If so called gravity is weaker...

If so called gravity is weaker the higher you go, then why do so called space craft need to reach an escape velocity to get into so called space?

If so called gravity is weaker the higher you go, then why do so called space craft need to reach an escape velocity to get into so called space?

I gotta say I don't really understand your question?

Quote from: sceptimatic on December 24, 2013, 06:15:42 AM

If so called gravity is weaker the higher you go, then why do so called space craft need to reach an escape velocity to get into so called space?

I gotta say I don't really understand your question?

Well let's put it this way. If gravity is weaker the higher you go up, then why does a so called space rocket need to achieve an escape velocity to get into space. What is stopping it just going into space at (for instance) 500 mph or less or whatever. Why 25,000 mph or so?
It's not like so called gravity is getting stronger, is it.

Quote from: Spank86 on December 24, 2013, 06:42:54 AM

Quote from: sceptimatic on December 24, 2013, 06:15:42 AM

If so called gravity is weaker the higher you go, then why do so called space craft need to reach an escape velocity to get into so called space?

I gotta say I don't really understand your question?

Well let's put it this way. If gravity is weaker the higher you go up, then why does a so called space rocket need to achieve an escape velocity to get into space. What is stopping it just going into space at (for instance) 500 mph or less or whatever. Why 25,000 mph or so?
It's not like so called gravity is getting stronger, is it.

Well I'm no rocket scientist but I'd hazard a guess that the answer is in part to do with the time it would take (probably the least part), in part to do with the lower pressures up meaning that the thrust from the rockets provides less propulsion (akin to pushing off against a wall or a sheet), and the need to achieve a decent velocity to orbit or to match orbit with whatever they are going up there for.

 But that's really just a guess while someone more informed gets here.

If so called gravity is weaker the higher you go, then why do so called space craft need to reach an escape velocity to get into so called space?

Because it's only slightly weaker at orbital altitude.  90% from what I've read.

in part to do with the lower pressures up meaning that the thrust from the rockets provides less propulsion (akin to pushing off against a wall or a sheet),

Actually they don't rely on pushing off the outside air.  It's the unequal pressure inside the combustion chamber and expanding exiting pressure/exhaust within the nozzle.

I am merely clearing up a small point however, and do not wish to derail the topic, hence I shall refrain from discussing this further in this thread.  I apologize to everyone in advance if this turns into yet another 80 page debate with scepti about how rockets work.

If you could maintain 1MPH long enough, you could still get into space, but that's not what escape velocity relates to. Maintaining that 1MPH relies on continuous thrust, whereas escape velocity is actually the velocity required to escape the gravity well of an object (for the purpose of this discussion, that object is the earth) without any thrust being applied after that velocity is reached. Did you follow that? I'll try a different wording just in case: if I fired an object from a gun that was mounted vertically on the surface of the earth, it is not being propelled by anything once it leaves the barrel. If it leaves that barrel at any speed less than escape velocity, it will always fall back to earth. If it leaves the barrel at a speed equal to or greater than escape velocity, it will never fall back to earth.

The reason this works is that gravity becomes weaker the further away you get. Think of it like coasting up a hill that rounds off toward the top until it levels out completely. If you hit the bottom at a high enough speed, you'll get all the way to the top without having to add any extra power. If you hit the bottom going too slow, you either won't make the top of the hill, or you will have to add power to get there.

Got it now? Or have I wasted my time?

EDIT: I tell you what, let me Google that for you.

Gravity Doesn't actually exist but yea Earth at 22,236 Miles Altitude is 0 Degrees Equilibrium Say Sea level is 133 Degrees.

Therefore at 11,168 you are at  33.25 Degrees

At 5,584 you are at 66.5 Degrees.

And so on and so forth. After 22,236 Miles it get's rather loopy.

