Tools of Modern Astronomy

Tools of Modern Astronomy

Chapter 21 Section 1

Pages 716-718

Chapter 21 Section 1

Pages 716-718

• Main function- is to collect and focus different types of electromagnetic radiation.

Telescopes

• Refracting • Reflecting

• Uses two convex lenses (thicker at the edges) to gather large amounts of light and focuses it into a small area.

• 1609- Galileo used one to look at the sky.

• The larger the lens the more light it can collect

Refracting Telescope

Refracting Telescope

Reflecting Telescope•Uses a mirror instead of an objective lens.•Focuses large amounts of light into a small area.•1668- Newton build the first.•Today, this is the largest visible telescope.

Reflecting Telescope

• Used to detect radio waves

• Most have a curved surface

• 305 m in diameter

• The surface concentrates the faint radio waves towards an antenna.

• The larger the telescope the more it can collect.

Radio Telescopes

• Long Wavelengths------Short Wavelengths

• Radio/Infrared/Visible/UV/X-Ray/Gamma

Other Telescopes

Observatories• A building that contains

one or more telescopes.

• Most are on Mt Tops- Less atmosphere and less light pollution from cities.

• Mauna Kea- Best Site

• 4,200 m above sea level

Observatories

• Free of Clouds

• No light Pollution

• Less Atmosphere

Satellites• Earth’s atmosphere blocks

out most of the short wavelengths on the Electromagnetic spectrum.

• (U-V, X-Ray and Gamma Rays)

• Rely on satellites to detect these forms of radiation.

• Very Detailed Images

• Hubble- Reflecting Telescope– Collects- IR, Visible and UV

• Chandra- X-Ray Observatory– Detects X-rays.

Satellites

D. HubbleD. Hubble

B. Einstein B. Einstein

C. GalileoC. Galileo

A. WagnerA. Wagner

Which scientist was the first to use a refracting telescope?