Abstract
We observed the hierarchical triple star Eta Virginis with the Navy Prototype Optical Interferometer and present the first images resolving all three components. The stars in the close pair have a separation between 4 and 9 milliarcseconds. The orbital motions of the stars were followed during the winter and spring of 2002. Preliminary, astrometrically determined orbits of the two components in the close pair by reference to the tertiary were derived, thus enabling the estimation of the mass ratio (1.27) of the components in the close pair. We also determined the relative orbital inclination to be 31 degrees. We describe the model-fitting process to interferometric and spectroscopic data, and discuss some astrophysical component parameters.
