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Everything would be lighter if Newton had not invented gravity.
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Gravity should not be taken lightly.
... such stuff as dreams are made on
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But that was not Newton who said that. It was Einstein.
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You need to come back down to earth.
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Munchies_Matt wrote: It is wind resistance that is the problem
So why doesn't NASA just launch rockets on still days?
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Or vacuum them before the launch
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Er, do you know what the escape velocity is, the direction of travel, and what the average wind vector on planet earth?
Now compare them.
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Munchies_Matt wrote: velocity
Munchies_Matt wrote: wind vector
Munchies_Matt wrote: direction of travel And that's the way the Falcon made the Kessel run in less than 12 parsecs.
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CodeWraith wrote: less than 12 parsecs
It needs to be fast as there aren't any toilets on board. Weirdly enough no spaceships in Star Wars seem to have any conveniences..
Now is it bad enough that you let somebody else kick your butts without you trying to do it to each other? Now if we're all talking about the same man, and I think we are... it appears he's got a rather growing collection of our bikes.
modified 31-Aug-21 21:01pm.
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And since a parallax second (parsec) is a unit of length (and not of time), it must be defined as the distance to the nearest toilet.
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Escape velocity[^]
Putting all the pedantism aside, still marvelous achievements.
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R. Giskard Reventlov wrote: Putting all the pedantism pedantry aside,
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18,000 mph if memory serves me correctly. Puts a bit of wind into perspective eh?
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Escape velocity at the Earth's surface is about 11.2 km/sec, which is 40,320 km/hr, which is 25,200 mph.
If you have an important point to make, don't try to be subtle or clever. Use a pile driver. Hit the point once. Then come back and hit it again. Then hit it a third time - a tremendous whack.
--Winston Churchill
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I agree that the actual delta-v produced by any practical rocket that reaches escape velocity must be higher than 11.2 km/sec. This is because (a) the acceleration profile is not a step function, and (b) using the highest acceleration that the astronauts were capable of enduring would result in the spacecraft overheating because of air resistance (those pesky Engineering considerations... ).
This, however, that does not change the fact that the escape velocity at the Earth's surface is approximately 11.2 km/sec. This gives the absolute lower bound on the delta-v that must be given to an object that is to escape the Earth's gravity.
If you have an important point to make, don't try to be subtle or clever. Use a pile driver. Hit the point once. Then come back and hit it again. Then hit it a third time - a tremendous whack.
--Winston Churchill
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And plenty of cogent reasons why it would be better to build and launch ships from orbit or a body with a lower escape velocity requirement (putting to one side the practicalities of setting that all up in the first place - nice to dream).
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Just do it when there is no wind. Can't believe NASA hasn't thought of this.
Oh wait....maybe it's air resistance that's the problem, not wind resistance...
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No, that's a X-15 covered with ablative heat protection, most probably before the flight.
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air+velocity=wind
HOw fast is a rocket going?
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Munchies_Matt wrote: air+velocity=wind
It's wind if it's the *air* that has velocity, not an object moving through it.
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I see, this is your deffinition of wind is it?
What do you call a windscreen then?
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