Observing

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Observing
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Next Tuesday

• Well meet at the observatory even if it is
  cloudy
• If the weather is really bad (a foot of snow or
  something) Ill send an email changing the
  meeting place, but otherwise

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Observatory location
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Observatory Location
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Telescopes

• Reflector
• 24-inch (60-cm) mirror
• Refractor
• 6 inch (15-cm) achromatic lens

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24-inch
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Ritchey-Chretien

• A special kind of cassegrain telescope
• Gives good wide field images (but our CCD field
  of view will be limited to 11 x 11 arcmin)

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6-inch
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What to observe?
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A BL Lac Object
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• BL Lac objects are one of the family of active
  galactic nuclei, a group which includes quasars
  and Seyfert galaxies, among others

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Long term light curve
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Makarian 421
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Reading assignment

• Read the section on Makarian 421 on the AAVSO web
  page
• Check the web/library for further info on BL Lac
  objects
• Give me (at the next class) a one page writeup on
  what is believed to cause the brightness changes
  of BL Lac objects (be sure to express this in
  your own words)

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Other possibilities

• Galaxies

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Star Clusters

• M67

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Gaseous Nebulae

• M42