down by the planet's gravity. Two bodies in free fall: the Earth and the Moon. The two bodies are GR inertial and are accelerating towards each other.[a] They are approximately weightless. Weightlessness, or an absence of 'weight', is in fact an absence of stress and strain resulting from externally applied forces, typically contact forces from floors, seats, beds, scales, and the like. When bodies are acted upon by non-gravitational forces, as in a centrifuge, a rotating space station, or within a space ship with rockets firing, a sensation of weight is produced, as the forces overcome the body's inertia. When the gravitational field is non-uniform, a body in free fall suffers tidal effects and is not stress-free. Weightlessness in Newtonian mechanics In the left half, the spring is far away from any gravity source. Stress during free fall 1. 2. Relativity
Space medicineNASA astronaut Dan Burbank (foreground), Expedition 30 commander, and Russian cosmonaut Anton Shkaplerov, flight engineer, participate in a Crew Health Care System (CHeCS) medical contingency drill in the Destiny laboratory of the International Space Station. This drill gives crewmembers the opportunity to work as a team in resolving a simulated medical emergency on board the space station.(Nasa) Space medicine is the practice of medicine on astronauts in outer space whereas astronautical hygiene is the application of science and technology to the prevention or control of exposure to the hazards that may cause astronaut ill health. Both these sciences work together to ensure that astronauts work in a safe environment. History Benefits Astronauts are not the only ones who benefit from space medicine research. Medical space spinoffs (pre-Mercury through Apollo) Medical investigations in space during the Space Shuttle era Effects of space-travel Barotrauma
Astronautical hygieneAstronautical hygiene is the application of science and technology to the recognition and evaluation of hazards, and the prevention or control of risks to health, while working in low-gravity environments (Ref: Cain, John R. "Astronautical hygiene-A new discipline to protect the health of astronauts working in space", JBIS, 64, 179-185, 2011). Space medicine has developed as a science since 1948 when Dr. Overview When astronauts return to the Moon and travel farther to Mars, or even other planets, they will be exposed to a number of hazards e.g. radiation, microbes in the spacecraft, planetary surface toxic dust. The Space Shuttle is to be replaced in 2014 by a new spacecraft, the Orion Multi-Purpose Crew Vehicle, to carry astronauts to the International Space Station. Dr. Hygiene in space Issues arise when dealing with low gravity environments. Control of gases in spacecraft Exposure limits are based on: "Normal" spacecraft operating conditions.An "emergency" situation.
Human spaceflightISS crewmember views the Earth, 2010 computer generated illustration of a potential human Mars exploration. Human spaceflight (e.g. manned spaceflight) is space travel with humans aboard spacecraft. Humans have been continually present in space for 700113000000000000013 years and 7002165000000000000165 days on the International Space Station. In recent years there has been a gradual movement towards more commercial means of spaceflight. History First human spaceflights The first human spaceflight took place on 12 April 1961, when cosmonaut Yuri Gagarin made one orbit around the Earth aboard the Vostok 1 spacecraft, launched by the Soviet space program. The United States became the second nation to achieve manned spaceflight with the suborbital flight of astronaut Alan Shepard aboard Freedom 7 as part of Project Mercury. The farthest destination for a human spaceflight mission has been the Moon. Post-shuttle gap in United States human spaceflight capability
Overview – SpaceshipsSpaceShipTwo SpaceShipTwo uses all the same basic technology, carbon composite construction and design as SpaceShipOne. However it is around twice as large as that vehicle and will carry six passengers and two pilots. It is 60ft long with a 90" diameter cabin which is similar in size to a Falcon 900 executive jet albeit with no floor dissecting the cabin allowing maximum room for the astronauts to float in zero gravity. Each passenger gets the same seating position with two large windows: one side window and one overhead, so that, if you don't want to float free in space, and you'd rather just remain in your seat, you still get a great chance to see the view. No more squabbling over who has the best seat! The View Your views of earth will be maximised by large windows. The spaceship can be thought of as an air launched glider with a rocket motor and a couple of extra systems for spaceflight. SS1 photographed by Ron Dantowitz The spaceship is powered by a hybrid rocket motor. Back to top