the itty bitty telescope and sidewalk radio astronomy

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The Itty Bitty Telescope andThe Itty Bitty Telescope andSidewalk Radio AstronomySidewalk Radio Astronomy

Sue Ann HeatherlyNational Radio Astronomy Observatory

www.nrao.edu

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What is radio astronomy?What is radio astronomy?

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Radio Waves are NOT Radio Waves are NOT sound!sound!

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A light wave is a light wave, no matter how A light wave is a light wave, no matter how long...long...

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Radio TelescopeRadio Telescope

Optical TelescopeOptical Telescope

Nowadays, there are more Nowadays, there are more similarities between optical similarities between optical and radio telescopes than and radio telescopes than ever before.ever before.

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Optical and radio astronomy can be done from the ground!Optical and radio astronomy can be done from the ground!

Credit: Windows to the Universe, thence to NASA/STSCI/JHU

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A A Tour Tour of the of the Radio Radio SkySky

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Gas Spectra

Neon

Sodium

Hydrogen

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Building an Building an Itty Bitty TelescopeItty Bitty Telescope

GBTGBTIBTIBT

David Fields with kids in MemphisDavid Fields with kids in Memphis

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RV Kit--$60 from EbayRV Kit--$60 from Ebay

12 GHz satellite dish combined with a signal meter 12 GHz satellite dish combined with a signal meter becomes a radio telescope!becomes a radio telescope!

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Constructing the dishConstructing the dish

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Realigning the mounting sleeveRealigning the mounting sleeve

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Mounting Sleeve SchematicMounting Sleeve Schematic

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Mounting the DishMounting the Dish

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Finishing UpFinishing Up

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DetectorsDetectorsproduce an audible tone which increasesproduce an audible tone which increases

in pitch when you detect radio signals.in pitch when you detect radio signals.

Most expensive ($99). Has built Most expensive ($99). Has built in battery.in battery.

Mid-priced ($50), needs a power Mid-priced ($50), needs a power supply.supply.

Cheapie! ($15), needs a power Cheapie! ($15), needs a power supply.supply.

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Making the power supplyMaking the power supply

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Preparing the CoaxPreparing the Coax

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Assembling the battery packAssembling the battery pack

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Battery Pack SchematicBattery Pack Schematic

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Done!Done!

Using Using the the IBTIBT

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The Sun emits radio waves!The Sun emits radio waves!

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You emit radio waves!You emit radio waves!

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Geostationary satellites ( Can you find 0Geostationary satellites ( Can you find 0° dec?)° dec?)

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Trees (the ground, buildings, anything with a Trees (the ground, buildings, anything with a temperature) emit radio waves!temperature) emit radio waves!

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Questions?Questions?

sheather@nrao.edu