Position data of sunspot groups from the period 1874-1902 are used to investigate the differential rotation of the Sun and the meridional motions of the sunspots. The equatorial velocity is higher than in the period 1940-1968 investigated by Balthasar and Wöhl (1980), while differences between the northern and southern hemispheres are less. For

The 1-8A band of synodic full-disc solar X-rays (1-8A) W/m(2) were measured nearly continuously from 1975 to 1981 aboard the SMS-1, SMS-2, GOES-1, GOES-2, and GOES-3 satellites. The 1-8A band of X-rays are proportional to the emission measure at coronal heights at temperatures greater than 2,000,000 K. A practical method of describing solar 1-8A

The IUE observed AB Aur, HD250550, and BD + 46 deg 3471 at high resolution in the range 2000 to 32000 A. The MgII resonance line profiles all show a P Cygni structure, with an intense emission, and a shortward wing velocity in the absorption component of 300 to 600 km/sec. In HD 250550, the Fe II line spectrum exhibits a shell phenomenon: all lines

Spectra of six main sequence stars with spectral types from F0 to G8 were obtained with the IUE long wavelength spectrograph at high resolution. Four or more spectra of each object were taken over a period of 3.5 years, supplemented by archive spectra from IUE of the same type. Quantitative analysis of the Mg II h and k emission cores from these

The width distribution of the penumbral filaments is estimated using white light photographs obtained with a vacuum, Newtonian type telescope. Observations were made during the solar eclipse of June 1973 in order to allow simultaneous recording on each frame of the moon limb crossing on the photosphere, as well as the sunspot and penumbra of

We report observations of NGC 6334N, Ml7 5W, W 51 and DR2l(OH) in the J = 4→3 transition of HCN at 354GHz. These results are combined with previously obtained J=1→0HCN data to determine molecular abundances X(HCN) ˜4 × 10-11 -4 × 10-12, and characteristic line excitation zone densities n(H2)˜106 cm-3. These results are at variance with previous