Stellar diameter

Michelson used a 20-foot interferometer and a 100-inch telescope to measure the diameter of the star Betelgeuse. The diameter was calculated to be about 260 million miles, making it 300 times that of the Sun.
 Albert Abraham Michelson United States 1920 Stellar diameter

Michelson used a 20-foot interferometer and a 100-inch telescope to measure the diameter of the star Betelgeuse. The diameter was calculated to be about 260 million miles, making it 300 times that of the Sun.