EntityQ2755244· pop 13· linked from 15 articleseccentricity vectorSign in to savein celestial mechanics, a dimensionless vector with direction pointing from apoapsis to periapsisConnectionsapsisEntityorbital eccentricityEntityInternational Standard Book NumberEntityvelocityEntityorbitEntityEuclidean vectorEntitycelestial mechanicsEntityposition vectorEntityargument of periapsisEntitydimensionless quantityEntityLaplace–Runge–Lenz vectorEntityosculating orbitEntityKepler orbitEntitystandard gravitational parameterEntitySpecific relative angular momentumEntityCategoriesOrbitsVectors (mathematics and physics)