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What is the highest point on Earth as measured from Earth's center?

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Re: What is the highest point on Earth as measured from Earth's center?

#51

Post by [deleted] »

gpm wrote: post #6
magduf wrote: post #3

Earlier quoted context omitted.

When comparing the actual height of a mountain, they're measured from their base (which is whatever elevation the ground they sit on is) to their peak, rather than just looking at their peak altitude. This is how you compare mountains on other planets, and why Mons Olympus on Mars is the tallest mountain in the solar system. For Mauna Kea, the mountain is taller than it looks because its base sits at the bottom of th…

Why is "height from the solid matter base" more correct than "height from the non-gaseous matter base" though. From the perspective of humans, who generally live at the border of gaseous matter not the border of solid matter, I think the latter might make more sense.

[deleted]

Re: What is the highest point on Earth as measured from Earth's center?

#52

Post by ghaff »

saiya-jin wrote: post #48
justinator wrote: post #43

Earlier quoted context omitted.

Looks like a few hours walk and $250 for a guide: https://www.mountainproject.com/route/110735330/standard-rou...

From the description I see on net this is indeed true, with big IF - you already have prior acclimatization to 5000m+. Without it, its almost impossible to make it to the top and back at that altitude, unless you have some super genes. And descriptions mention still 10 hours of hiking and altitude difference of some 1300m. Even though the air around equator is thicker, you would most probably already feel very bad at…

Right. It's not "hard" in the grand scheme of things of climbing 8000m peaks in the Himalayas, highly technical climbs, or even a peak like Denali. However, it's also a far way from pull up to a parking lot and get a little exercise for the vast majority of people. Altitude makes a big difference for most. As you say, there's acclimatization. And also there's a world of difference climbing at 5000m+ relative to climbing relatively near sea level for almost everyone.

Re: What is the highest point on Earth as measured from Earth's center?

#53

Post by mkeespiet »

ghaff wrote: post #52
saiya-jin wrote: post #48

Earlier quoted context omitted.

From the description I see on net this is indeed true, with big IF - you already have prior acclimatization to 5000m+. Without it, its almost impossible to make it to the top and back at that altitude, unless you have some super genes. And descriptions mention still 10 hours of hiking and altitude difference of some 1300m. Even though the air around equator is thicker, you would most probably already feel very bad at…

Right. It's not "hard" in the grand scheme of things of climbing 8000m peaks in the Himalayas, highly technical climbs, or even a peak like Denali. However, it's also a far way from pull up to a parking lot and get a little exercise for the vast majority of people. Altitude makes a big difference for most. As you say, there's acclimatization. And also there's a world of difference climbing at 5000m+ relative to climb…

I can confirm it is difficult. Not in terms of climbing, but in terms of breathing. The higher, the smaller your steps. Above 6.000m do you 3 steps and 10 seconds of gasping for air or more. But the view on the summit, that was the most beautiful one I have every seen. You could see the shadow of the mountain, see below. In my case there where some clouds, which made it even more beautiful. https://80d2853cc4def76b377d-54344bc01a8b066c84096a8e7a3499a...

Re: What is the highest point on Earth as measured from Earth's center?

#54

Post by informatimago »

alanbernstein wrote: post #40
blendo wrote: post #39

So is the peak of Chimborazo the point on Earth with the lowest delta-v to orbit? Compared to a sea level equatorial launch, https://space.stackexchange.com/questions/8486/where-is-the-... claims a 0.2% gravitational advantage due to height, and a 0.1% advantage due to rotational velociy. Small, but not nothing.

Maybe, but how are you going to carry a rocket up there? Even building a rocket sled up a mountain seems infeasible.

You don't carry it!

You dig a tunnel (Boring Company), you vacuum it (hyperloop), and you propulse a rocket (Space X) in it with electromagnets, and lots of batteries (Tesla).

Theorically, you can also come back from space the same way, but 1- you still need to slow down from orbit, 2- you need to be very precise to enter the tunnel. This would allow to reload the battery using electromagnetic braking. Unfortunately, you would need to reverse the orbital speed to come back the way you came from! This is the costly part. This is why Space X lands on sea platforms, not where they took off from.

Re: What is the highest point on Earth as measured from Earth's center?

#55

Post by grecy »

krupan wrote: post #30

"That makes Chimborazo the closest point on Earth to the stars." That statement sold me. If I want to be on the top of any mountain now, it's that one.

I climbed (hiked) Cotopaxi in Ecuador, and you can see Chimborazo from the summit.

Cotopaxi is 5,897m, so it's still further from the center of the earth than Everest.

Full story of my climb and photos here http://theroadchoseme.com/cotopaxi-summit

Re: What is the highest point on Earth as measured from Earth's center?

