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Online Rama Set

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There is no winners or losers and I can respect that you are willing to change your mind on things, that is very admirable. Continue to remain skeptical and agnostic and to learn as much as you can. This is a great website for expanding your mind.

Your two points of clarification are correct. Specifically on point 2, as the thrust produced by a rocket increases, the drag from the atmosphere will increase as well.
Technically the explanation for why the sun sets at higher altitudes is also "waves," and whatnot.

The SR71 has thermal expansion problems because it is in the atmosphere. In space, you no longer have such problems from friction in the atmosphere, but you have other problems to solve like dealing with solar radiation/darkness cycles (if you are in orbit).

If you watch the launch video (start at about 21:30), it has a little speed indicator in the upper right corner starting at T-4 seconds. The counter just steadily increases while the rockets are burning. When the rockets shut down, it stops accelerating or even slows down until the next rocket kicks in.


The rate at which the rocket accelerates is quite often about the rate at which a motorcycle or sportscar accelerates. On the speed indicator, 100km/h is about 60 mph, and often you will see between 2-4 seconds for the number to increase by 100. At one point it is accelerating much faster than that - when it is high, out of the atmosphere, but still being driven by the main booster, it's got a lot of power and no air to slow it down. Once it's in space, there's no hurry - the big hurry on launch is to get out of the atmosphere that steals energy through friction. This is why the second stage only has one engine - they can just burn it longer.

During the launch, you can see on the timeline (and hear announcements about) Max-Q - that's maximum dynamic pressure, right when it goes supersonic. The vehicle is going faster and faster, and higher and higher, and so at some point you get the maximum wind resistance. Higher than that, and the thinner air resists less. Lower than that, and you're going slow enough to have lower wind resistance.

Many rockets, including Falcon Heavy, do not operate at full throttle the entire time - it would be possible for you to exceed the structural strength of the rocket if you go too fast at too low an altitude. So, that's why you hear the announcers talking about throttling down and throttling up. They throttle down before Max-Q, then after it they throttle back up.

Does any of that help? If you have any questions about the launch I can try to answer them.

You do realize that the atmosphere does pose a problem for rockets right? They go at full throttle simply to escape Earth's gravity as quickly as possible (imagine if a rocket burned with just enough thrust to keep it hovering; it would be 0% efficient). The Space Shuttle goes at about 300 m / s halfway to max Q. However, because the atmosphere rapidly gets thinner, once a rocket clears the troposphere, it's pretty much okay.

The 17500 mi / h figure comes from the speed relative to the ground observer to stay in orbit. There is virtually no air/drag there (okay, for long periods of time, it isn't negligible and may require orbital stationkeeping, but for launches it's fine). It's perfectly reasonable that something can travel that quickly; this is basic conservation of momentum.

With so many people calling me ignorant, I suppose I will have to admit defeat.

It's not about winning and losing but your posts do show a lot of ignorance about how rockets work.
I really don't mean that as an insult, I don't know what you do in life but unless you work for SpaceX or NASA why would you know how rockets work?
I do at a very high level because I'm interested in science so watch the right documentaries or read the right books to get some high level understanding but there is absolutely nothing wrong with ignorance, there are loads of things I know next to nothing about.
Your only mistake is to argue from a position of ignorance "I don't understand how this works, therefore it can't".
As I and others have suggested, just do a bit of research about it. You seem willing to learn and engage honestly in debate which is a very good thing - very rare on here, most people are so set in their belief of a flat earth they won't even engage. You are asking the right questions and that is a good start.


"This is literally just a few people talking about it for a brief time every day on their spare time. That’s the flat earth movement" - Tom Bishop

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Online Tumeni

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Perhaps the Original Poster could outline the 'things' that he/she considers would actually PREVENT a rocket from achieving those speeds?

We can discount air resistance, maximum RPM for mechanicals, and such, so ... what? 
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Pete Svarrior "We are not here to directly persuade anyone ... You mistake our lack of interest in you for our absence."

