reflective refractive spectro scopy space large telescopes how optical works $ 200 $ 200$200 $ 200 $...
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ReflectiveRefractiv
eSpectroscopy
SpaceLarge
telescopes
How Optical works
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$600 $600 $600 $600 $600 $600
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$200
Draw a convex lens
$400
The lens are made of glass and the larger they are , the more heavy and more flawed
they can be.
Why are refractive telescopes usually smaller than
reflective?
$600
Reflective
A telescope with a convex mirror and an eyepiece on the
side is a
$800
They gather more light and have better resolution
Why might you want a larger scope than a smaller one?
$1000The Cassegrain needs a hole drilled in the
middle of the primary mirror for the eyepiece and its secondary mirror in convex
rather than flat.
Why is a Newtonian reflector easier to build than a Cassegrain?
$200
Reflection
The process when Photons bounce off a polished surface
$400
Refraction
The tendency of a wave to bend as it passes from one transparent medium to another is
$600
Chromatic aberration
Fuzziness in your lens is caused by
$800
CCD’s are faster at capturing light so shorter exposure time. The image is digital, no wait time to be developed. The image is stored on computers, so can be transmitted
via the Internet
Why is a CCD better than photography for telescopes?
$1000Reflectors use a concave mirror to reflect
light back to a focus, refractors use a convex lens to bend light to a focus.
Compare how a reflector makes an image versus a
refractor
$200
radio
The lowest energy EM radiation is
$400
Most information we receive about the Universe comes in EM waves, especially
light. We can get temperature, compostion and motion from a spectrum
Why do astronomers relie on spectroscopy?
$600
An emission spectrum of bright lines (Kirchoff’s 2nd law)
A nebula is a low density cloud of hot gas, what is its
spectrum?
$800
Describe two ways that light is separated out into its component colors for
spectroscopy
Using a prism or diffraction gratings where thin slits diffract light.
$1000
1st Law: dense hot objects create a continuous spectrum
2nd law: low density gas gives off bright emission lines
3rd law: cool thin gas creates dark lines in the spectrum
Describe Kirchoff’s three laws
$200
Turbulence or star twinkling
Adaptive optics help correct
$400
NO.
Is it true that the HST is the Largest telescope ever built?
$600
Infrared and Ultraviolet
Besides visible light, Hubble does work in what two other
wavelengths?
$800
The Chandra uses which kind wavelength to form images?
X-rays
$1000
Adaptive optics are for poor visibility due to atmospheric blurring, Hubble is in space!
Why doesn’t the Hubble Telescope need adaptive
optics?
$200
To collect light and bring it to focus
The primary purpose of telescopes is to
$400
What is the downside of radio telescopes?
Poor resolution due to the large wavelength
$600
Interferometry
Using multiple telescopes to enhance resolution via
computers is called
$800
The atmosphere blocks most UV radiation
Why is UV astronomy hard to do from the ground?
$1000
Name three ways that radio telescopes have an advantage
over optical telescopes.
Can be used in daytime and night. Less effected by weather/ Allow us to see
objects at different wavelength than visible light.
$200
To get above the influences of our atmosphere
Why do we put telescopes in space?
$400
resolution
The ability to distinguish between two adjacent objects is
$600
The resolution is 2x’s as sharp and can now detect 4x’s as dim of objects.
How does doubling the diameter effect resolution and
light?
$800Stars do not twinkle in space but as they pass
through our atmosphere the light is shifted by turbulence.
Why do stars appear to twinkle?
$1000
The object has already flipped over since the eyepiece lies behind the focal point.
Why is the image in a telescope eyepiece inverted?