Space Tourism

Quote from:  Wikipedia

Some people (including the FAI in some of their publications) also use the expression "edge of space" to refer to a region below the conventional 100 km boundary to space, which is often meant to include substantially lower regions as well. Thus, certain balloon or airplane flights might be described as "reaching the edge of space". In such statements, "reaching the edge of space" merely refers to going higher than average aeronautical vehicles commonly would

Average aeronautical vehicles I assume include military aircraft around the world, many of which can reach 30-60,000 feet. That would make them average, as there are a lot of them. The concorde therefore falls in to this category.

EDIT: You say NASA is a fraud, yet you take figures used by NASA every single time they plan and perform missions. So please, explain to me again how NASA is wrong and their figures are wrong and how you use their figures to prove them wrong.

Space is defined as a lack of atmospheric density. 60,000 feet is near space because it is above 90% of the atmosphere.

The Kármán line lies at an altitude of 100 kilometres (62 mi) above the Earth's sea level, and is commonly used to define the boundary between the Earth's atmosphere and outer space.^[2]

Since NASA is a fraud, why should we care what they say about space?

Some people (including the FAI in some of their publications) also use the expression "edge of space" to refer to a region below the conventional 100 km boundary to space, which is often meant to include substantially lower regions as well.

Quote from: ThinkingMan on September 14, 2012, 08:37:29 AM

I would hardly call 60,000 feet the edge of space. That's less than 4 miles higher than a standard airliner's cruising altitude.

On Wikipedia we read that 90% of the atmosphere by mass is below an altitude of 16 km (53493 feet).

If the atmosphere is what blocks the Sun and causes night, and you are above 90% of the atmosphere at 60,000 feet wouldn't you be able to see the Sun 24 hours a day from that altitude?

Quote from: MrT on September 14, 2012, 11:59:17 AM

If the atmosphere is what blocks the Sun and causes night, and you are above 90% of the atmosphere at 60,000 feet wouldn't you be able to see the Sun 24 hours a day from that altitude?

Looking through 10% of atmosphere for tens of thousands of miles is still significant.

Quote from: ThinkingMan on September 14, 2012, 10:35:48 AM

Quote from:  Wikipedia

Some people (including the FAI in some of their publications) also use the expression "edge of space" to refer to a region below the conventional 100 km boundary to space, which is often meant to include substantially lower regions as well. Thus, certain balloon or airplane flights might be described as "reaching the edge of space". In such statements, "reaching the edge of space" merely refers to going higher than average aeronautical vehicles commonly would

Average aeronautical vehicles I assume include military aircraft around the world, many of which can reach 30-60,000 feet. That would make them average, as there are a lot of them. The concorde therefore falls in to this category.

Your assertion does not meet the text quoted. The concorde wasn't an average plane, and wasn't flying at average flight altitudes.

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EDIT: You say NASA is a fraud, yet you take figures used by NASA every single time they plan and perform missions. So please, explain to me again how NASA is wrong and their figures are wrong and how you use their figures to prove them wrong.

What figures do I use from NASA?

Quote from: MrT on September 14, 2012, 11:59:17 AM

If the atmosphere is what blocks the Sun and causes night, and you are above 90% of the atmosphere at 60,000 feet wouldn't you be able to see the Sun 24 hours a day from that altitude?

Looking through 10% of atmosphere for tens of thousands of miles is still significant.

The fact the remaining 10% stretches a distance before petering out to nothingness is meaningless. That last 10% of atmosphere is near-space, regardless of the space it occupies, since 90% of the atmosphere is below it.

Quote from: Tom Bishop on September 14, 2012, 12:01:45 PM

Quote from: MrT on September 14, 2012, 11:59:17 AM

If the atmosphere is what blocks the Sun and causes night, and you are above 90% of the atmosphere at 60,000 feet wouldn't you be able to see the Sun 24 hours a day from that altitude?

Looking through 10% of atmosphere for tens of thousands of miles is still significant.

The Sun is 3000 miles high, when it's 10,000 miles from the oberver there would be very little atmosphere between the observer and the Sun.

