Flat Vs Globe K-Rino Featuring Neil Disgrace Tyson, Michio Kaku, Bill Nye And William Shatner

Flat Earth Debate

FOR ALL INTENTS AND PURPOSES, WE LIVE ON A FLAT SURFACE....

The term "tangential plane" or more commonly "tangent plane" in the context of navigation, surveying, and engineering often refers to a method of projection, specifically when projecting a portion of the Earth's surface onto a flat plane. This method is essential for creating maps or conducting detailed land surveys over relatively small areas where the Earth's curvature has minimal impact. Here are some areas where tangent plane coordinates are used:

1. **Plane Surveying**: For small areas (typically less than about 250 km^2), the Earth's curvature is often negligible for many practical purposes. Plane surveying assumes a flat Earth for these small regions, and all calculations are made on this tangent plane.

2. **Local Coordinate Systems**: Many engineering projects, like construction sites or mines, will define a local tangent plane coordinate system. This system is unique to the specific project area, and all measurements and calculations are referenced to this local system.

3. **State Plane Coordinate System (SPCS)**: In the United States, the SPCS divides states into zones. Each zone uses a tangent plane (or secant plane for some larger zones) projection to create a flat coordinate system optimized for that region. This system allows for high accuracy while using simple plane geometry for calculations.

4. **Cartography**: While larger world maps will use more complex projections, local or regional maps might use a tangent plane projection if it provides the necessary accuracy for the map's intended purpose.

5. **Geometric Geodesy**: When transforming global or geodetic coordinates to local Cartesian coordinates for precise measurements or calculations, a tangent plane based at an observer's location might be used.

6. **Civil Engineering**: For projects like road or railway design in relatively flat regions, a tangent plane coordinate system can simplify calculations.
Was this datum line actually at sea level all the way across the United States of america, over 20,000 separate surveying points all at sea level?

"The National Geodetic Vertical Datum of 1929 (NGVD29), previously referred to as Sea Level Datum of 1929, was the network of over 20,000 miles of levels constrained to Mean Sea Level (MSL) at 26 tide stations around North America. The network was warped due to variations in the Local Mean Sea Level (LMSL) at those 26 tide stations. These variations introduced errors into the network adjustment. The datum is not mean sea level and was renamed the National Geodetic Vertical Datum of 1929 in 1973."

the Mean Sea Level Datum of 1929 is a collection of 20,000 surveying points that are all level?!

It's essential to note that while the tangent plane simplifies calculations, it does introduce errors over larger distances due to the Earth's curvature. However, for many practical applications over small areas, these errors are minimal and often considered acceptable given the benefits of simplification.