Octant of a sphere

In geometry, an octant of a sphere is a spherical triangle with three right angles and three right sides.

It is sometimes called a trirectangular (spherical) triangle.

[2] For a sphere embedded in three-dimensional Euclidean space, the vectors from the sphere's center to each vertex of an octant are the basis vectors of a Cartesian coordinate system relative to which the sphere is a unit sphere.

[3] The octant can be parametrized using a rational quartic Bézier triangle.

[4] The solid angle subtended by a spherical octant is π/2 steradian or one-eight of a spat, the solid angle of a full sphere.