Tom Bishop "We are extremely popular and the entire world wants to talk to us. We have better things to do with our lives than have in depth discussions with every single curious person. You are lucky to get one sentence dismissals from us"


That isn’t how the world works unfortunately. There are lots of places to go research rocket technology and it appears you should. You should probably also adopt an agnostic position until you have a really solid ground not to. So far it appears that you don’t accept this claim solely on the basis that it sounds outlandish and that is a terrible basis.

Another one who agrees that the rocket travels 86 football field lengths in one second. Thank's for your input. Agree to disagree.

So you will not talk about this with anyone who disagrees with you?

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Offline nickrulercreator

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2. The atmosphere has essentially no effect on the amount of thrust. Whether in atmosphere, or in a total vacuum, the same level of thrust can be achieved.

Am I getting this correct?

No. It's incorrect due to the Specific Thrust equation: https://www.grc.nasa.gov/www/k-12/VirtualAero/BottleRocket/airplane/specth.html

Rocket thrust is given by the equation F=(m')(ve)-(m0)(v0)+(Ae)(P1−P2) where (m') is the mass flow rate, (ve) is the average exit flow velocity across the exit plane, (m0) is the free stream mass flow rate, (v0) is the free stream velocity, (Ae) is the cross-sectional area of the exhaust jet at the exit plane, (P1) is the static pressure inside the engine just before the exit plane, and (P2) is the ambient static pressure (i.e. atmospheric pressure). If the ambient static pressure is a vacuum, meaning it is 0 (well, pretty close to 0), you have more total pressure (p1-0 is greater than p1-p2 if p2 is >0).
This end should point toward the ground if you want to go to space. If it starts pointing toward space you are having a bad problem and you will not go to space today.

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Offline Buran

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I think OP needs to ask himself what the max speed of a rocket could be if it were allowed to burn in a vacuum for as long as he wanted. It's my understanding that you could eventually reach light speed if given enough time. 86 football fields a second does sound insanely fast, but what part of physics says it's impossible? What says you cant go much faster?
Nicole, show me schematics for "Flat Earth."

You can’t even imagine how happy I am to have read this today! This is truly amazing - this is the first time I am seeing a flat-earther display open-mindedness and willingness to learn!!! In fact, this is by far the best thing I’ve read on this site so far. Thank you so much! Ladies and gentlemen, please, let’s celebrate this wonderful moment. I am completely serious by the way.


1. I've learned that air slows the rocket a lot. It can only reach 3,000 mph in atmosphere, but 18,000 mph at the edge of space. That increase is due to the lack of air resistance.

2. The atmosphere has essentially no effect on the amount of thrust. Whether in atmosphere, or in a total vacuum, the same level of thrust can be achieved.

Am I getting this correct? Any more information or corrections is greatly appreciated. Again, thank you for input, and allowing me to express my opinions on this matter.

You can’t even imagine how happy I am to have read this today! This is truly amazing - this is the first time I am seeing a flat-earther display open-mindedness and willingness to learn!!! In fact, this is by far the best thing I’ve read on this site so far. Thank you so much! Ladies and gentlemen, please, let’s celebrate this wonderful moment. I am completely serious by the way.


1. I've learned that air slows the rocket a lot. It can only reach 3,000 mph in atmosphere, but 18,000 mph at the edge of space. That increase is due to the lack of air resistance.

2. The atmosphere has essentially no effect on the amount of thrust. Whether in atmosphere, or in a total vacuum, the same level of thrust can be achieved.

Am I getting this correct? Any more information or corrections is greatly appreciated. Again, thank you for input, and allowing me to express my opinions on this matter.

Duly noted and celebrated.

Where have you looked for further information?

One thing I looked at was how fast the fastest jet plane can reach. It seems to be the SR71 at a approx 3540 km/h (2199.654 mph). According to what I read, at this speed the thermal expansion starts to pull the plane apart. That's extremely fast. For reference, a bullet averages at 1,700 mph.

