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Astronomy/Earth's escape velocity

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Expert: Jayendra Upadhye - 4/3/2005


Question
What velocity is required for an object to leave the Earth and enter (land on) the Moon?

Answer
Hi,
The earth's escape velocity is 11 km / sec approx.
to be exact,
The minimum velocity that a body requires to permanently escape from a primary body. The escape velocity for the Earth is 11.2 km/sec and is the same for a molecule of hydrogen or a space ship. The escape velocity from the Sun is 618 km/sec; to escape from the Solar System at 1 AU, one needs a velocity of 49 km/sec. Mathematically, the velocity of escape is given by
Ve = (2GM/R)1/2
where G is the universal gravitational constant, M is the mass of the parent body, and R is the distance between the parent and escaping body.
ref:- http://www.mira.org/fts0/glossx.htm (look up escape velocity on that page).
Jayen

Astronomy

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Jayendra Upadhye

Expertise

1 - General questions on most astronomy topics such as:- Solar system, Cosmology, Black holes, Quasars, Dark matter etc. 2 - General questions about the geologies of planets. 3 - General questions about Orbits and laws governing them. 4 - General questions about rockets / spaceships 5 - General questions about stellar interiors and supernovas.

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I was an askme.com expert rated no#1 for quite some time - and was top ten there by the time it closed - in Astronomy and general science categories.

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Bachelor of Engg. (Electrical engg), Maharaja Sayajirao university of Baroda, Gujarat, India.

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None to write about except the askme rating if it is any worth!

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