Astronomy/escape

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Expert: - 2/14/2004


Question
Does a heavier rocket need to reach a higher speed than a lighter rocket in order to escape from Earth?

Answer
James,
The weight, mass, volume, whatever....is unimportant....
The body in question simply has to achieve a velocity
of about 7 miles per second (25,200 mph) away from the
Earth to escape the Earth's gravitational well.

[Notice that going into orbit around the Earth does not
require escape velocity....here we need only 5 miles per
second (18,000 mph) to achieve orbital velocity....and again, the weight, size, mass, volume....is not important....only the velocities relative to the Earth.]

Naturally, in both cases, the more massive the body, the more fuel (energy) would be required to achieve both of
those velocities in question.

Hope this helps,
Clear Skies,
Tom Whiting
Erie, PA  

Astronomy

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Tom Whiting

Expertise

Astronomy has been my hobby/pasttime for over 50 years.  Currently own 3 telescopes, the largest of which is a 30 inch Newtonian truss Dob that is portable.I taught Astronomy/Meteorology at the University Level for 13 years before retiring in 1995. Being retired and home most of the time, I am able to answer all questions relatively quickly, unless it's a new moon weekend with good observing conditions.  No astrology questions please, or questions about alleged UFO picture identifications.

Experience

Experience: Astronomy has been my hobby and study for over 50 years. We currently now own a 30 inch portable telescope (Updated - Pennsylvania`s largest portable telescope). It can be seen on our website at:http://www.velocity.net/~bwhiting and also attend several regional starparties during the year, and have been on 5 total solar eclipse expeditions.

Organizations: President, Erie County Mobile Observers Group for over 15 years.

Publications: Wrote the "Over Erie Skies" newspaper article in our local newspaper for 11 years (1975-86).

Education: Masters Degree- Taught at the University level for 13 years. Retired 20 years -USAF Pilot - KC-135 with 180 combat missions;  Also Eagle Scout, Philmont staff 2 Yrs, Order of Arrow Lodge Chief, Ham Radio (inactive).

Awards: two discoveries: The mini-coathanger asterism in Ursa Minor (the little dipper) And the mini-ladle- another asterism in the bowl of Ursa Minor. Clients: Currently President of the ECMOG as mentioned above.

Education/Credentials
BS  Metallurgical Engineering Grove City College, PAMaster's Degree, Gannon University, Erie, PA Also retired USAF pilot, 20 years.

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