Is this a triangle?
I would have asked this on a math community but I couldn’t find an active one.
In a spherical geometry, great circles are “straight lines”. As such, a triangle can have two or even three right angles to it.
But what if you go the long way around the back of the sphere? Is that still a triangle?
![A globe with three intersecting great circle segments drawn on it, but one of the segments goes the long way around th back of the globe.](https://kbin.life/media/cache/resolve/entry_thumb/0a/33/0a331f6ed5665d3e4c7799d859eb1bf41a98a3d04a0b147b08643839e22c6849.jpg)