Even if you decide to argue that's not the case (due to some made up perspective phenomenon that only you know about), the fact still remains that the light from the Sun is only going through 10% as much atmosphere, and should therefore remain visible from vastly further away.  The Sun's path as it rotates above the flat Earth would not take it far enough away to be going through as much atmosphere as it does at night from sea level.  So there should be no Sunset or night at 60,000 feet.

Their figures about atmospheric density and composition at different altitudes. Who do you think measured that Tom? Not some joe-shmoe in a hot air balloon. It was by heavily funded teams, some of them being affiliated with NASA.

So 10% is insignificant for when determining whether you are in space or not, but significant for viewing range?

See, that 10% is meaningless. You said so yourself. 10% of 1000 is 100, 100 stretched out over a distance leaves a lot of room between each 1 that makes up that 100. So 10% of atmosphere for tens of thousands of miles is rather meaningless.

The atmosphere may be only 10% as dense, but it is still atmosphere which can build up over distance.

Cardboard may be significantly less dense than carbon fiber, but it's still significant enough to block out light.

Quote from: Lorddave

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You won't see the lights of the city for the same reason you don't see the stars. The light reflected off of the earth is intense and washes out lesser light sources.

Even from the dark part? Are you saying that one bright area is able to cancel out light from a dark area?

Yes. The people who flew on the Concord at near-space all agree that the stars cannot be seen at such heights. The brightness of the earth prevents the stars from being seen.

Quote from: Lorddave

5,000 miles away actually. And yes I am.

The circumfrance of the earth is less than 25,000 miles. If half of it is lit at all times then only about 12,500 miles are lit. If the sun is the center of that circle of light then the sun's rays beam out with a radius of 6,250 miles.

Also, if you claim that the atmosphere is able to block out visible light reflecting off the surface from only a few thousand miles, then how can you see the circle of light's edge? Wouldn't the atmosphere block that as well?

I'm not sure I understand your question. Kindly rephrase.

The atmosphere may be only 10% as dense, but it is still atmosphere which can build up over distance.

Cardboard may be significantly less dense than carbon fiber, but it's still significant enough to block out light.

Various governments and scientific organizations have been studying the density of the atmosphere at various altitudes since the invention of the barometer. Organizations besides NASA have sent aircraft and balloons to high altitudes with barometers attached. Hence, I'm not "using NASA data."

See my cardboard/carbon fiber analogy above. Significance is a matter of context. 10% of a million dollars is significant on a personal level, but insignificant on a corporate or governmental level.

It's not meaningless. A craft at 60,000 feet is above most of the atmosphere, but the atmosphere at 60,000 feet can still build up and accumulate over tens of thousands of miles. This, however, does not contradict the fact that 60,000 feet is above the majority of the atmosphere and is therefore "near-space" in the context of being closer to a vacuum even if it's not "near space" in terms of proximity. This may be the source of the confusion on why some organizations classify "near space" at altitudes far lower than 100km.

Cardboard? Cardboard and carbon fiber are not translucent. Try again Tom. You can't use an opaque object for an analogy of light permeating air.

"Air is a gas. Compared to a solid, air contains very few atoms and is very light. Think about a balloon filled with air compared to a balloon filled with sand. The air balloon is incredibly light compared to the sand balloon. That's because there are many more atoms in sand than in air.

Because air contains so few atoms, light waves run into very few of them when they shine through air. So the air looks transparent. If you put enough dust in the air, the particles of dust absorb the light and the air stops being transparent.

Or, if you make the air incredibly thick, the air absorbs a lot more light. For example, air at sea level is much thicker than air, say, at the top of Mt. Everest. The higher you get, the thinner the air gets. Thin air is much clearer than thick air, because there are less atoms and dust to block the light. When you look straight up at noon, you're looking through a couple of miles of thick air, then about 60 miles of thinner and thinner air, then the vacuum of space. When you look toward the horizon at sunset, you are looking through many miles of thick air at the surface of the Earth, which blocks much of the sun's light. That's why you can't look at the sun at high noon, but you can watch a sunset."

Scientific organizations? Scientists just guess and twiddle their thumbs all based on a round earth. I believe you've said things like this yourself. One must make zetetic observations to find the truth. I guess it's time you go get a weather balloon and make the measurements yourself.

