Helium Abundance

Helium makes up about four percent of the solar wind, but its abundance varies over the solar cycle. Observations show a consistent rise and fall in helium levels that closely tracks solar activity, but with a delay that depends on wind speed. This lag is longer in faster solar wind, pointing to different origins or processes that affect how helium enters the wind. Notably, helium levels drop sharply and then recover just before solar minimum, possibly due to interactions between overlapping solar cycles.

Summary generated with ChatGPT based on my first-author publications for clarity and accessibility.