Hydrogen Lyman‐α (1216 A) measurements were made on a continuous basis by a two‐channel photometer on Ogo 5 from March 1968 to June 1971. The highly elliptical orbit provided measurements of both the outer geocorona and of the 1216‐A sky background emission, since geocoronal scattering is minimal at the apogee distance of 150,000 km. We present selected data (through 1970) and an interpretation of the three principal discoveries to date, namely, (1) a pronounced antisolar enhancement of the geocoronal scattering beyond 70,000 km, which we believe is evidence for a hydrogen ‘geotail’ produced by solar Lyman‐alpha radiation pressure; (2) a clear correlation of periodic variations in the sky background emission with solar activity associated with solar rotation; and (3) an annual variation of the 1216‐A sky background emission, caused by the earth's orbital motion within the cavity created by the solar wind in the nearby interstellar hydrogen.

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Ton 34 recently transitioned from non-absorbing quasar into a BALQSO.Here, we report new HST-STIS observations of this quasar. Along with CIV absorption, we also detect absorption by NV+Lyα and possibly O VI+Lyβ. We follow the evolution of the CIV BAL, and find that, for the slower outflowing material, the absorption trough varies little (if at all) on a rest-frame timescale of ∼ 2 yr. However, we detect a strong deepening of the absorption in the gas moving at larger velocities (−20, 000 -−23, 000 km s −1 ). The data is consistent with a multistreaming flow crossing our line of sight to the source. The transverse velocity of the flow should be ∼ few thousand km s −1 , similar to the rotation velocity of the BLR gas (≈ 2, 600 km s −1 ). By simply assuming Keplerian motion, these two components must have similar locations, pointing to a common outflow forming the BLR and the BAL. We speculate that BALs, mini-BALs, and NALs, are part of a common, ubiquitous, accretion-disk outflow in AGN, but become observable depending on the viewing angle towards the flow. The absorption troughs suggests a wind covering only ∼20 % of the emitting source, implying a maximum size of 10 −3 pc for the clouds forming the BAL/BLR medium. This is consistent with constraints of the BLR clouds from X-ray occultations. Finally, we suggest that the low excitation broad emission lines detected in the spectra of this source lie beyond the wind, and this gas is probably excited by the shock of the BAL wind with the surrounding medium.

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