#56

Post by PhasmaFelis »

jake-low wrote: post #29
wallace_f wrote: post #21

Earlier quoted context omitted.

>However, an apples-to-apples comparison would use the dry prominence of Everest too, which is the distance from the bottom of the Challenger Deep (-10,911m) to the summit. This would make Mauna Kea the second tallest mountain by topographic prominence if the Earth had no oceans What? This does not make sense, if I am not mistaken? Topographic prominence would place Mauna Kea as the tallest (highest peak from base co…

Think about it this way: imagine standing at the bottom of the Challenger Deep. Draw a small circle around yourself on the ocean floor. Now step outside the circle. Because you're standing on a spherical object (Earth), the area outside your circle isn't infinite like it would be on a plane. It's another finite region, which covers almost the entire Earth, and contains both yourself (standing just beside the lowest p…

Is this measurement conceptually useful, or is it completely arbitrary? I thought it was an attempt to rigorously define "surrounding terrain" for purposes of measuring a mountain's height above the surrounding terrain, but if it defines the Challenger Deep as "surrounding" Everest, that's topologically interesting but doesn't seem like a useful way of thinking about geology.

Re: What is the highest point on Earth as measured from Earth's center?

#57

Post by whoopdedo »

Nition wrote: post #7
magduf wrote: post #3

Earlier quoted context omitted.

When comparing the actual height of a mountain, they're measured from their base (which is whatever elevation the ground they sit on is) to their peak, rather than just looking at their peak altitude. This is how you compare mountains on other planets, and why Mons Olympus on Mars is the tallest mountain in the solar system. For Mauna Kea, the mountain is taller than it looks because its base sits at the bottom of th…

I get the impression that the asker knows that but that their question is more like, is there any official way to define where the mountain starts? Could we keep tracking the side of Everest right down into a far-off ocean trench and say it's now the tallest again, it's just also really wide? I guess you're looking for obvious local minima. If the land slopes back up a lot or stays mostly flat for a long time it's pr…

My definition would involve some definition of geological homogeny such that you could classify the terrain as mountain and not-mountain. Probably based on whether it was involved in the process that formed the mountain.

Re: What is the highest point on Earth as measured from Earth's center?

#58

Post by athenot »

mkeespiet wrote: post #53
ghaff wrote: post #52

Earlier quoted context omitted.

Right. It's not "hard" in the grand scheme of things of climbing 8000m peaks in the Himalayas, highly technical climbs, or even a peak like Denali. However, it's also a far way from pull up to a parking lot and get a little exercise for the vast majority of people. Altitude makes a big difference for most. As you say, there's acclimatization. And also there's a world of difference climbing at 5000m+ relative to climb…

I can confirm it is difficult. Not in terms of climbing, but in terms of breathing. The higher, the smaller your steps. Above 6.000m do you 3 steps and 10 seconds of gasping for air or more. But the view on the summit, that was the most beautiful one I have every seen. You could see the shadow of the mountain, see below. In my case there where some clouds, which made it even more beautiful. https://80d2853cc4def76b37…

That is beautiful! And thanks for the feedback.

Re: What is the highest point on Earth as measured from Earth's center?

#59

Post by SilasX »

whoopdedo wrote: post #57
Nition wrote: post #7

Earlier quoted context omitted.

I get the impression that the asker knows that but that their question is more like, is there any official way to define where the mountain starts? Could we keep tracking the side of Everest right down into a far-off ocean trench and say it's now the tallest again, it's just also really wide? I guess you're looking for obvious local minima. If the land slopes back up a lot or stays mostly flat for a long time it's pr…

My definition would involve some definition of geological homogeny such that you could classify the terrain as mountain and not-mountain. Probably based on whether it was involved in the process that formed the mountain.

Yeah, that was what I was hoping/expecting the definition would use, that mountains come from some plate interaction involving lava which would provide a natural boundary between "mountain" and "rest of earth".

Re: What is the highest point on Earth as measured from Earth's center?

#60

Post by magduf »

SilasX wrote: post #59
whoopdedo wrote: post #57

Earlier quoted context omitted.

My definition would involve some definition of geological homogeny such that you could classify the terrain as mountain and not-mountain. Probably based on whether it was involved in the process that formed the mountain.

Yeah, that was what I was hoping/expecting the definition would use, that mountains come from some plate interaction involving lava which would provide a natural boundary between "mountain" and "rest of earth".

I think a lot of mountains don't involve lava at all, they're just the product of continental plates running into each other. I'm pretty sure Everest is an example of this. Hawaii is the opposite; those mountains don't involve plates at all, they're solely the product of lava.
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