escape velocity


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Related to escape velocity: orbital velocity

escape velocity,

the velocity a body must be given in order to escape the gravitational hold of some other larger body, e.g., the earth, moon, or sun. A body given less than the escape velocity will fall back toward the surface of the larger body; a body given a velocity equal to or greater than the escape velocity will still be attracted by the larger body, but this force will not be sufficient to cause it to return. Escape velocity depends on the mass of the larger body and the distance of the smaller body from its center, being proportional to the square root of the ratio of these two quantities. The velocity of escape from the earth at its surface is about 7 mi (11.3 km) per sec, or 25,000 mi per hr; from the moon's surface it is 1.5 mi (2.4 km) per sec; and for a body at the earth's distance from the sun to escape from the sun's gravitation, the velocity must be 26 mi (41 km) per sec.

escape velocity

The minimum velocity required for an object to enter a parabolic trajectory around a massive body and hence escape from its vicinity. The object will keep moving away from the body although it travels at decreasingly lower speeds as the massive body's gravitational attraction continues to slow it down. If the object does not attain escape velocity it will enter an elliptical orbit around the body. If escape velocity is exceeded the object will follow a hyperbolic path. The escape velocity at a distance r from the center of a massive body, mass m , is given by √(2Gm /r ), where G is the gravitational constant. The escape velocity from the Earth's surface is about 11.2 km s–1, from the Moon 2.4 km s–1, and from the Sun 617.7 km s–1. For a massive body to retain an atmosphere the average velocity of the gas molecules must be well below escape velocity.

escape velocity

[ə′skāp və‚läs·əd·ē]
(astronomy)
The minimum speed away from a parent body that a particle must acquire to escape permanently from the gravitational attraction of the parent.

escape velocity

the minimum velocity that a body must have in order to escape from the gravitational field of the earth or other celestial body
References in periodicals archive ?
Jules Verne's fictional mission to the moon used a land-based gun that propelled the space capsule to the Earth's escape velocity, which can be calculated to be seven miles per second, or 25,000 miles per hour.
current manuscript, Escape Velocity, are forthcoming in the Paris
EMC's new suite of storage software products, released on April 25, focuses on both markets with its Symmetrix and Clariion support (See "Will Escape Velocity Put EMC Storage In Orbit?
In many ways a darker sequel to Escape Velocity, which has become the definitive guide to the wired world, The Pyrotechnic Insanitarium is itself a rollercoaster ride through a lurid landscape fairly pulsing with schizodistractions and apocalyptic contraptions.
To examine these strengths and weaknesses more closely, we will examine subject access to Escape Velocity (Dery, 1996), a nonfiction work, in two contexts.
Jupiter and Saturn present particularly daunting prospects for exploitation, Lewis acknowledges, since their powerful gravitational fields would require any departing vehicle to have an extremely high escape velocity.
Had Dery been on his game, he might have realized that the seemingly idiotic question cut straight to the heart of Escape Velocity, his invaluable contribution to the ever-burgeoning cybercrit canon.
This escape velocity equals 7 miles per second for Earth but only 1.
The fact is, PIMs are beginning to look like a category that may never reach escape velocity.
When space dust particles collide with these elements in Earth's atmosphere, the crashes could give them "the necessary escape velocity and upward trajectory to escape Earth's gravity.
Dell Technologies Capital is comprised of a team of highly experienced investors with an extensive network of industry contacts to help our portfolio companies achieve escape velocity.