The Summit

[HikerBob]

So what is the furthest ... anyone has been able to see (aided or unaided) from atop the Rockpile?

Ohhhh - about 93 million miles (Further at night)

More down to Earth - as an example of distant viewing of city scapes I have seen Boston downtown from Wachusett at about 45 miles distant. It was a fairly clear November day and the taller buildings could be discerned with the naked eye.

Other than the curvature issue the biggest handicap to distant views is moisture in the atmosphere. Clear, cold winter days are best.

This thread has wandered some, but still very interesting.

Bob

[mk10]

Ah, you are re-wording what I actually said. First I said "this is a good simple way to get an estimate" and I did specify that the answer would be an approximation of the line of sight, I never mentioned surface distance 'D' because that isn't where my line-of-sight travels. The scale in your drawing, although done for illustrative purposes, is quite distorted because the ratio of the radius to the summit elevation is about 4000:1.

If we were to be truly technical about this we would actually have to traverse the route along the surface. What we would find is that the surface isn't flat and so the true distance would not be the arc but some distance greater because of all the ups and downs. My point was simply, that the estimate could be done simply, without making this needlessly complex, and I tried to stress this point in my post.

When talking about straight line distance between two geographical points we typically use great circle distances. The distance between MW and WTC that we've been using is not the up and down distance traversed over the mountains (and through the woods, to grandma's house we go ), but the great circle distance. Your method merely left out a simple conversion from line of sight to surface distance, that's all. I should also point out that Patrad Fischroy's technique from several posts ago left out this conversion as well, where:

Take the average elevation of the two endpoints, if this is greater than the maximum visual interference then the two points could be seen.

should have read:
Take the average elevation of the two endpoints and multiply this figure by the cosine of 1/2 arc angle, if this is greater than the maximum visual interference then the two points could be seen.

Unless we are talking about extremely tall structures separated by great distances and we need pinpoint accuracy, it doesn't really matter. I'm just being a little bit anal-retentive here, just ignore me.

Art and Patrad, you both still get an A+ on your papers.

[Arthur Dent]

mk10-"I'm just being a little bit anal-retentive here, just ignore me."

Anal-retentive I understand and that's why I posted my reply!

A friend of mine had a tee shirt that said: "Is anal-retentive hyphenated?"

[John_Calif]

Yes, this thread evolved from a discussion of line of sight between Mt.Wash/WTC and applied theory to a discussion purely hypothetical in nature--and although interesting in its own right, a hypothetical finding is absolutely meaningless in any practical sense.
Mark

Interesting to see your interpretion of the topic of conversation in this thread. The original question was actually about seeing a photograph of the WTC taken from the top of Mt Washington. It was raising a question about a 'myth'. What I've tried to do in resurrecting this thread is to explore this 'myth'- and only part of that exploration involves geometry and actual visual observation. And I've done my best to participate in that part of the discussion.

An equally interesting topic is how this story came about. Was it nothing more than a simple hoax? Or was it a hypothetical illustration (e.g. ignoring the curvature of the earth) designed to shed light on the relative prominence of the Mountain in relation to its surroundings? (Something that was then twisted into the claim of an actual photograph of the WTC.) Perhaps the purpose of the original illustration was to point out something that is fascinating about Mt Washington but which is not readily apparent and has nothing to do with 'sense based' observation?

So when you say 'a hypothetical finding is absolutely meaningless in any practical sense' what kind of 'practicality' are you referring to? What are you trying to get 'accomplished'? Appreciating the topography of Mt Washington in relation to its surroundings by utilizing a hypothetical illustration is very 'practical'. It suites the purpose quite well!

There's nothing wrong with the intense geometry and field observations you guys are employing but just be clear that you're limiting the discussion to geometry and sight. You're missing, well... the bigger picture! Confucious say: Not all that can be seen is perceived by the eyes...

I mean, if I told you that it would take 500 billion basketballs to fill the Grand Canyon would you point out that no factory could possibly manufacture that many basketballs and that not enough trucks exists to possibly tranport them to the rim and that my notion was utterly impractical???

Seems like we take different approaches to things. The 'Myers-Briggs Personality System' would say that you are a 'SENSOR', which is someone who relies upon data collected via the 5 senses to understand the world. And I am an 'INTUITOR', which is someone who values patterns, possibilities, interdependencies and abstraction to understand the world. Both methods are effective depending upon what a person is seeking to investigate, or in this case, appreciate.

[mk10]

So when you say 'a hypothetical finding is absolutely meaningless in any practical sense' what kind of 'practicality' are you referring to? What are you trying to get 'accomplished'? Appreciating the topography of Mt Washington in relation to its surroundings by utilizing a hypothetical illustration is very 'practical'. It suites the purpose quite well!

I didn't mean to imply that the answer to every hypothetical question is completely useless. Seemingly esoteric studies often result in findings which can be generalized to practical applications far distant from the original area of research. But finding whether or not there is an unimpeded line of sight (sans curvature and other factors) from MW to WTC is only practical in the sense that an interesting and entertaining trivia question was answered. Yes, one can use this answer to help appreciate the area's topography, but a topographical map would probably be a better tool for that.

But enough of my babbling, let's focus on what's really important… the Grand Canyon has a volume of approximately 2500 cubic miles, a regulation sized basketball has a diameter of roughly 9 inches, a certain percentage of volume will obviously be occupied by the voids between the packed balls; and since the basketballs will simply be dumped into the canyon (instead of tightly fitted in a crystalline hexagonal lattice) we can use a conservative value of about 40 as the percentage of volume which will be occupied by those voids…

[Brad]

If it wasn't for the atmosphere the sun would rise approximately 7 minutes later than we see it rise. It would also set 7 minutes earlier.

Now I know why I am always 7 minutes late to meetings.

[John_Calif]

Ha! I knew you were going to write that about the basketballs

It would be interesting to have some old timer tell us what the heck the WTC myth was all about anyway. Not having the actual story detracts from our discussion and leaves me only theroetically searching for something cool about it. As you suggest, the topo map posted earlier in this thread shines the brightest light on the topography down to the Big Apple.

By the way, although I grew up in CT I have never been to the top of MW. I set out alone for the summit one summer day in 1988 just before I moved to California. As I got about 3/4 of the way up not only did the weather seem ominous but as I hiked above the tree line I suddenly felt earily 'exposed' and everything seemed downright spooky. Hard to descrrbe but a bit like 'The Twilight Zone'. That's when I decided to turn around. Gotta go back some time and face that demon. I'm going to a funeral in Ct in a few days but doubt I'll have time to get up to scamper up to NH to do so. If I do, however, I'll look for faraway buildings down in NYC- just to make sure all you guys are being straight with me...

[Yankee]

Understand the science, but always back it up with real life observation.

[John_Calif]

Understand the science, but always back it up with real life observation.

You, of course, miss the point. There is no 'observation' to be made here! How do you 'observe' the fact that IF THE EARTH WERE FLAT there would have been nothing but air in between the top of Mount Wahington and the top of the World Trade Center? You see, BECAUSE THE EARTH IS NOT FLAT you can't confirm this fact with 'observation'. I'm a little perpexed why you miss this simple point...

I mean, if I told you that if all the pennies in the world were stacked on top of each other that they would create a stack xx miles high- would you then respond that this couldn't be true because you don't 'observe' any such stack of pennies????