22,236 - 0D
44,476 - 1D
88944 - 2D
177888 - 4D
266832 - 6D
355776 - 8D
1423104 - 32D
5692416 - 128D
11384832 - 256D
17788800 - 400D
71155200 - 800D
284620800 - 1200D
1138483200 -1600D (Universe Ends, Divide by 2 to get linear Universe of 569,241,600 Miles)

Remember compression layouts. (You get progressively smaller the further you go)

1:4 =.25
2:16 =.125
3:64 =.046875
4:256 =.015625
5:1024 = .0048828125
6:4096 = .00146484375
7:16384 = 0.00042724609375

Gravity Doesn't actually exist but yea Earth at 22,236 Miles Altitude is 0 Degrees Equilibrium Say Sea level is 133 Degrees.

Therefore at 11,168 you are at  33.25 Degrees

At 5,584 you are at 66.5 Degrees.

Yes; gravity definitely does exist—which is why you're not flung off the planet.

And I have absolutely no idea what this is all about:

"Earth at 22,236 Miles Altitude is 0 Degrees Equilibrium Say Sea level is 133 Degrees."

Please clarify your terminology.

Please just take an introductory physics class at a local community college.  The fact that you asked this question in the first place means you cannot possibly understand the answer until you have the sufficient mathematical background.

Unless you think math is part of the conspiracy too, in which case, just forget it.

Well let's put it this way. If gravity is weaker the higher you go up, then why does a so called space rocket need to achieve an escape velocity to get into space. What is stopping it just going into space at (for instance) 500 mph or less or whatever. Why 25,000 mph or so?

This question indicates two things to me.  Firstly, you have very little understanding of gravitational theory.

Secondly, you also have very little understanding of jet propulsion.  A rocket moving out of the earth's gravity field does not necessarily need to attain escape velocity to do so, but (as you suggest) could achieve the same result at any speed  AND sufficient fuel.   The fuel is the issue.

Please just take an introductory physics class at a local community college.  The fact that you asked this question in the first place means you cannot possibly understand the answer until you have the sufficient mathematical background.

Unless you think math is part of the conspiracy too, in which case, just forget it.

Go and take a long walk off a short pier you waste of space.

Quote from: sceptimatic on December 24, 2013, 06:49:36 AM

Well let's put it this way. If gravity is weaker the higher you go up, then why does a so called space rocket need to achieve an escape velocity to get into space. What is stopping it just going into space at (for instance) 500 mph or less or whatever. Why 25,000 mph or so?

This question indicates two things to me.  Firstly, you have very little understanding of gravitational theory.

Secondly, you also have very little understanding of jet propulsion.  A rocket moving out of the earth's gravity field does not necessarily need to attain escape velocity to do so, but (as you suggest) could achieve the same result at any speed  AND sufficient fuel.   The fuel is the issue.

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

Is there any particular reason as to why you're so consistently angry?  A lack of self esteem?  An inferiority complex maybe?  Or do you just hate the entire human population for no particular reason.

What a dismal, everyday life you must lead.  Constantly at war with the world.

Quote from: sceptimatic on December 28, 2013, 09:09:47 AM

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

Is there any particular reason as to why you're so consistently angry?  A lack of self esteem?  An inferiority complex maybe?  Or do you just hate the entire human population for no particular reason.

What a dismal, everyday life you must lead.  Constantly at war with the world.

Oh, you shouldn't try and read into the mind behind the typing, kid. It's just my way of telling kids like you that you are full of horse crap aided by  books of fiction that you try and pass off as fact.
You see, it doesn't work with me and I call you a clown...not in anger but in truth, because that's what you are...you are another circus clown that's came to town and like others before you, you either open your mind or keep it closed and wither away.

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

He would appear to be right in that "escape velocity" seems to refer to ballistic objects not self propelled ones.

Quote from: sceptimatic on December 28, 2013, 09:09:47 AM

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

He would appear to be right in that "escape velocity" seems to refer to ballistic objects not self propelled ones.

Then explain why escape velocity is 25,000 mph then.

Quote from: Spank86 on December 28, 2013, 09:30:48 AM

Quote from: sceptimatic on December 28, 2013, 09:09:47 AM

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

He would appear to be right in that "escape velocity" seems to refer to ballistic objects not self propelled ones.

Then explain why escape velocity is 25,000 mph then.

Because that's the speed they say you would need to accelerate something to for it to leave the earths atmosphere (from ground level) with no extra propulsion?

