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An identification list is presented for the visible spectra of Pi Cet (B7 V), 36 Lyn (B8 IIIp), and 134 Tau (B9 IV). Equivalent widths are measured on medium dispersion plates of 7.0 and 12.4 A/mm, and the photographic plates are digitized using a PDS 1010A microdensiometer. The effective temperature and gravity of the three stars are estimated

The joint consideration of theoretical and observational arguments is used to conclude that two different spot populations co-exist in the Sun.

The discrete structure in the 5 min velocity oscillations of the solar surface has been confirmed by a re-analysis of data obtained between 1976 and 1979, and in addition a preliminary analysis of 1980 data show excellent consistency of the determined frequencies over the five year period. It is further shown that atmospheric transparency, as

Evidence for the rapid internal rotation of the sun obtained from Doppler shift measurements of the Fraunhofer absorption lines is reported. An improved version of the Doppler shift optical resonance spectrometer was used to record the resonantly scattered intensities corresponding to the two wings of the 769.9-nm Fraunhofer absorption lines of

An attempt is made to confirm the observation of Allen (1980) of a 3.3-micron emission feature attributed to thermal dust emission in the quasar 3C 273. Spectrophotometric observations of 3C 273 were obtained on May 18, 19 and 24 with the 1.5-m telescope of the Mount Lemmon Observatory. No evidence is found for the 3.3-micron feature in excess of 7