Chapter 6: Telescopes Flashcards
What are the two most important properties of telescopes?
The telescopes light collecting area and its angular resolution.
What is a telescopes light collecting area?
A measure of how much light a telescope can collect at one time.
What is a telescopes angular resolution.
The smallest angle over which we can tell two dots are distinct.
What is a telescopes diffraction limit?
The angular resolution that a telescope could achieve if it were only limited by the interference of light waves.
What is a relfecting telescope?
A telescope that uses mirrors to reflect and gather light.
What is a refracting telescope?
A telescope that uses lenses to collect and focus light.
What is a spectograph?
An instrument that uses diffraction gratings or other devices to separate various colours of light into spectra, which are then recorded with a detector.
What does the information gained by a spectrum depend on?
Spectral resolution.
What is interferometry?
The technique of using multiple telescopes to increase angular resolution.
What are grazing incidence mirrors?
Mirrors that are designed to allow X-Rays to graze their surfaces. This allows X-Rays to be reflected without passing through the mirror.
