1905: The Wright brothers sign a contract for one million francs with Frenchman Arnold Fordyce for the sale of a powered flying machine capable of flying a nonstop distance of 31 mi. When contingent of French government officials come to Dayton in April 1906 to change the agreement by seeking exclusivity for one year, the idea is dropped; for their trouble, the Wrights received 25,000 francs (then about US $5,000), the first money they earn from flying.
1924: Edwin Hubble announces the existence of other galaxies.
1947: The prototype of the second Mikoyan Type S fighter, an early version of the MiG-15, makes its first flight; it has an imported Rolls-Royce Nene 2 jet engine.