Intro

Objective 04/2/2013Compare refracting and reflecting telescopes.

Have you ever bent or slowed down light? How?

Telescopes

• Telescope • An instrument that collects electromagnetic radiation from the sky and concentrates it for better observation– Optical telescopes– Nonoptical telescopes

• Optical Telescopes • Collects visible light and focuses it for observation

• Most have two lenses– Objective lens: collects

light and forms an image– Eyepiece: magnifies the

image

• Refracting Telescopes • A telescope that uses a set of lenses to gather and focus light from a distant object

• Refract = bend• Negative:– Images cannot be

perfectly focused– If lens is too big it

distorts image

• Reflecting telescope • A telescope that uses a curved mirror to gather and focus light from distant objects

• Reflect = bounce back• Positive:

– Large mirrors can collect more light

– Flaws in glass do not affect light

– Mirrors can focus all light perfectly

• Linking Reflecting Telescopes

• Atmosphere

• Space

• Can link two or more large telescopes to see further into space

• Air, moisture, light pollution can cause image to blur and shimmer

• Best place to have a telescope!

Telescopes

Telescopes

Saturn Aurora

Supernova

• Eagle Nebula (full)

Crab Nebula

Star Cluster

Galaxy Collision

Electromagnetic spectrum • All the frequencies or wavelengths of energy

• Nonoptical Telescopes • Detect radiation that cannot be seen by the human eye

• Most electromagnetic waves are blocked by our atmosphere, so most nonoptical telescopes are placed in space

Radio Telescope

Radio Telescope

Infrared Telescope

Infrared Telescope

X Ray Telescope

X Ray Telescope

Gamma Ray Telescope

Gamma Ray Telescope

What can we draw here to represent “Radio waves”?

Awesome! Now, fill in the rest of these boxes with examples of the EMS. Use page 561 in the Red Book for help

Green Bank Telescope (West Virginia)

Arecibo Telescope, Puerto Rico

New Mexico

Radio WavesX-Ray

Sun in Ultraviolet Light

Outro

Objective 04/2/203Compare refracting and reflecting telescopes.

Why is having a telescope in space better than having one on Earth?