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We present results of long-term high-frequency VLBI monitoring of therelativistic jet in 3C279, consisting of 18 epochs at 22 GHz from 1991 to 1997and 10 epochs at 43 GHz from 1995 to 1997. Three major results of this studyare: apparent speeds measured for six superluminal components range from 4.8 to7.5 c (H_{0}=70 km s^{-1} Mpc^{-1}, q_{0}=0.1), variations in the total radioflux are due primarily to changes in the VLBI core flux, and the uniform-spherebrightness temperature of the VLBI core is about 1 x 10^{13} K at 22 GHz after1995, one of the highest direct estimates of a brightness temperature. If thevariability brightness temperature measured for 3C279 by Lahteenmaki & Valtaojais an actual value and not a lower limit, then the rest-frame brightnesstemperature of 3C279 is quite high and limited by inverse Compton effectsrather than equipartition. The parsec-scale morphology of 3C279 consists of abright, compact VLBI core, a jet component (C4) that moved from about 2 mas toabout 3.5 mas from the core during the course of our monitoring, and an innerjet that extends from the core to a stationary component, C5, at about 1 masfrom the core. Components in the inner jet are relatively short-lived, and fadeby the time they reach about 1 mas from the core. The components have differentspeeds and position angles from each other, but these differences do not matchthe differences predicted by the precession model of Abraham & Carrara.Although VLBI components were born about six months prior to each of the twoobserved gamma-ray high states, the sparseness of the gamma-ray data prevents astatistical analysis of possible correlations.Comment: 30 pages, including 10 figures, emulateapj.sty, accepted to The  Astrophysical Journal Supplemen

Kinematics of the Parsec‐Scale Relativistic Jet in Quasar 3C 279: 1991–1997