Then explain why escape velocity is 25,000 mph then.

As I've already attempted to explain, escape velocity is a function of time, fuel usage, and mass.  It's not calculated to overcome the earth's gravity field solely.  A rocket could never carry a sufficient fuel load to attain orbit at (say) 500 mph velocity.  Hence the extreme acceleration.

Quote from: sceptimatic on December 28, 2013, 09:32:23 AM

Quote from: Spank86 on December 28, 2013, 09:30:48 AM

Quote from: sceptimatic on December 28, 2013, 09:09:47 AM

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

He would appear to be right in that "escape velocity" seems to refer to ballistic objects not self propelled ones.

Then explain why escape velocity is 25,000 mph then.

Because that's the speed they say you would need to accelerate something to for it to leave the earths atmosphere (from ground level) with no extra propulsion?

That makes no sense at all. I'm sure you know this.

Quote from: sceptimatic on December 28, 2013, 09:32:23 AM

Then explain why escape velocity is 25,000 mph then.

As I've already attempted to explain, escape velocity is a function of time, fuel usage, and mass.  It's not calculated to overcome the earth's gravity field solely.  A rocket could never carry a sufficient fuel load to attain orbit at (say) 500 mph velocity.  Hence the extreme acceleration.

Makes no sense at all and you know it.

Quote from: Spank86 on December 28, 2013, 09:36:55 AM

Quote from: sceptimatic on December 28, 2013, 09:32:23 AM

Quote from: Spank86 on December 28, 2013, 09:30:48 AM

Quote from: sceptimatic on December 28, 2013, 09:09:47 AM

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

He would appear to be right in that "escape velocity" seems to refer to ballistic objects not self propelled ones.

Then explain why escape velocity is 25,000 mph then.

Because that's the speed they say you would need to accelerate something to for it to leave the earths atmosphere (from ground level) with no extra propulsion?

That makes no sense at all. I'm sure you know this.

which bit was it you got lost at?

Escape velocity is the name given to the speed that something needs to be initially traveling at for it to escape the gravitational pull of (in this case) the earth assuming no means of propulsion after attaining this velocity.

So it applies to ballistic objects, for example a cannonball (fired up to speed then no more thrust applied along it's path).

Quote from: sceptimatic on December 28, 2013, 09:42:03 AM

Quote from: Spank86 on December 28, 2013, 09:36:55 AM

Quote from: sceptimatic on December 28, 2013, 09:32:23 AM

Quote from: Spank86 on December 28, 2013, 09:30:48 AM

Quote from: sceptimatic on December 28, 2013, 09:09:47 AM

Like I told you in the other thread. You are nothing but a clown. Devoid of your own thoughts. Go and follow your masters.

He would appear to be right in that "escape velocity" seems to refer to ballistic objects not self propelled ones.

Then explain why escape velocity is 25,000 mph then.

Because that's the speed they say you would need to accelerate something to for it to leave the earths atmosphere (from ground level) with no extra propulsion?

That makes no sense at all. I'm sure you know this.

which bit was it you got lost at?

Escape velocity is the name given to the speed that something needs to be initially traveling at for it to escape the gravitational pull of (in this case) the earth assuming no means of propulsion after attaining this velocity.

So it applies to ballistic objects, for example a cannonball (fired up to speed then no more thrust applied along it's path).

I'm certainly not lost. It's you lot that are lost.

I'm certainly not lost. It's you lot that are lost.

So are you saying you understand the concept but reject the premise behind it?

Because that's fine we know that already, it only makes me wonder why you bring it up. Why question parts of a system when you just reject it flat out. The only point of questioning is if you want to find holes in the system.


Essentially you've got your answer that in this model a rocket doesn't NEED to achieve escape velocity to leave the atmosphere, only ballistic objects need to do that.

Quote from: sceptimatic on December 28, 2013, 09:51:20 AM

I'm certainly not lost. It's you lot that are lost.

So are you saying you understand the concept but reject the premise behind it?

Because that's fine we know that already, it only makes me wonder why you bring it up. Why question parts of a system when you just reject it flat out. The only point of questioning is if you want to find holes in the system.


