Helium [SEP] named after
created by nuclear fusion of hydrogen in stars.
Helium is named for the Greek Titan of the Sun, Helios. It was first detected as an unknown, yellow spectral line signature in sunlight, during a solar eclipse in 1868 by Georges Rayet, Captain C. T. Haig, Norman R. Pogson, and Lieutenant John Herschel, and was subsequently confirmed by French astronomer, Jules Janssen. Janssen is often jointly credited with detecting the element, along with Norman Lockyer. Janssen recorded the helium spectral line during the solar eclipse of 1868
Finally, the highest-energy particles observed by ACE are the galactic cosmic rays (GCRs), thought to be accelerated by shock waves from supernova explosions in our galaxy.
Science results Other findings from ACE.
Shortly after launch, the SEP sensors on ACE detected solar events that had unexpected characteristics. Unlike most large, 
shock-accelerated SEP events, these were highly enriched in iron and helium-3, as are the much smaller, flare-associated impulsive SEP events. Within the first year of operations, ACE found