You have this bad habit of using analogies that do not match the situation. In this case, 10% is insignificant because it's stretched out of hundreds of kilometers after that 18.2 km altitude of the Concorde. Like you said, it's not uniformly dense. The initial 90% of the atmosphere is only 16 km high. The last 10% is ~400 km high after that by the figures you gave. That means there's very very little of it per volume.

As I explained above, at 60,000 ft (~18 km) you are still over 400 km from a vacuum. You are nowhere near space, and certainly not on the edge of it. The near space altitudes far lower than 100 km were referring to something like 50-80 km. Not 18 km. Any of those scientists you were talking about would laugh you out of the room if you told them the Concorde was a near-space aircraft.

And as I've said, 10% of atmosphere is near space because it is a state which is near-vacuum. It is not near space in terms of proximity.

Quote from: ThinkingMan on September 17, 2012, 05:44:49 AM

Cardboard? Cardboard and carbon fiber are not translucent. Try again Tom. You can't use an opaque object for an analogy of light permeating air.

The molecules which make up the air are not translucent. You are looking through the space between the molecules which make up the atmosphere.

The higher you get, the thinner the air gets. Thin air is much clearer than thick air, because there are less atoms and dust to block the light.

Quote from: Tom Bishop on September 17, 2012, 09:13:30 PM

And as I've said, 10% of atmosphere is near space because it is a state which is near-vacuum. It is not near space in terms of proximity.

Tom, atmospheric pressure at 60,000 feet is still around 1 psi. 
http://www.engineeringtoolbox.com/standard-atmosphere-d_604.html

The fact still remains that you can see through air, not cardboard or carbon fiber, rendering your analogy invalid

Quote from: Tom Bishop on September 17, 2012, 09:13:30 PM

The higher you get, the thinner the air gets. Thin air is much clearer than thick air, because there are less atoms and dust to block the light.

Right from your post it says thin air is much clearer than thick air.  If the air is what's blocking us from seeing the Sun, shouldn't we be able to see it vastly further away, and therefore all the time, when at an altitude where the air is 90% thinner?  If the air is 90% less dense it should block 90% less light.  If I'm only looking through 10% if the atmosphere I'm looking through at sea level, the Sun should be visible from 10 times further away.

And if the atmosphere is what causes the magnification effect of the Sun, would that effect be reduced as well?  Would the Sun appear smaller as it receded if viewed from altitude?

Quote from: markjo on September 17, 2012, 10:34:15 PM

Quote from: Tom Bishop on September 17, 2012, 09:13:30 PM

And as I've said, 10% of atmosphere is near space because it is a state which is near-vacuum. It is not near space in terms of proximity.

Tom, atmospheric pressure at 60,000 feet is still around 1 psi. 
http://www.engineeringtoolbox.com/standard-atmosphere-d_604.html

How does that compare to the psi on the ground?

Quote from: Tom Bishop on September 18, 2012, 07:00:04 AM

Quote from: markjo on September 17, 2012, 10:34:15 PM

Quote from: Tom Bishop on September 17, 2012, 09:13:30 PM

And as I've said, 10% of atmosphere is near space because it is a state which is near-vacuum. It is not near space in terms of proximity.

Tom, atmospheric pressure at 60,000 feet is still around 1 psi. 
http://www.engineeringtoolbox.com/standard-atmosphere-d_604.html

How does that compare to the psi on the ground?

The better question would be; "how does that compare to the psi of a vacuum?"

You are assuming that air is just barely blocking out the sun at sea level. As seen in the images above, air gets cloudy in only the distance from the observer to the mountain. For arguments sake lets say that the mountains are 9 miles away in those images. At 10% atmosphere we might need a distance of 90 miles to create the same amount of cloudyness.

This is a greater distance yes, but still insignificant when the light source is thousands of miles away horizontally. Perhaps the light lingers a bit longer, but the claim that the atmosphere would be illuminated at all times is still unjustified.

Justified.

so for arguments sake lets say the sun can been seen roughly 4780 miles away so at 10% atmosphere it can be seen roughly 47,800 miles.

