 Around 2002, Joseph M. Davila and Barbara J. Thompson at NASA's Goddard Space Flight Center adopted the term in their preparations of what became known as the International Heliophysical Year (2007-2008), following 50 years after the International Geophysical Year; in adopting the term for this purpose, they expanded its meaning to encompass the entire domain of influence of the Sun.As an early advocate of the newly expanded meaning, George Siscoe offered the following characterization