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Hyperbolic geometry
In mathematics, hyperbolic geometry is a non-Euclidean geometry, meaning that the parallel postulate of Euclidean geometry is rejected. The parallel postulate in Euclidean geometry states, for two ... > more -
Solar wind
A solar wind is a stream of charged particles (i.e., a plasma) which are ejected from the upper atmosphere of a star. When originating from stars other than the Earth's Sun, it is sometimes called a ... > more -
Rocket engine
A rocket engine is a reaction engine that can be used for spacecraft propulsion as well as terrestrial uses, such as missiles. Rocket engines take their reaction mass from within the vehicle and form ... > more -
Alpha Centauri
Alpha Centauri (α Cen / α Centauri) is the brightest star system (a triple star system) in the southern constellation of Centaurus, and contains the fourth brightest star in the night ... > more -
Voyager program
The Voyager program consisted of a pair of unmanned scientific probes, Voyager 1 and Voyager 2, launched in 1977. They were sent to study Jupiter and Saturn, using an advantageous planetary alignment ... > more -
Scaled Composites SpaceShipOne
The Scaled Composites Model 316 SpaceShipOne is an experimental air-launched suborbital spaceplane that uses a hybrid rocket motor. The design features a unique "shuttlecock" reentry system whose ... > more -
Solid-fuel rocket
A solid rocket or a solid fuel rocket is a rocket with a motor that uses solid propellants (fuel/oxidizer). The earliest rockets were solid fuelled, powered by gunpowder, used by the Chinese in ... > more -
Space elevator
A space elevator is a theoretical structure designed to transport material from a planet's surface into space. Many different types of space elevators have been proposed. They all share the goal of ... > more
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