| Year |
Information |
| 1906 |
Ejnar Hertzsprung establishes standard for a star's true brightness. |
| 1916 |
Karl Schwarzschild laid groundwork for the black hole theory. |
| 1923 |
Edwin Hubble proved that the Adromeda Nebula and other nebulas were far away galaxies. |
| 1925 |
By the year 1925, Hubble produced a classification system for galaxies. |
| 1926 |
The first liquid fueled rocket is launched by Robert Goddard |
| 1929 |
Edwin Hubble discovered that the universe is expanding. |
| 1930 |
Clyde Tombaugh discovered planet Pluto. |
| 1932 |
Karl Jansky detects first space radio ways. |
| 1938 |
Hans Bethe explained how stars generated energy. |
| 1942 |
Radio waves from the Sun are detected. |
| 1944 |
German Scientists develop the first rocket-powered ballistic missile. |
| 1948 |
The largest telescope in the world is completed in California. |
| 1957 |
Russia launches first satellite into space. |
| 1957 |
US launches first satellite into space four months after the Russians. |
| 1959 |
US and Russica launch probes to the Moon. |
| 1961 |
Russian astronaut, Yuri Gagarin becomes the first person to orbit the Moon. |
| 1963 |
Maarten Schmidt establishes that quasars are active galaxies. |
| 1966 |
Russian probe, Russian Luna 9, is the first successful landing on the Moon in January. |
| 1966 |
US lands Surveyor 1 on the Moon in May. |
| 1969 |
Neil Armstrong is the first person to step foot on the Moon. |
| 1971 |
Russia's first space station, Salyut 1 launches into orbit. |
| 1975 |
Russian probe, Venera 9, lands on Venus' surface. |
| 1977 |
NASA probe, Voyager 2, becomes first probe to visit Uranus and Neptune. |
| 1983 |
The first infrared satellite is launched. |
| 1990 |
The Hubble Space Telescope is launched into orbit. |
| 1998 |
The International Space Station construction begins. |