- #1
george95
- 41
- 6
Hello to everyone,
I was wondering if somebody could help me with the specific issue I am interested in: What is the most distant object that can be seen from a particular location, "after" the horizon point?
Here is the graphical preview of my issue.
https://www.dropbox.com/s/5cxxmg570qttmfq/distance_to_horizon2.jpg?dl=0
There is an observer point "O" located on shore, at some altitude h1. I can calculate the D1 distance to point H (the distance to the horizon), with the following formula:
formula source:
http://www-rohan.sdsu.edu/~aty/explain/atmos_refr/horizon.html
(the upper formula assumes some theoretically ideal conditions: no impact of atmosphere layers, air temperature, wind and so on. It assumes the Earth to be a sphere, and takes into account the impact of light refraction also).
My major concern is actually the D2 distance. What I do not understand is how to somehow predict this D2 distance for any location on Earth?
For example, if Mount Everest (8.848 kilometers) the tallest peak on Earth would stand out from the sea, as a lonely island, a person standing on top of it, could have seen the horizon at the distance of 335 kilometers (D2 = sqrt (2*6371*7/6*8.848 + 8.848^2) = 335.8 km).
So I guess in some theoretical imaginary case, D2 can not be larger than 335 kilometers.
But what about other locations around the world, not near to Mount Everest?
I understand that an answer to this question depends on the terrain of that location, it's altitude, and the height of the surrounding mountain peaks. Still does anyone know how can I somehow predict what the D2 distance should be (at least approximately)?
Thank you for the reply in advance.Bernard
I was wondering if somebody could help me with the specific issue I am interested in: What is the most distant object that can be seen from a particular location, "after" the horizon point?
Here is the graphical preview of my issue.
https://www.dropbox.com/s/5cxxmg570qttmfq/distance_to_horizon2.jpg?dl=0
There is an observer point "O" located on shore, at some altitude h1. I can calculate the D1 distance to point H (the distance to the horizon), with the following formula:
D1 in kilometers = sqrt (2*6371*7/6*h1 + h1^2)
formula source:
http://www-rohan.sdsu.edu/~aty/explain/atmos_refr/horizon.html
(the upper formula assumes some theoretically ideal conditions: no impact of atmosphere layers, air temperature, wind and so on. It assumes the Earth to be a sphere, and takes into account the impact of light refraction also).
My major concern is actually the D2 distance. What I do not understand is how to somehow predict this D2 distance for any location on Earth?
For example, if Mount Everest (8.848 kilometers) the tallest peak on Earth would stand out from the sea, as a lonely island, a person standing on top of it, could have seen the horizon at the distance of 335 kilometers (D2 = sqrt (2*6371*7/6*8.848 + 8.848^2) = 335.8 km).
So I guess in some theoretical imaginary case, D2 can not be larger than 335 kilometers.
But what about other locations around the world, not near to Mount Everest?
I understand that an answer to this question depends on the terrain of that location, it's altitude, and the height of the surrounding mountain peaks. Still does anyone know how can I somehow predict what the D2 distance should be (at least approximately)?
Thank you for the reply in advance.Bernard
Last edited: