Planes (geometry)

thumb|upright=1.3|As seen from the orbiting Earth, the [[Sun appears to move with respect to the fixed stars, and the ecliptic is the yearly path the Sun follows on the celestial sphere. This process repeats itself in a cycle lasting a little over 365 days.]]

projection of the Earth's equator out into space

intersection of a body in 3D space with a plane

angle between two planes in space

type of wave propagating in 3 dimensions

geometrical plane in which an orbit lies

In geometry, a set of points in space are coplanar if there exists a geometric plane that contains them all. For example, three points are always coplanar, and if the points are distinct and non-collinear, the plane they determine is unique. However, a set of four or more distinct points will, in general, not lie in a single plane. thumb|An example of coplanar points Two lines in three-dimensional space are coplanar if there is a plane that includes them both. This occurs if the lines are parallel, or if they intersect each other. Two lines that are not coplanar are called skew lines.

plane passing through the barycenter of a planetary system, perpendicular to its angular momentum vector

process used to make microchips

mirror with a flat reflecting surface

device used in surveying and related disciplines to provide a solid and level surface on which to make field drawings, charts and maps

plane of reference that divides the sphere into two hemispheres

thumb|170px|Parallel plane segments with the same orientation and area corresponding to the same bivector .

plane used to define orbital elements

geometrical concept about a set of planes intersecting in a line

terms used to denote the orientation of a geologic feature

relating to optical reflection

length in solid geometry

particular kind of plane geometry, built upon some affine planes by adding one point

intersection of a line and a plane can be the empty set, a point, or a line

type of Benz planes

image plane located between an eye point and an object