Space launch

of Artemis II. A space launch is the phase of a spaceflight mission during which a launch vehicle reaches space. The launch may be sub-orbital or the launch may continue until the vehicle reaches orbit. A space launch begins at a launch pad, which may be on land or at sea, or when the launch vehicle is released mid-air from an aircraft.

of Artemis II.]] A space launch is the phase of a spaceflight mission during which a launch vehicle reaches space. The launch may be sub-orbital or the launch may continue until the vehicle reaches orbit. A space launch begins at a launch pad, which may be on land or at sea, or when the launch vehicle is released mid-air from an aircraft. completed the first human private spaceflight in 2004, reaching an altitude of . |alt=A white rocketship with oddly-shaped wings at rest on a runway.]] There is no clear boundary between Earth's atmosphere and space, as the density of the atmosphere gradually decreases as the altitude increases. There are several standard boundary designations, namely: The has established the Kármán line at an altitude of as a working definition for the boundary between aeronautics and astronautics. This is used because at an altitude of about , as Theodore von Kármán calculated, a vehicle would have to travel faster than orbital velocity to derive sufficient aerodynamic lift from the atmosphere to support itself. Until 2021, the United States designated people who travel above an altitude of as astronauts. Astronaut wings are now only awarded to spacecraft crew members that "demonstrated activities during flight that were essential to public safety, or contributed to human space flight safety". NASA's Space Shuttle used , or , as its re-entry altitude (termed the Entry Interface), which roughly marks the boundary where atmospheric drag becomes noticeable, thus beginning the process of switching from steering with thrusters to maneuvering with aerodynamic control surfaces. In 2009, scientists reported detailed measurements with a Supra-Thermal Ion Imager (an instrument that measures the direction and speed of ions), which allowed them to establish a boundary at above Earth. The boundary represents the midpoint of a gradual transition over tens of kilometers from the relatively gentle winds of the Earth's atmosphere to the more violent flows of charged particles in space, which can reach speeds well over . W=mgh, m=1 kg, g=9.82 m/s 2 , h=10 5 m. W=1*9.82*10 5 ≈10 6 J/kg=1MJ/kg In practice, a higher energy than this is needed to be expended due to losses such as airdrag, propulsive efficiency, cycle efficiency of engines that are employed and gravity drag. In the past fifty years, spaceflight has usually meant remaining in space for a period of time, rather than going up and immediately falling back to earth. This entails orbit, which is mostly a matter of velocity, not altitude, although that does not mean air friction and relevant altitudes in relation to that, and orbit, do not need to be considered. At much higher altitudes than many orbital ones maintained by satellites, altitude begins to become a larger factor and speed a lesser one. At lower altitudes, due to the high speed required to remain in orbit, air friction is an important consideration affecting satellites, much more than in the popular image of space. At even lower altitudes, balloons, with no forward velocity, can serve many of the roles satellites play. ==Extraterrestrial== There have been some extraterrestrial sites of space launches. Mostly from the Moon, such as the first, by the Apollo program return launches from the respective moonbases. But also from asteroids. from the last Apollo lunar base at Taurus–Littrow (Apollo 17, 1972).]] LATEST SATELLITE LAUNCHES from http://www.n2yo.com/. The Space Review is an online publication devoted to in-depth articles, commentary, and reviews regarding all aspects of space exploration.

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