On 24 April 1990, the space shuttle Discovery launched, carrying five astronauts and the Hubble Space Telescope, a space-based observatory. The crew placed it in orbit on 25 April 1990.
The Hubble Space Telescope orbits 340 miles above Earth, free of atmospheric distortion.
When Hubble was launched, the age of the universe was known to be somewhere between 10-20 billion years old. By examining a certain class of stars that can be used to define distance, Hubble was able to help narrow that broad figure down to approximately 13.8 billion years, a number now used to understand the timeline and development of stars, galaxies and more.
Hubble has uncovered supermassive black holes lurking in the hearts of galaxies and helped map the presence of elusive dark matter around galaxy clusters. But one of its strangest discoveries was the revelation that the expansion of the universe is speeding up, driven by the presence of a still-unidentified and previously unknown “dark energy.” With its ability to bring pristine images of the universe to Earth, Hubble has often shown humanity how much it has still to learn about the cosmos.
[In paper Astronomical Advantages of an Extra-Terrestrial Observatory, Spitzer] described a telescope that would observe wavelengths of light not easily seen by ground-based telescopes. Beyond the limitations of Earth’s atmosphere, a space telescope could get higher quality images and see further into unimagined parts of space.
After the Soviet Union launched Sputnik 1, Congress passed, and President Eisenhower signed, the Space Act, creating the National Aeronautics and Space Administration (NASA) effective 01 October 1958.
Funding for the Hubble Space Telescope began in 1977.
Twenty years before the US launched Hubble, the People’s Republic of China became the fifth nation to place a satellite in orbit around the earth. It was based on the Dongfeng 3 ballistic missile and transmitted the national anthem of Communist China, The East is Red. China celebrates Space Day each 24 April.
The first four nations to launch a satellite in orbit:
- USSR (Sputnik, 04 October 1957)
- USA (Explorer-I, 31 January 1958)
- France (Astrix-1, 26 November 1965)
- Japan (Osumi 5, 11 February 1970)
- China (DFH-1, 24 April 1970)