Discovery of Telescopes

By Dhruva
  • 3500 BCE

    Phoenicians

    When Phoenicians were cooking on sand around 3500BC, they discovered glass. But it took a few thousand years before glass was shaped into a lens for the first telescope. Lens that could change the magnification of objects were known in Europe at the end of the thirteenth century.

  • Hans Lippershey

    Hans Lippershey, a German-Dutch lensmaker once said that he wanted to make an instrument “for seeing things far away as they were nearby”. He was the first person to ever think of the telescope. The first telescope was used for spotting the army's enemy. It consisted of a biconvex lens placed about 40cm away from a biconcave lens.

  • Galileo Galilei

    On hearing about this new instrument, Italian physicist Galileo Galilei builds his own. He improved Lippershey’s design and using his new telescope the following year, he discovers the four largest moons of Jupiter, sunspots on the surface of the Sun, the phases of Venus and physical features on the Moon – such as craters! Galilei's telescope was a simple refractor telescope, using a plano-convex lens and a plano-concave eye lens in a tube. It magnified up to 30 times.

  • Johannes Kepler

    The German Johannes Kepler invented the form of the refracting telescope that is the basis for modern refractors. It has a convex eye lens. However, Kepler's telescope produced large inverted images with some chromatic distortions.

  • Sir Isaac Newton

    After studying the reflection of light through prisms, Sir Isaac Newton decides that the problem of chromatic distortion cannot be solved. He makes an improved version of the reflecting telescope. Instead of lenses, a curved mirror was used to gather in light and reflect it.

  • Bernhard Schmidt

    In 1930, Bernhard Schmidt a telescope using a spherical mirror, not a parabolical reflector, and a correcting lens at the telescope opening to compensate for spherical aberration; thus it is a combination reflector-refractor system.

  • Grote Reber

    Grote Reber, an American amateur ham-radio enthusiast, built the world's first radio telescope. Radio waves are also a part of the electromagnetic spectrum. A radio signal telescope is a large dish-shaped device that gathers and amplifies radio frequencies from space.

  • The Hubble Space Telescope

    Since 1990, the Hubble Space Telescope, run jointly by NASA and the European Space Agency, is orbiting the Earth at an altitude of 600km and capturing images from what scientists believe is the edge of our universe.