Why do so few people seem to realize that "escape velocity" is relevant only for unpowered objects and vehicles?

?2019-07-26T19:54:07Z

You seem to be mistaken
Unpowered Vehicles have a propensity to not move
The Escape Velocity for Earthbound Vehicles is 17, 500 mph
That would get the Vessel into Orbit
You would be doing well to throw something that hard !!
For Trans Lunar Injection it is 25, 000 mph
For crossing the Solar System, the Minimum is 35, 000 mph
The clue is in the word Velocity

?2019-07-22T09:49:05Z

Because that isn't true. Why do you think it is?

Jeffrey K2019-07-21T01:47:24Z

Most people don't even have any idea what escape velocity means.
You are right. A powered rocket can leave earth's gravity going at any speed. Nasa chooses a flight path that uses the least fuel.

billrussell422019-07-20T21:57:32Z

you have a point. With an infinite amount of power, a spaceship could boost at 100 MPH straight up and escape the planet easily.

However, at the point where the ship shuts off it's power, it has to have escape velocity for it's altitude or it will fall back.

But I disagree with the "so few people" part....

Raymond2019-07-20T21:48:08Z

Escape velocity is relevant to powered vehicles, to unpowered vehicles, to objects thrown out by accidents, etc.
Escape velocity does not care.

As you move away from a centre of gravity, the escape velocity relative to that object gets lower. Therefore, it is possible to power yourself at slow speed to a greater distance (where escape speed is lower), and then accelerate to that escape speed. You must still reach that escape speed if you want to escape.

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