Telescopes Flashcards
What is a telescope
A device that collects light and brings it into focus
Does a telescope use lenses or mirrors
Either
What are the two basic telescope types
Refractor or reflector
What is refraction
When Light bends when it encounters matter
What are rainbows
Sunlight when it gets refracted by water droplets
What are problems with refracting telescopes
Very hard and expensive to make, chromatic aberration, large lenses are heavy, both sides must be shaped perfectly
What is chromic aberration
Different wavelengths of light are focused at slightly different points
What is the worlds largest refracting telescope
Heroes observatory
What is reflecting telescopes coated in
Aluminum, silver or gold
What is telescope resolution
Measure of how small an angle a telescope can distinguish
Issues with telescope resolution
When light passes through a telescope, it experiences a wave of interference (diffraction)
When does diffraction increase
With longer wavelength and smaller apertures
Where is seeing best
On mountain tops with unvarying high pressure systems
How to eliminate seeing
Speckle, take long quick exposures of the same object and align them
What is adaptive optics
Using deformable mirrors we can adopt the shape to account for distortions
Best sites for telescopes
Clear weather, dry, little light pollution, little turbulence
Where are UV telescopes
In space
Where are I fared telescopes
As little atmosphere as possible
Where are radio telescopes
The ground
Radio telescopes must be ___ in size
Large bc the wavelength is so long
Where are X-ray and gamma ray telescopes located
In space
Which electromagnetic radiation creates particle showers
Gamma rays
What are filters used for
To specifically analyze parts of the electromagnetic spectrum ( red or blue light)
What are spectrometers
Diffraction grating, light passing through many slits gets dispersed into a spectrum
