Hubble’s constant

astrometry, Gaia space probe, European Space Agency - ESA, telescope, astrolabe, armillary sphere, trigonometry, Hipparchus, parallax effect, heliometer telescope, 61 Cygni, Astrographic Catalogue, Space Age, Milky Way galaxy, white dwarf stars, Kepler space telescope, Hubble's constant, quadrants, sextants, astronomy,

From Hipparchus to Gaia, the Story of Finding Our Place Among Billions of Stars