Awards presented at the Spring Meeting: Seventeenth Presentation: James B. Macelwane Award to Thomas E. Holzer in recognition of significant contributions to the geophysical sciences by a young scientist of outstanding ability

Abstract

Until fairly recently the solar wind was regarded as a roughly spherically symmetric outflowing gas driven by the high temperatures in the solar corona. Then, beginning about six years ago, evidence was found that at least some of high‐velocity solar wind streams—and perhaps a substantial fraction of the total mass flux—originate in the so‐called coronal holes, regions of lower temperature and density. It was difficult to reconcile how the enhanced fluxes could be supplied by such low‐density regions. Tom Holzer recognized that the rapidly expanding area of the streamlines above coronal holes due to the open magnetic field line geometry would substantially change the nature of the flow from these regions. Multiple critical points for the flow could occur leading to high expansion velocities and large particle fluxes. For this insight into the generation and expansion of the solar wind, and for other significant contributions in solar system and interstellar physics, Tom Holzer is one of this year's recipients of the James B. Macelwane award.