# What do we call these points?

• December 21st, 2010, 01:20 PM
Eagle9
What do we call these points?
Good day!
On the image depicted below you see the Earth and Space Elevator, both they are tilted to plane of ecliptic at 23 degrees. The plane of ecliptic is shown as dark-green circle, Earth’s equator-grey ring and big red ring is the imaginary path drawn by the Space Elevator’s counterweight (there is inscription “Space Elevator”) at the certain altitude.

You can also see four yellow balls placed at that red ring. They are placed at some certain point of the ring, more precisely balls 0 and 180 are placed at this ring and at the plane of ecliptic at the same time, in other words they are placed exactly at the points where the red ring crosses plane of ecliptic (this can happen only at two places). Ball 90 is placed at the point where the red ring occupies the highest position in space (relative to the plane of ecliptic), ball 270-the lowest position.

I would like to know this: when I write that the Earth (with the Space Elevator) rotates around its axis the counterweight reaches these four point during 24 hours, so what do we call these points/balls? What can I write in my paper when I want to state that the counterweight reached on of these points? As far as I know balls 0 and 180 are called orbital nodes (http://en.wikipedia.org/wiki/Orbital_node), what about the points 90 and 270?

http://img221.imageshack.us/img221/9764/56208810.jpg
http://img221.imageshack.us/img221/9764/56208810.jpg
• December 22nd, 2010, 08:20 AM
Eagle9
• December 23rd, 2010, 03:29 AM
Cyberia
Right Angle Non-Orbital Nodes?

No reason why you cannot think up a new word or term to describe them if there is nothing as yet.
• December 23rd, 2010, 07:24 AM
Eagle9
Cyberia

Quote:

Right Angle Non-Orbital Nodes?
Too long name :)

Quote:

No reason why you cannot think up a new word or term to describe them if there is nothing as yet.
Of course I can invent new name, but first of all I would like to find out if they have names generally or not; I asked this question at many web-forums but nobody was able to answer, so I think that if in my paper I write something like this: “When the Space Elevator’s counterweight reaches (point(s) of) maximum elevation/depression……………..” it would be OK, what do you think? One person offered this terms-point(s) of maximum elevation/depression (relative to plane of ecliptic) and apparently they would be suitable names :)
• December 23rd, 2010, 02:24 PM
Zwirko
I carried out some searches and saw these points referred to several times as the "highest point" and the "lowest point". Not a cool nomenclature and one that could easily confuse.
• December 24th, 2010, 08:06 AM
Eagle9
Quote:

Zwirko
I carried out some searches and saw these points referred to several times as the "highest point" and the "lowest point"
Yes, these terms are also acceptable I think :) actually "highest point" and "point of maximum elevation" are the same :)