Ukichiro Nakaya (1900–1962) was a Japanese scientist who created the first artificial snowflake in 1936 and figured out how temperature and humidity affect snow crystal shapes — a result smmarized in the "Nakaya diagram." He studied ice in Greenland, wrote popular science essays for everyday readers (earning him the nickname "Japan's Carl Sagan"), and was a pioneer in making educational films. This article, written for his 125th birthday, covers his life, his science and his writing.

George Perkins Merrill, a Smithsonian scientist in the early 1900s, made discoveries about meteorites that still shape our understanding of the solar system's birth. Using microscopes to examine tiny spherical grains called chondrules, the building blocks of stony meteorites, he concluded they formed through multiple processes.. He also showed that meteorites record a history of alteration by heat and pressure over time. His laid groundwork for meteorite research for over a century.

A detailed history of the Max-Planck-Institut für Aeronomie (MPAe), including its research and deleopment.