Remembering Frank Shu: A Pioneer in Astrophysics.

Chinese American astrophysicist Frank Hsia-San Shu, known for his contributions to the understanding of galaxies and star formation, has passed away at the age of 79. Shu was awarded the Shaw Prize in astronomy in 2009 and authored two widely consulted textbooks. Later in life, he investigated energy technologies to combat the climate crisis. Shu's work on density-wave theory allowed predictions of spiral-galaxy properties to be derived from first principles and was used to study the gravitational stability and structure of many astrophysical objects.