Monitoring of active late-type dwarfs, spectroscopically with high resolution (λ/Δλ ≡ 105) and high S:N (>300) round their activity cycles, principally in the Ca II H resonance line, offers techniques to explore, (1) plage filling factors, (2) 3-dimensional chromospheric velocity fields, (3) maps of surface activity via "Doppler Imaging". In this

High resolution bidimensional optical spectroscopy in H-alpha line, N II forbidden line at 6548 and 6583 A, and S II forbidden line at 6717 and 6713 A, of the bipolar nebula S 106 are reported. The resulting H-alpha velocity maps show strong variations in the emission line profiles along the nebula, a situation which is duplicated in other lines

High signal to noise spectra are required in chromospheric modelling because chromospheric emission lines are formed in a boundary layer under conditions of NLTE and in non-hydrostatic equilibrium, as well as in multiple magnetically-controlled streams, with horizontal structure on several scales, and vertical velocity fields. To obtain useable

Data obtained at Izaña (Tenerife) and Haleakala (Maui), using optical resonant scattering with a potassium vapour cell over the years 1980 - 84, are used to determine the frequencies of the low l p modes. Possible variation in these frequencies with the solar cycle are investigated.

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