Telescope

A telescope is an optical instrument using lenses and/or curved mirrors to observe distant objects for both terrestrial applications and astronomy.

In 1608 a patent was submitted by Dutch spectacle maker Hans Lippershey for a refracting telescope. Galileo heard about it and, in 1609, built his own version, and made his telescopic observations of celestial objects. In 1668 Isaac Newton built the first practical reflecting telescope.

Physicist Brian Greene wrote: “The invention of the telescope and its subsequent refinement and use by Galileo marked the birth of the modern scientific method and set the stage for a dramatic reassessment of our place in the cosmos. A technological device revealed conclusively that there is so much more to the universe than is available to our unaided senses.”

The 20th century also saw the development of telescopes that worked in a wide range of wavelengths from radio to gamma-rays. The first radio telescope went into operation in 1937. Since then, a large variety of complex astronomical instruments have been developed.

Future
The Einstein Telescope (ET) is a third-generation gravitational wave observatory developed by research institutions in the European Union. It has 10 times the sensitivity of any previous instrument, which greatly increases the distance at which black hole collisions, neutron stars, dark matter, and other gravitational wave sources can be analyzed. It will also improve tests of Einstein's general theory of relativity.

Additionally, the previous generation of gravitational wave observatories only studied the Universe at a 10 billion light years distance. The Einstein Telescope is able to look even further back in time, to the cosmic "Dark Ages" – when the first stars and galaxies began to form.

25 December 2021
The James Webb Space Telescope was launched by NASA. With the the biggest mirror of any space-bound telescope ever launched and three decades in the making, it will use infrared imaging and peer far back in time to see some of the earliest objects to have formed just after the Big Bang. It will also investigate supermassive black holes, distant alien worlds, stellar explosions, dark matter, and more.

JWST will be traveling to an extra cold spot located 1 million miles from Earth, where the spacecraft will live out its life, giving the world’s astronomers an extremely powerful tool for the next 5 to 10 years.