One can make a color-color plot by arranging stars in a two-dimensional graph, where each axis measures a different color index. Below are some examples from the SDSS, which uses a set of broadband filters called (u, g, r, i, z); they are very roughly equivalent to (U, B, R, I, _).
regime - the organization that is the governing authority of a political unit; the government reduced taxes; the matter was referred to higher authorities. authorities, government.
Definition of tyrant for Students. 1  1 : a ruler who has no legal limits on his or her power. 2  2 : a ruler who exercises total power harshly and cruelly. 3  3 : a person who uses authority or power harshly My boss is a real tyrant.