Essentially you've got your answer that in this model a rocket doesn't NEED to achieve escape velocity to leave the atmosphere, only ballistic objects need to do that.

And which ballistic object do you know that's escaped the atmosphere?
Do you people actually have this stuff IMPLANTED into your minds from birth from a chip or something?
Surely you can't read up on it and just accept it all, there must be drugs involved in some fashion, or like I said, some kind of micro chip implanted into your skull that interferes with your brains ability to use rational thought.

And which ballistic object do you know that's escaped the atmosphere?
Do you people actually have this stuff IMPLANTED into your minds from birth from a chip or something?

It's a theoretical number. It's also based on something massless so any object would actually need to go a smidge faster.

I don't understand your problem with this. It's entirely consistent with the theory of gravity (which I already know you reject). Why are you surprised when someone who accepts gravity also accepts this number as being what would be needed to get a non self propelled object "into space"?

The number works, the maths work (what I understand of them). you simply reject the basic idea behind it all so I ask again, why bother questioning the intricacies and calculations if you reject the initial premise? It's a waste of time if that's your fallback each time it's explained. You might as well reject in ignorance or indeed simply google your questions since all the information's out there as to what the conspiracy wants you to believe.

Surely you can't read up on it and just accept it all, there must be drugs involved in some fashion, or like I said, some kind of micro chip implanted into your skull that interferes with your brains ability to use rational thought.

I find your theories on the subject just as irrational as the whole round earth idea, the difference is the round earth explains things in a logical and coherent way and provides theories which can be tested. your Ideas do not. I have yet to hear you speak of a single way your ideas could be verified or disproved.

Makes no sense at all and you know it.

Remember that truth is stranger than fiction because fiction has to make sense.

Quote from: sceptimatic on December 28, 2013, 09:44:38 AM

Makes no sense at all and you know it.

Remember that truth is stranger than fiction because fiction has to make sense.

No, you are wrong. Fiction does not have to make any sense whatsoever. The global earth model is testament to that.

If so called gravity is weaker the higher you go, then why do so called space craft need to reach an escape velocity to get into so called space?

Okay, again but simplified:
- escape velocity is not required to achieve space flight, any velocity will do so long as it can be maintained long enough.
- escape velocity is the velocity required for a ballistic object to never return to earth. ie, after it's initial burst of thrust, it can coast forever and never fall back.

It is believed by some that the first man-made object to achieve this speed was a vent-shaft cover at a nuclear test site. Having accidentally been left in place covering a vent shaft, it was blown off the mouth of the shaft when the test bomb was detonated, achieving escape velocity in the process.
NOTE: this story has proven difficult to verify, so may just be a story. Still, it's a good one!

Quote from: sceptimatic on December 24, 2013, 06:15:42 AM

If so called gravity is weaker the higher you go, then why do so called space craft need to reach an escape velocity to get into so called space?

Okay, again but simplified:
- escape velocity is not required to achieve space flight, any velocity will do so long as it can be maintained long enough.
- escape velocity is the velocity required for a ballistic object to never return to earth. ie, after it's initial burst of thrust, it can coast forever and never fall back.

It is believed by some that the first man-made object to achieve this speed was a vent-shaft cover at a nuclear test site. Having accidentally been left in place covering a vent shaft, it was blown off the mouth of the shaft when the test bomb was detonated, achieving escape velocity in the process.
NOTE: this story has proven difficult to verify, so may just be a story. Still, it's a good one!

Ok, so let's get this straight. If and I mean IF I could float up into the sky at 1 mph, I can float straight through the atmosphere into space at 1 mph. Is this what you are saying?

Also, if you believe that story about the vent cover then you need treatment.

Ok, so let's get this straight. If and I mean IF I could float up into the sky at 1 mph, I can float straight through the atmosphere into space at 1 mph. Is this what you are saying?

Yes. If you can maintain any speed, it will get you there eventually.

Also, if you believe that story about the vent cover then you need treatment.

I did say "believed by some", not "I believe".

So, setting aside your own beliefs for just a moment, and speaking in terms of RE science, do you understand the concept of escape velocity, and why it is not required for general space flight?