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We report results from 5-day VLBI observations of the well-known quasar 3C279 at 1.3 mm (230 GHz) in 2011. The measured nonzero closure phases ontriangles including stations in Arizona, California and Hawaii indicate thatthe source structure is spatially resolved. We find an unusual inner jetdirection at scales of $\sim$1 parsec extending along the northwest-southeastdirection (PA = $127^{\circ}\pm3^{\circ}$), as opposed to other (previously)reported measurements on scales of a few parsecs showing inner jet directionextending to the southwest. The 1.3 mm structure corresponds closely with thatobserved in the central region of quasi-simultaneous super-resolution VLBAimages at 7 mm. The closure phase changed significantly on the last day whencompared with the rest of observations, indicating that the inner jet structuremay be variable on daily timescales. The observed new direction of the innerjet shows inconsistency with the prediction of a class of jet precessionmodels. Our observations indicate a brightness temperature of $\sim8\times10^{10}$ K in the 1.3 mm core, much lower than that at centimeterwavelengths. Observations with better uv coverage and sensitivity in the comingyears will allow the discrimination between different structure models and willprovide direct images of the inner regions of the jet with 20--30 $\mu$as (5--7light months) resolution.

Fine-scale structure of the quasar 3C 279 Measured with 1.3 mm very long baseline interferometry