Quote from: squevil on September 18, 2012, 03:25:08 PM

so for arguments sake lets say the sun can been seen roughly 4780 miles away so at 10% atmosphere it can be seen roughly 47,800 miles.

Thank you for your justification. We are breaching new FE ground which I have not seen covered before.

My explanation in response to that is that at sea level atmosphere is so thick and foggy that it blocks out all light after 80 miles or so. This is demonstrated by the fact that the mountains in the images I posted have dimmed considerably, while being relatively close to the observer (8-10 miles perhaps). We can see that the atmosphere is not very transparent at all. It is actually rather thick.

The reason the sun is able to shine through the atmosphere despite its fog is because the sun is an intense light source and catches onto the atmosphere like foglights in fog. See the article The Magnification of the Sun in our encyclopedia. When we look at the sun at its setting we are not really looking at the sun, but its image upon the atmosphere.

See this headlight example from the article:



The light from these incoming headlights are a constant size down the highway as far as the eye could see. The light has caught on to the atmosphere and magnifies as the line of cars recede into the distance, appearing to be relatively the same size for as far as the eye can see. Also notice that, while the headlights are magnified, the tail lights are appropriately shrinking into the distance until they are invisible. This is because the red tail lights are not intense enough to catch onto the atmosphere.

It may be that at such heights of 60,000 feet it may be that the atmosphere is so thin that the sun can't catch onto the atmosphere in this manner, its light being diluted normally by a 10% atmosphere. A 10% atmosphere is still considerably thick by your own arguments, seeing as it can still generate lift for a plane.

If all light is blocked out after 80 miles, how come we can see the sun?  Isn't that over 3,000 miles away?

Also, you should try an image of better quality when there isn't some form of fog or rain.

http://farm4.staticflickr.com/3433/3966018026_6ca5bc1acf_b.jpg

This image shows tail lights much farther than your image. 

Quote from: Lorddave on September 18, 2012, 06:04:56 PM

If all light is blocked out after 80 miles, how come we can see the sun?  Isn't that over 3,000 miles away?

The article I posted, the Magnification of the Sun describes what is essentially the fog light effect. If a car 400 feet away from you is in fog it may be entirely invisible. It is not visible until it turns on its headlights. Despite the fact that the fog is blocking out the light of the car, the headlights are powerful enough to catch onto the atmosphere. They are traveling further than they would if they were lesser light sources (ie. the light from the hood of the car in fog).

Quote

Also, you should try an image of better quality when there isn't some form of fog or rain.

http://farm4.staticflickr.com/3433/3966018026_6ca5bc1acf_b.jpg

This image shows tail lights much farther than your image. 

I don't know. I have a hard time seeing the tail lights in the distance in your image.

However, it looks like the oncoming headlights are the same size down the length of the lane. The little dots of the headlights in the distance look as big as the dots of headlights closer to us.

I will see if I can find better examples.

Here's a video of a freeway. You will notice that as the cars approach us the headlights don't seem to be growing. They are relatively constant. The red tail lights of the cars in the lane going away from us do seem to shrink, however.

Focus is a pretty awesome thing isn't it. It allows objects to be sharp or blurry based on a single point. And as we all know, a light that is blurry will appear larger. People with glasses see this when they remove said glasses.

So why is it that when the sun is at its farthest, it's at it's sharpest?
Curious.

Quote from: Lorddave on September 18, 2012, 06:36:07 PM

Focus is a pretty awesome thing isn't it. It allows objects to be sharp or blurry based on a single point. And as we all know, a light that is blurry will appear larger. People with glasses see this when they remove said glasses.

So why is it that when the sun is at its farthest, it's at it's sharpest?
Curious.

I would say that blurriness is a matter of granularity of the surface medium. When a car is behind 400 feet of fog and turns on its headlights what you see is a blurry white spot on the atmosphere, as the fog is close and scattered.

Since the sun is thousands of miles away, it is projecting upon many more atoms and molecules of atmosphere, and can therefore create a more defined image.

lorddave are you saying that there is no moisture in the atmosphere to cause the same effect?
tom is actually making quite a strong argument here for a change. it maybe the wrong explanation but it does make a lot more sense than the usual dribble people can post.