Planetary Society logo
  • “Exploration is in our nature.” - Carl Sagan

Edwin Hubble’s VAR! plate

Edwin Hubble’s VAR! plate
Edwin Hubble’s VAR! plate Edwin Hubble’s original glass photographic plate of the Andromeda Nebula, known as the VAR! plate, was on display at Carnegie’s Hale Library in Pasadena, California. Hubble took the image with the 100-inch Hooker Telescope at Mt. Wilson Observatory on the night of Oct. 5, 1923. He first marked one star with an “N” because he thought it was a nova, then crossed it out and wrote “VAR!” when he realized it was a Cepheid variable star. Using Henrietta Swan Leavitt’s discovery that these stars can reveal cosmic distances, Hubble showed that Andromeda is a separate galaxy far beyond the Milky Way. Sarah Al-Ahmed / The Planetary Society. Plate courtesy of Carnegie Science.