Lecture

Concept of a Telescope

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Description

This lecture introduces the concept of telescopes, explaining the principle behind them and the different types such as refracting and reflecting telescopes. It covers examples of historical telescopes, various designs, and components like lenses and mirrors. The lecture also discusses the resolution of telescopes, including factors like diffraction, aberration, and atmospheric blurring, as well as the use of interferometers to achieve high angular resolutions.

In MOOC

The Radio Sky II: Observational Radio Astronomy

The first part of the course introduces the different types of telescope technologies available to astronomers, with a particular focus on single-dish radio telescopes and radio interferometers. Optical, UV, X-ray, Gamma, neutrino, and gravitational wave telescopes will also be briefly covered, as well as a foray into Search for Extraterrestrial Intelligence. We, then, dive deep into the principles of observational radio astronomy, covering the observables (flux, luminosity, brightness temperature), and th

Official source

Ontological neighbourhood

Physics

Optics: Geometrical optics

Astronomy

Astrophotography: Topics in astrophotography

Related concepts (32)

Telescope

A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally it was an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects – an optical telescope. Nowadays, the word "telescope" is defined as wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors.

Reflecting telescope

A reflecting telescope (also called a reflector) is a telescope that uses a single or a combination of curved mirrors that reflect light and form an . The reflecting telescope was invented in the 17th century by Isaac Newton as an alternative to the refracting telescope which, at that time, was a design that suffered from severe chromatic aberration. Although reflecting telescopes produce other types of optical aberrations, it is a design that allows for very large diameter objectives.

Optical telescope

An optical telescope is a telescope that gathers and focuses light mainly from the visible part of the electromagnetic spectrum, to create a magnified image for direct visual inspection, to make a photograph, or to collect data through electronic s. There are three primary types of optical telescope: Refracting telescopes, which use lenses and less commonly also prisms (dioptrics) Reflecting telescopes, which use mirrors (catoptrics) Catadioptric telescopes, which combine lenses and mirrors An optical telescope's ability to resolve small details is directly related to the diameter (or aperture) of its objective (the primary lens or mirror that collects and focuses the light), and its light-gathering power is related to the area of the objective.

Refracting telescope

A refracting telescope (also called a refractor) is a type of optical telescope that uses a lens as its objective to form an image (also referred to a dioptric telescope). The refracting telescope design was originally used in spyglasses and astronomical telescopes but is also used for long-focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures.

Angular resolution

Angular resolution describes the ability of any such as an optical or radio telescope, a microscope, a camera, or an eye, to distinguish small details of an object, thereby making it a major determinant of . It is used in optics applied to light waves, in antenna theory applied to radio waves, and in acoustics applied to sound waves. The colloquial use of the term "resolution" sometimes causes confusion; when an optical system is said to have a high resolution or high angular resolution, it means that the perceived distance, or actual angular distance, between resolved neighboring objects is small.

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