So when I'm told that the Falcon Heavy can travel 17, 500 mph, or about 86 football field lengths in one second, I'm very skeptical about that claim.
And for good reason too ! There has been (nor will there be) any verifiable documented footage of a man made object traveling at 17, 500 mph.

Where have you looked for further information?

One thing I looked at was how fast the fastest jet plane can reach. It seems to be the SR71 at a approx 3540 km/h (2199.654 mph). According to what I read, at this speed the thermal expansion starts to pull the plane apart. That's extremely fast. For reference, a bullet averages at 1,700 mph.

So when I'm told that the Falcon Heavy can travel 17, 500 mph, or about 86 football field lengths in one second, I'm very skeptical about that claim.
And for good reason too ! There has been (nor will there be) any verifiable documented footage of a man made object traveling at 17, 500 mph.
So we're going to casually ignore all video of the ISS then? Cool. Go take some images yourself. Make sure to use a decent camera so you can see it's clearly man made. Calculate it's speed based on time it takes to travel across the sky. Feel free to pick any altitude you want to pretend it's at. Report back to us how fast it's going. Genuinely curious, since I believe you've said it's being carried by a balloon? Or am I mixing you up with someone else?

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Offline nickrulercreator

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And for good reason too ! There has been (nor will there be) any verifiable documented footage of a man made object traveling at 17, 500 mph.

What a preposterously ignorant claim. Go ahead and ignore all of the independent observations of satellites orbiting Earth I guess. Oh wait, you've stated before they're fake, claiming they're just planes, without providing a shred of evidence.
This end should point toward the ground if you want to go to space. If it starts pointing toward space you are having a bad problem and you will not go to space today.

So we're going to casually ignore all video of the ISS then? Cool. Go take some images yourself. Make sure to use a decent camera so you can see it's clearly man made. Calculate it's speed based on time it takes to travel across the sky. Feel free to pick any altitude you want to pretend it's at. Report back to us how fast it's going. Genuinely curious, since I believe you've said it's being carried by a balloon? Or am I mixing you up with someone else?
And for good reason too ! There has been (nor will there be) any verifiable documented footage of a man made object traveling at 17, 500 mph.
What a preposterously ignorant claim. Go ahead and ignore all of the independent observations of satellites orbiting Earth I guess. Oh wait, you've stated before they're fake, claiming they're just planes, without providing a shred of evidence.
Go ahead and slap whatever video you have of anything traveling at 17,500 mph.

Look at it...Let all of us look at it and see if there is anyway possible of accurately verifying the speed of the object from the video...

LOL!!!
« Last Edit: February 13, 2018, 09:02:34 PM by totallackey »

So we're going to casually ignore all video of the ISS then? Cool. Go take some images yourself. Make sure to use a decent camera so you can see it's clearly man made. Calculate it's speed based on time it takes to travel across the sky. Feel free to pick any altitude you want to pretend it's at. Report back to us how fast it's going. Genuinely curious, since I believe you've said it's being carried by a balloon? Or am I mixing you up with someone else?
And for good reason too ! There has been (nor will there be) any verifiable documented footage of a man made object traveling at 17, 500 mph.
What a preposterously ignorant claim. Go ahead and ignore all of the independent observations of satellites orbiting Earth I guess. Oh wait, you've stated before they're fake, claiming they're just planes, without providing a shred of evidence.
Go ahead and slap whatever video you have of anything traveling at 17,500 mph.

Look at it...Let all of us look at it and see if there is anyway possible of accurately verifying the spped of the object from the video...

LOL!!!
Not attempting to claim I'm positive it will come out to that speed. I'm telling you to go and perform an experiment for yourself. Find a time you can watch the ISS going over. Grab a camera. Run some data. See how high up it is/should be and how fast that means it's going based on that information. Since I'm almost positive even if I did all of this for you, you would find some reason to not believe it. The information here can be used equally well against an object in the sky. Let's see what you come up with. Will it be less? More? I have no idea! That's what makes it fun! After you do it, the rest of us can repeat the experiment and see what we come up with, so make sure to list all of your variables so we can recreate things correctly!

