Beyond the Solar System: Exploring Galaxies, Black Holes, Alien Planets, and More; A History with 21 Activities

Beyond the Solar System: Exploring Galaxies, Black Holes, Alien Planets, and More; A History with 21 Activities — page 3
1926 Robert Goddard launches the first liq uid fueled rocket paving the way for space exploration 1927 Robert Atkinson and Fritz Houtermans determine that stars are fueled by nuclear fusion 1929 discovers that the universe is expand Edwin ing Hubble 1931 Georges Lemaitre suggests the uni verse began in a huge explosion the Big Bang 1932 Jansky discovers cosmic Karl radiowaves 1933 Fritz Zwicky discovers evidence of dark matter 1957 World's first satellite Sputnik 1 orbits Earth 1963 Maarten Schmidt discovers quasars 1965 Arno Penzias and Robert Wilson dis cover cosmic microwave background