Hubble Space Telescope, 25 years revolutionizing astronomy
The first Hubble Space Telescope, which revolutionized astronomy and our vision of the universe with spectacular images of distant galaxies generated by it, is celebrating its 25th anniversary in space this week. "Hubble has changed the way humanity looks at the universe and sees its place in it, " says astronomer Jennifer Wiseman, a telescope scientist at Nasa's Goddard Center in Greenbelt, Maryland.
"This telescope has shown us that the cosmos has changed over time; that stars produce all the elements necessary for life and planet formation, " he continued in an interview with AFP in the Hubble control room. Since it was launched on April 24, 1990 by the Space Shuttle Discovery, Hubble orbits the Earth at 570 km altitude.
The telescope had its setbacks in early childhood, but it was fully operational three years after its deployment. The concavity of its main mirror had a flaw that caused a spacecraft to be sent to install a correction mechanism in a very delicate operation carried out in 1993.
It was after this that Hubble, a real-time machine dedicated to exploring the depths of space, began to transmit striking images of supernovae, cataclysmic explosions marking the death of a star and other celestial bodies. One of his most famous photos shows gigantic columns of interstellar gas and dust 6, 500 light-years from Earth in the Eagle Nebula, which is named "Pillars of Creation."
The 11-ton telescope is named after one of the pioneers of astronomy, Edwin Powell Hubble (1889-1953), and is a collaboration between NASA and the European Space Agency (ESA).
Hubble Findings
Hubble also revealed black holes in the heart of galaxies whose existence hitherto science could only suppose. He also made a million images of celestial bodies, some of which were at the ends of the cosmos, which allowed astronomers to more accurately calculate the age of the universe: about 13.8 billion years.
Thanks to all these images, far sharper than those obtained by the most powerful terrestrial telescopes, astrophysicists were able to confirm in 1998 that the expansion of the universe is accelerating. This discovery earned the Nobel Prize in Physics in 2011 for two Americans. This acceleration is the result of a mysterious force called dark energy, which would make up about 70% of the universe.
The rest of the cosmos is made up of 5% visible matter and 27% dark invisible matter, whose presence is manifested by its gravitational effects on celestial bodies. Other Hubble findings include the detection of the first organic molecule in the atmosphere of a planet orbiting a distant star in our galaxy, the Milky Way. In addition, the telescope concluded that planet formation is relatively common.
More recently, the venerable telescope has allowed us to advance our knowledge of the solar system. NASA recently announced that Hubble has detected a large underground saltwater ocean on Ganymede, Jupiter's largest moon - a discovery that provides clues to the search for extraterrestrial life in our vicinity.
True star of astronomy, "Hubble has played a very important role in instilling in our planet's inhabitants a sense of wonder at the universe we live in, " in the words of astronomer Wiseman. She also said she was convinced that Hubble still has many years to go. It should coexist with its successor, the James Webb infrared space telescope, which will be launched in 2018 and will be a hundred times more powerful. According to NASA astronomer Matt Greenhouse, "Webb could revolutionize astronomy once again."
By Jean-Louis Santini - Greenbelt, United States
Via InAbstract
