Telescopes For all the colors of light

Similar to the telescope Galileo used to see the moons of Jupiter, the moon, and Venus Uses Lenses!

Galileos 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 by Isaac Newton – originally designed with no secondary mirror or eyepiece. You just put your eye near the top and looked in! Eyepieces and cameras made it all easier to use.

Early Newtonian telescope

You could make a glass mirror a LOT bigger than 40 inches – and it didnt 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 shorter telescope, they put a secondary mirror in front to reflect it back through the main mirror. Most large telescopes use this design.

Herschels Newtonian style telescope.

24 inch Schmidt at Palomar Used for taking images of solar system 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 cant get through the atmosphere!

Radio Telescopes Seeing one kind of invisible light

Built by Grote Reber Now at NRAO- Greenbank First Radio Telescope *

The Big Ear - OSU (dismantled) Developed by John Kraus

Jodrell Bank - UK *

NRAO – Greenbank, WV The 40 foot telescope used by teachers and a few others. Including Mr.B *

100 M in Germany

Worlds Largest - Arecibo

VLA – Socorro, NM

Optical Telescopes Visible and Infrared On the Ground and in Space

Yerkes – 40 inch refractor

Hooker – Mt Wilson *

Hale – Mt. Palomar 200 inch 5 meter solid glass mirror *

Keck I and II – Mauna Kea *

Subaru – Mauna Kea

HST *

IRAS InfraRed Astronomy Satellite

IRTF – Mauna Kea *

Spitzer Next generation IR telescope in space.

Millimeter and Sub-millimeter Telescopes

JCMT – Mauna Kea James Clerk Maxwell Telescope Millimeter and sub- millimeter *

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 *

Disclaimer Aloha 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