of The first telescopeKnown as a refracting telescope, this was made by a Dutch optician in the early 17th century. It had two lenses, a convex lens attached to the end of the telescope and a concave lens for the eyepiece. These telescopes were primarily used for land surveys and military operations. Italian astronomer Galileo Galilei was one of the first to point such a telescope at the sky.
German astronomer Johannes Kepler improved on the convex-concave design by using a pair of convex-concave lenses. The advantage was a wider field of view and higher magnification, but the images appeared upside down. Still, telescope manufacturers who used Kepler’s design were able to achieve magnifications of 100 times. With a 150-foot long telescopeHowever, such long tubes were vulnerable to wind and weather and were not very effective.
Sir Isaac Newton was Reflectionor curved mirrors, captured more light and avoided the distorting prismatic effect called chromatic aberration that occurs when light passes through a lens.
For over two centuries, the size, materials and quality of mirrors have continued to increase, as have the size of telescopes, culminating in the space age with the emergence of space telescopes, for example. Hubble and James WebbIt eliminated interference from the Earth’s atmosphere and, thanks to James Webb, we were able to see farther into space than ever before. Scouting some of the first galaxies It formed after the Big Bang over 13 billion years ago.
Currently, NASA has several space telescope projects underway, including: Nancy Grace Roman Telescope and Habitable World Observatory.
1609: The refracting telescope
Inspired by Dutch and Danish telescope builders, Galileo built his own telescope in 1609. His first telescope had a magnification of 3x. The design was subsequently improved, and the final telescope could magnify objects up to 30x.
Fortunately, Galileo was not only a gifted astronomer, but also a talented artist, and was able to capture detailed images of the cosmic objects he saw through his lens. This sketch of the moon revealed moon mountains and craters that had never been seen or thought of before.
1672: Sir Isaac Newton’s reflecting telescope
When light passes through glass it is separated into colour bands (ROYGBIV). This caused chromatic aberration in refracting telescopes which affected the quality of the image. To overcome the prism effect, Sir Isaac Newton built a reflecting telescope which used curved mirrors instead.
Laurent Cassegrain In 1672 he improved on Newton’s design, using a concave primary mirror and a convex secondary mirror to reflect light through a hole in the primary mirror to the eyepiece, achieving a long focal length in a compact tube.
1789: Herschelian Telescope
Sir William Herschel’s telescope was a reflecting design with a large primary mirror and an eyepiece placed off-axis so as not to obstruct the light path, which allowed for a larger mirror and therefore greater light-gathering power.
Herschel discovered a new planet with one of his telescopes and named it. Georgian Sidas It was named after King George III. The planet was later named Uranus.
Herschel’s drawing of a nebula, published in 1912 in “The Scientific Papers of Sir William Herschel” by the Royal Society and the Royal Astronomical Society, London.
1900: The Great Telescope at the Paris Universal Exhibition
This 57-metre reflecting telescope is more than half the length of a football field and was built by Paul Gautier for the Paris Universal Exhibition in 1900. The mirror had a diameter of 1.25 metres.
1917: Hooker Telescope
Mount Wilson Observatory’s Hooker Telescope, designed by George Ellery Hale, had a 100-inch mirror and was the largest telescope in the world at the time. It led to major advances in the study of galaxies and nebulae.
Edwin Hubble used the Hooker Telescope from the 1920s onwards, paving the way for the understanding that the universe is much larger than our galaxy and the Big Bang theory.
1990: Hubble Space Telescope
Built by NASA and the European Space Agency (ESA) Hubble Space Telescope is a space-based reflecting telescope with a 2.4-meter diameter mirror. It operates in Earth’s atmospheric orbit. During its initial operation, it provided unprecedented clarity and detail in observations of the universe.
NASA expects the telescope to remain operational through the late 2020s.
2021: James Webb Space Telescope
In collaboration with NASA, ESA and the Canadian Space Agency (CSA), James Webb Space Telescope It is an advanced space-based reflecting telescope with a segmented mirror measuring 6.5 meters in diameter.
It operates in the infrared spectrum, allowing it to observe distant galaxies, exoplanets, and other astronomical phenomena with extremely high sensitivity.
The Webb Telescope orbits the Sun near the second Sun-Earth Lagrangian point (L2), one million miles from Earth.
