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The Stellar Observations Network Group (SONG) is being developed as a network of 1-meter spectroscopic telescopes designed for and primarily dedicated to asteroseismology. It is patterned after the highly successful GONG project. The Danish prototype telescope will be installed in Tenerife in early 2011. Ultimately we hope to have as many as 8 identical nodes providing continuous high-resolution spectroscopic observations for targets anywhere in the sky. The primary scientific goals of SONG are asteroseismology and the search for Earth-mass exoplanets. The spectroscopic requirements for these programs push the limits of current technology, but the resulting spectrograph design will enable many secondary science programs with less stringent requirements. Doppler imaging of starspots can be accomplished using continuous observations over several stellar rotations using identical instrumentation at each node. It should be possible to observe the evolution of starspot morphology in real-time, for example. We discuss the design and status of the SONG project in general, and we describe how SONG could be used to probe short timescale changes in stellar surface structure.

Throughout its eighteen years of operation, the International Ultraviolet Explorer has afforded us the opportunity to make many new discoveries regarding the nature of the outer atmospheres of magnetically active, late-type stars. High-resolution spectra obtained continuously throughout the rotational cycle of rapidly-rotating stars have been used to map the spatial structure of the magnetic active regions in stellar chromospheres. The RS CVn-type binary system AR Lacertae has been observed intensively at 3 epochs, with additional observations with less complete phase coverage was obtained at 4 other epochs. Taken together, we are able to probe the evolution of atmospheric structure of AR Lac over a 13-year timeline. I briefly review techniques of chromospheric emission line mapping, and I summarize the IUE results for AR Lac, V711 Tau, EI Eri, V1794 Cyg, and TY Pyx. I conclude with a description of chromospheric imaging programs (present and future) that make use of the Hubble Space Telescope.

Photometric and spectroscopic variability of late-type stars frequently has been interpreted as evidence of magnetic activity. The standard picture of stellar activity – inherited from solar observations – includes cool, dark “spots” in the photosphere and hot, dense regions in the chromosphere and coronae. The immediate cause of each of these phenomena is a closed topology of the local magnetic field. Because stars appear as mere points of light, these localized phenomena have not been directly resolvable on stars other than the Sun. Most observed effects are produced by an asymmetric distribution of starspots. If the distribution is symmetric, it would escape detection by most current techniques of light-curve and line-profile modeling. Even more troubling, the stellar properties measured with these techniques describe only a difference between contrasting hemispheres, not an absolute measure.

Several groups at this meeting are presenting maps of the spatial distribution of either brightness or effective temperature in the photospheres of rapidly-rotating, late-type stars. It is generally believed that structure seen in these maps traces the magnetic topology, in analogy with the Sun. We expect the structure of the outer atmospheres (i.e., chromosphere and corona) of these stars to be even more directly tied to the magnetic topology; the magnetic structure is three-dimensional. In order to probe the radial dimension of stellar atmospheres, we need to combine maps of the spatial distribution of emission from chromospheres and coronae with these detailed photospheric maps.Along with collaborators at Armagh, Catania, Boulder, Paris, Helsinki, and Stony Brook, I have been obtaining high-dispersion ultraviolet spectra of several rapidly-rotating, late-type stars using the IUE spacecraft. I discuss results for two stars, El Eridani and HD 199178, for which photospheric maps are presented elsewhere at this conference.

I discuss the general problem of determining the spatial structure in the outer atmospheres of active, late-type stars. There are several major differences between the problems of imaging photospheres and of imaging chromospheres. Because of these differences, chromospheric spectral imaging must be based on a direct deconvolution of the observed emission line profiles. I present results based on IUE spectra of AR Lac (=HD 210334).

Approximately 10 very bright flares in RS CVn systems have been observed with the IUE. In several cases, high-resolution spectra of the Mg II k line profiles were obtained before, during, and after the flare. Such data permit us to measure the position and size of the flaring region, the amount of line broadening, and any systematic flow velocity. In two cases, several spectra were obtained during the flare decay, permitting us to study the change in these quantities during the flare decay.

An unconstrained four gaussian fit to the Mg II profile near the flare peak indicates that the flare occurred near the central meridian of the K1 IV star, perhaps above a spot. A more likely fit to the same data places the flare at +90 ±30 km s–1 relative to the K1 IV star, indicating significant downflowing plasma.