Latitude variations in interplanetary Lyman-α data from the Galileo EUVS modeled with solar He 1083 nm images
Abstract
Observations of interplanetary Lyman-α obtained by the Galileo Extreme Ultraviolet Spectrometer (EUVS) experiment near solar maximum in 1990 show a distinct migration in the upwind brightness maximum from 36±5°N to 6±5°N ecliptic latitude over a period of several months. Our earlier models based on solar Lyman-α flux proxies appropriate for use in the ecliptic plane ( Pryor et al., 1992; Ajello et al., 1994) capture the solar rotation effects present in the data, but do not reproduce this latitude migration. We introduce a new type of model that uses He 1083 nm images to produce a proxy for Lyman-α as a function of both solar longitude and latitude. This model reproduces the observed latitude migration of the Lyman-α brightness maximum.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- July 1996
- DOI:
- 10.1029/96GL01978
- Bibcode:
- 1996GeoRL..23.1893P
- Keywords:
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- Interplanetary Physics: Interstellar gas;
- Solar Physics;
- Astrophysics;
- and Astronomy: Ultraviolet emissions