The prolate solar chromosphere
نویسندگان
چکیده
We present a comparative analysis of the chromospheric solar limb prolateness, using strictly simultaneous Hα ground-based observations and HeII space-based observations. The typical prolateness is found to be ∆D/D = 5.5 × 10−3 in HeII and 1.2 × 10−3 in Hα. The first measurements in the 30.4 nm HeII line over a period of two years, as well as coronal data, are discussed to explore further the origin of the prolateness and its possible consequences.
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