Telescope Functions

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Telescope Functions

• 1 Gather Light

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Gather Light
How much more light does the bigger telescope
gather? pr2
9x
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Telescope Functions
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Telescope Functions
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Telescope Functions
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Telescope Functions

• 1 Gather Light r2

2 Resolution
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Resolution
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Telescope Functions

• 1 Gather Light r2
• 2 Resolution q
• A aperture

k l
A
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Resolution
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Telescope Functions

• 1 Gather Light r2
• 2 Resolution q
• 3 Magnification

k l
A
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Refraction
smooth carpeted smooth
fast
slow
fast
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Refraction
fast slow fast
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Refraction
fast
slow
fast
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Refractors
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Refractors
Focus
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Refractors
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Reflectors
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Reflectors
Central Obstruction
12 Refractor 12 Reflector Which gathers more
light?
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tight space room moves around drinks spill
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very high
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closer to ground shorter telescope smaller dome
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multiple instruments easily changed at a moments
notice depends on size of instruments and size
of telescope
Nazysmith
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focus always in the same place one heavy
instrument
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Telescope Functions

• 1 Gather Light
• 2 Resolution
• 3 Magnification

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Resolution

• size
• chromatic aberration
• spherical aberration
• seeing

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Chromatic Aberration
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Acromats
Reduce Chromatic Aberration
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Spherical Aberration
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Parabolic Mirror
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Seeing
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Seeing
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Seeing
warm surface heats air hot air rises causes stars
to twinkle mountaintop observatory above
inversion layer no heat sources in observatory
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Seeing
Which is warmer on a sunny day, air or
water? Since air is warmer, how can cold water
warm air? stable air over water during
day daytime observatories surrounded by
water solar observatory
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Seeing
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Seeing
Which is warmer at night, air or water? Solar
observatories are terrible for nighttime
use. seeing/time beach cruise
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Resolution

• seeing
• adaptive optics

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Refractor
Reflector
shorter smaller housing spherical
aberration parabolic mirrors still cheaper UV
astronomy adaptive optics
gathers more light chromatic aberration acromats v
ery expensive
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Telescope Mount / Resolution

• altitude-azimuth
• stability
• equatorial
• tracking

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Alt-Az
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Alt-Az
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Alt-Az
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Alt-Az
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Equatorial
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Equatorial
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Equatorial
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Equatorial
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Equatorial
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Equatorial
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Equatorial
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Equatorial
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Equatorial Alt-Az
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Radio Telescopes

• resolution

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Radio Telescopes

• resolution

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Radio Telescopes

• resolution

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Radio Telescopes

• resolution

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Radio Telescopes

• resolution

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Radio Telescopes

• resolution

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Radio Telescopes

• resolution

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Radio Telescopes

• resolution

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Radio Telescopes

• resolution

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Radio Telescopes

• arrays
• interferometry

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Radio Telescopes

• arrays

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Instrumentation
image spectrum brightness
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Image
photochemical digital
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Photochemical

• glass plates
• exposure time
• processing time
• scanning time

• dark room
• chemicals
• disposal
• archives

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DigitalCCDCharge Coupled Device

• single chip
• exposure time
• download time

• liquid nitrogen
• archives
• maintenance

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Spectrum
Take Notes at Telescope Record Image Analyze
Image Later
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Brightness
Hipparchus magnitude
brighter than 1st
fainter than 6th
logarithmic Five magnitudes lower means one
hundred times as bright.
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Photometer
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Photometer
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Photometer
Light Pollution
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Photometer
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CCD
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