Telescopes

For all the colors of light

Similar to the telescopeGalileo used to see the moonsof Jupiter, the moon, and Venus

Uses Lenses!

Galileo’s telescopes

150 foot long refracting telescope!!

Built by Johannes Hevelius

An old Refractor with guide scope

But lenses absorbed some of the faint light, caused the colors to focus at different points, and could only be made to a certain size. The largest is the 40 inch refracting telescope at

Yerkes observatory. Glass bigger than that would not be able to hold itself up!

SO…

Designed byIsaac Newton –originally designed withno secondary mirroror eyepiece. You justput your eye near thetop and looked in!

Eyepieces and camerasmade it all easier to use.

Early Newtonian telescope

You could make a glass mirror a LOT bigger than 40 inches – and it didn’t distort the light.

A 5 meter mirror (the Hale telescope at Mt. Palomar) was the largest for a long time.

Currently, the largest Single Piece of glass telescope is 8 meters (Subaru and others)

People were still unsatisfied – and came up with the idea of putting together a number of carefully made mirror segments, controlled by computer to stay extremely accurate.

Keck I was a 10 meter segmented telescope – and the current largest.

The addition of Keck II (another 10 meter telescope) makes a very large telescope array.

The deeper the curve, the closer in the focal point.

Optical telescopes have farther focal points, Radio telescopes have shorter ones.

To make a shortertelescope, they puta secondary mirror infront to reflect it backthrough the main mirror.

Most large telescopesuse this design.

Herschel’sNewtonianstyletelescope.

24 inch Schmidt at Palomar

Used for takingimages of solarsystem objects – planets and comets.

Optical Telescopes are on Mountain tops Away from the lights of the cities, above the clouds, above

the weather,

Radio Telescopes are in Valleys Avoiding the radio noise made by cities, cars, and radio

stations

X-ray and Gamma ray telescopes are in space X-rays and Gamma rays can’t get through the atmosphere!

Radio Telescopes

Seeing one kind of invisible light

Built by Grote ReberNow at NRAO-Greenbank

First Radio Telescope

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The Big Ear - OSU(dismantled)

Developed by John Kraus

Jodrell Bank - UK

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NRAO – Greenbank, WV

The 40 foot telescope used byteachers and a few others. Including Mr.B

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100 MinGermany

World’s Largest - Arecibo

VLA – Socorro, NM

Optical Telescopes

Visible and Infrared

On the Ground and in Space

Yerkes – 40 inch refractor

Hooker – Mt Wilson

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Hale – Mt. Palomar

200 inch5 meter

solid glassmirror

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Keck I and II – Mauna Kea

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Subaru –Mauna Kea

HST

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IRAS

InfraRedAstronomySatellite

IRTF – Mauna Kea

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Spitzer

Next generationIR telescope inspace.

Millimeter and Sub-millimeter Telescopes

JCMT – Mauna Kea

JamesClerkMaxwellTelescope

Millimeterand sub-millimeter

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Gamma Ray Telescopes

Really High Energy!!!

Looking for Cherenkov Radiation in the atmosphere to prove gamma rays are coming in.

Gammam - Haleakala

Whipple – Gamma-ray telescope

X-Ray Telescopes

Chandra X-Ray Telescope

X-Ray Telescope (HEAO)

Grazing Incidence X-Ray Mirror

Other interesting Telescopes

Kitt Peak – Solar Telescope

Amanda – Looking through the Earth for Neutrinos

300 foot – NRAO - Before

300 foot – NRAO - After

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DisclaimerAloha

I put together these power points for use in my science classes.You may use them in your classes.

Some images are public domain, some are used under the fair-use provisions of the copyright law, some are mine. Copyright is retained by the owners!

Ted Brattstrom