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(April 2017) (Learn how and when to remove this template message) </Td> </Tr> <P> This is for a timeline of space exploration including notable achievements and first accomplishments or major events in humanity's exploration of outer space . </P> <Table> <Tr> <Th> Date </Th> <Th> Event leading to space exploration </Th> <Th> Country </Th> <Th> Researcher (s) </Th> </Tr> <Tr> <Td> 1610 </Td> <Td> First telescopic observation of the night sky: discovery of Jupiter's moons, lunar craters and the phases of Venus . </Td> <Td> Republic of Venice </Td> <Td> Galileo Galilei </Td> </Tr> <Tr> <Td> 1687 </Td> <Td> Publication of the Philosophiæ Naturalis Principia Mathematica </Td> <Td> England </Td> <Td> Sir Isaac Newton </Td> </Tr> <Tr> <Td> 1813 </Td> <Td> First exposition of the rocket equation based on Newton's third law of motion: Treatise on the Motion of Rockets </Td> <Td> UK </Td> <Td> William Moore </Td> </Tr> <Tr> <Td> 1840 </Td> <Td> First clear telescopic photograph of another world: the Moon . </Td> <Td> United States </Td> <Td> John William Draper </Td> </Tr> <Tr> <Td> 1865 </Td> <Td> From the Earth to the Moon published . </Td> <Td> France </Td> <Td> Jules Verne </Td> </Tr> <Tr> <Td> 1898 </Td> <Td> The War of the Worlds published . This inspired Robert Goddard to investigate rocketry . </Td> <Td> UK </Td> <Td> H.G. Wells </Td> </Tr> <Tr> <Td> 1903 </Td> <Td> Inspired by the writings of Jules Verne, first serious work published that showed physical space exploration was theoretically possible: Исследование мировых пространств реактивными приборами (The Exploration of Cosmic Space by Means of Reaction Devices) </Td> <Td> Russia </Td> <Td> Konstantin Tsiolkovsky </Td> </Tr> <Tr> <Td> 1914 </Td> <Td> Goddard files for and is subsequently awarded U.S. patents on multistage and liquid - fueled rockets </Td> <Td> United States </Td> <Td> Robert H. Goddard </Td> </Tr> <Tr> <Td> 1919 </Td> <Td> Goddard's widely influential paper "A Method of Reaching Extreme Altitudes" discussed solid - and liquid - fueled rocketry </Td> <Td> United States </Td> <Td> Robert H. Goddard </Td> </Tr> <Tr> <Td> 000000001923 - 12 - 15 - 0000 15 December 1923 </Td> <Td> Die Rakete zu den Planetenräumen ("By Rocket into Planetary Space") self - published after its rejection as a doctoral thesis . </Td> <Td> Germany </Td> <Td> Hermann Oberth </Td> </Tr> <Tr> <Td> 1924 </Td> <Td> Society for Studies of Interplanetary Travel founded </Td> <Td> USSR </Td> <Td> Members include Konstantin Tsiolkovsky, Friedrich Zander, Yuri Kondratyuk </Td> </Tr> <Tr> <Td> 000000001926 - 03 - 16 - 0000 16 March 1926 </Td> <Td> Goddard launches the first liquid - fueled rocket </Td> <Td> United States </Td> <Td> Robert H. Goddard </Td> </Tr> <Tr> <Td> 1927 </Td> <Td> Verein für Raumschiffahrt (Society for Space Travel) formed; it includes many top European rocket scientists . </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> 1927 </Td> <Td> Завоевание межпланетных пространств (The Conquest of Interplanetary Space) discusses rocket mechanics and orbital effects including the gravitational slingshot </Td> <Td> USSR </Td> <Td> Yuri Kondratyuk </Td> </Tr> <Tr> <Td> 1928 </Td> <Td> Das Problem der Befahrung des Weltraums--der Raketen - Motor (The Problem of Space Travel--The Rocket Motor) discusses space travel and its potential uses for scientific experiments . </Td> <Td> Germany </Td> <Td> Herman Potočnik </Td> </Tr> <Tr> <Td> 1929 </Td> <Td> Oberth, with students including Wernher von Braun, launches his first liquid - fueled rocket </Td> <Td> Germany </Td> <Td> Hermann Oberth </Td> </Tr> <Tr> <Td> 1931 </Td> <Td> First German military liquid - fueled rocket engines developed </Td> <Td> Germany </Td> <Td> Walter Riedel </Td> </Tr> <Tr> <Td> 1933 </Td> <Td> Work begins on the Aggregate series of rockets which leads to the V - 2 rocket . </Td> <Td> Germany </Td> <Td> Wernher von Braun </Td> </Tr> <Tr> <Td> </Td> <Td> Group for the Study of Reactive Motion (GIRD) launches the first Soviet liquid - fueled rocket </Td> <Td> USSR </Td> <Td> Sergey Korolev (group leader), Friedrich Zander (designer) </Td> </Tr> <Tr> <Td> 1935 </Td> <Td> Graduate student Frank Malina under his professor Theodore von Kármán begins work on a sounding rocket </Td> <Td> United States </Td> <Td> Frank Malina </Td> </Tr> <Tr> <Td> 000000001935 - 11 - 11 - 0000 11 November 1935 </Td> <Td> The Explorer II balloon takes two people to 22,066 metres (72,395 ft), where they observe and photograph the curvature of the Earth . </Td> <Td> United States </Td> <Td> Albert W. Stevens and Orvil A. Anderson </Td> </Tr> <Tr> <Td> 000000001944 - 06 - 20 - 0000 20 June 1944 </Td> <Td> V - 2 Rocket (MW 18014): First man - made object to cross what would later be defined as the Kármán line and hence first spaceflight in history . </Td> <Td> Germany </Td> <Td> Wehrmacht </Td> </Tr> <Tr> <Td> 000000001946 - 05 - 10 - 0000 10 May 1946 </Td> <Td> First space research flight (cosmic radiation experiments) </Td> <Td> United States </Td> <Td> captured and improved V - 2 rocket </Td> </Tr> <Tr> <Td> 000000001946 - 05 - 22 - 0000 22 May 1946 </Td> <Td> First U.S. - designed rocket to reach edge of space (80 km (49 mi)) </Td> <Td> United States </Td> <Td> WAC Corporal </Td> </Tr> <Tr> <Td> 000000001946 - 10 - 24 - 0000 24 October 1946 </Td> <Td> First pictures of Earth from 105 km (65 mi) </Td> <Td> United States </Td> <Td> V - 2 </Td> </Tr> <Tr> <Td> 20 February 1947 </Td> <Td> First animals in space (fruit flies) </Td> <Td> United States </Td> <Td> V - 2 </Td> </Tr> <Tr> <Td> 22 July 1951 </Td> <Td> First dogs in space (Dezik and Tsygan) </Td> <Td> USSR </Td> <Td> R - 1 </Td> </Tr> </Table> <Tr> <Th> Date </Th> <Th> Event leading to space exploration </Th> <Th> Country </Th> <Th> Researcher (s) </Th> </Tr>

When did space exploration began in the us