(1850-1918) German physicist who made improvements to Guglielmo Marconi's system of wireless telegraphy; they shared the 1909 Nobel Prize for Physics. Braun also discovered crystal rectifiers (used in early radios), and invented the oscilloscope 1895.
Braun was born in Fulda, Hesse, and educated at Marburg and Berlin. He held academic posts at a number of German universities, ending his career as professor and from 1895 director of the Institute of Physics at Strasbourg.
In an attempt to increase the radio transmitter range to more than 15 km/9 mi, Braun devised a system in which the power from the transmitter was magnetically coupled (using electromagnetic induction) to the antenna circuit. He patented this invention 1899, and the principle of magnetic coupling has since been applied to all similar transmission systems. Later Braun developed directional antennas.
In 1874 Braun discovered that some mineral metal sulfides conduct electricity in one direction only. These were later used in the crystal radio receivers that preceded valve circuits.
Braun's oscilloscope was an adaptation of the cathode-ray tube. A laboratory instrument to study high-frequency alternating currents, it was the forerunner of television and radar display tubes.

(1910-1945) German mistress of Adolf Hitler. Secretary to Hitler's photographer and personal friend, Heinrich Hoffmann, she became Hitler's mistress in the 1930s and married him in the air-raid shelter of the Chancellery in Berlin on 29 April 1945. The next day they committed suicide together.

(1889-1971) US botanist, an early pioneer in recognizing the importance of plant ecology and conservation. Her book Deciduous Forests of Eastern North America 1950 describes the evolution of forest communities and their survival during periods of glaciation.
Born in Cincinnati, Braun studied geology and botany at the University of Cincinnati. She remained in academic positions at the university until 1948, becoming professor of plant ecology in 1946. She lived with her sister Annette Braun (1884–1978), an entomologist, and continued research work until the end of her life, the two setting up a home laboratory and an experimental garden.
Braun's work in ecology concentrated on the vegetation of a selected variety of habitats in Ohio and Kentucky. An early taxonomic study provided a detailed catalog of the flora of the Cincinnati region, which she then compared with that of the same region a century earlier. This approach became very influential for analyzing regional changes in flora over a period of time.
Braun also wrote and campaigned to save natural areas and to create nature reserves.

(1912-1977) German scientist responsible for Germany's rocket development program in World War II. He was technical director of the army rocket research center at Peenemunde and designed a number of rockets including the V2. He was taken to the US with his research team 1945 and, as director of the George C Marshall Space Flight Center In Huntsville, Alabama, became a prominent figure in the NASA space program.