Offline StinkyOne

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So we're going to casually ignore all video of the ISS then? Cool. Go take some images yourself. Make sure to use a decent camera so you can see it's clearly man made. Calculate it's speed based on time it takes to travel across the sky. Feel free to pick any altitude you want to pretend it's at. Report back to us how fast it's going. Genuinely curious, since I believe you've said it's being carried by a balloon? Or am I mixing you up with someone else?
And for good reason too ! There has been (nor will there be) any verifiable documented footage of a man made object traveling at 17, 500 mph.
What a preposterously ignorant claim. Go ahead and ignore all of the independent observations of satellites orbiting Earth I guess. Oh wait, you've stated before they're fake, claiming they're just planes, without providing a shred of evidence.
Go ahead and slap whatever video you have of anything traveling at 17,500 mph.

Look at it...Let all of us look at it and see if there is anyway possible of accurately verifying the spped of the object from the video...

LOL!!!

Why can't something travel 17500 mph? Your incredulity is not a reason.

Go to the site below, go to the tracker portion, find your location, go outside at the right time and look up. It is traveling at 7.7 KM per sec.
https://www.thehumanitystar.com/
I saw a video where a pilot was flying above the sun.
-Terry50

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Online Tumeni

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Go ahead and slap whatever video you have of anything traveling at 17,500 mph.

Look at it...Let all of us look at it and see if there is anyway possible of accurately verifying the spped of the object from the video...


Doesn't need to be video. I can go outside and watch the ISS for myself. I'm sure I could do the trig and arithmetic to calculate its speed for myself, but I really don't see any need to. I've seen primary school students do it, so why bother?

I suggest readers here take a look at planewavemedia. Their speciality is motorised tracking telescopes, as far as I can gather. Their YouTube site has a number of tracking videos, with their telescope switching from satellite to satellite. I'm sure they could do computations of, or already have, the data which will tell us how fast said satellites are moving.

On screen, you can see;
The telescope itself, moving back and forth
A star chart showing the area of sky it is looking at
The scrolling data that outlines what it's doing, and where it's pointing
The output from the telescope, showing the satellite it is tracking, along with the background starfields whizzing by


At least two independent telescope operators have tracked the SpaceX Tesla on its way to Mars or thereabouts. I haven't looked at their data in detail, but imagine that we could compute time taken against distance from Earth to derive its speed.
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Pete Svarrior "We are not here to directly persuade anyone ... You mistake our lack of interest in you for our absence."

Tom Bishop "We are extremely popular and the entire world wants to talk to us. We have better things to do with our lives than have in depth discussions with every single curious person. You are lucky to get one sentence dismissals from us"

Offline model 29

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So is ffps (football fields per second) an official measurement of speed now?

So we're going to casually ignore all video of the ISS then?
By no means will we ignore it. I welcome it. It clearly demonstrates that wherever this footage originates from, it is not depicting speeds attained in the 17, 500 MPH range.
Cool. Go take some images yourself. Make sure to use a decent camera so you can see it's clearly man made.
Nobody is denying that whatever we see when we look at what is called the ISS originates at the hands of humanity.
Calculate it's speed based on time it takes to travel across the sky. Feel free to pick any altitude you want to pretend it's at. Report back to us how fast it's going.
One more nail in the coffin as it is not traveling 17,500 MPH.
Genuinely curious, since I believe you've said it's being carried by a balloon? Or am I mixing you up with someone else?
Must be. I have never claimed that.

By no means will we ignore it. I welcome it. It clearly demonstrates that wherever this footage originates from, it is not depicting speeds attained in the 17, 500 MPH range.
What is your basis for that claim?
Someone above explained how you can calculate its velocity from observations. Here is another way:

"This is literally just a few people talking about it for a brief time every day on their spare time. That’s the flat earth movement" - Tom Bishop