When looking at the MODIS grid  and compare it to how the sinusoidal projection is distorted, I wonder how to both practically and formally describe the distortion factor for each MODIS grid tile.
By practically I mean, what's a center tile's (e.g.
row 8, col 18) width and height in meters on ground compared to a tile of a region that is rather distorted on the sinusoidal projected map, like
row 2, col 14?
My understanding is that, by example on the grid shown at  which should be a 1km resolution MODIS grid, each tile should be approximately
1200km * 1200km, but is that approximation nearly the same for mentioned tile regions?
And by formally I mean, how to mathematically describe the distortion factor for MODIS tiles?