Telescopes Galaxy 3 Galaxy 1 Galaxy 4 Galaxy

Telescopes

Galaxy 3 Galaxy 1 Galaxy 4 Galaxy 2 How many galaxies can you see

Exploring the Universe Telescopes – are Fantastic!

What they find ! The Universe contains the most amazing objects The Questions – How do they find them? What do they use?

Optical Telescopes • Most common type of telescope • Used to study visible light from objects • Allows you to see millions of stars and other objects

Refracting Telescopes • Uses lenses to gather and focus light • Has an objective lens that bends light that passes through it and focuses the light to be magnified by an eyepiece

Reflecting Telescopes • Uses a curved mirror to gather and focus light • Focuses on all the colors of light • Gathers more light than refracting telescopes

Very Large Reflecting Telescopes • Several mirrors work together to collect light and focus it in the same area

Optical Telescopes and the Atmosphere • Air pollution, water vapor, and light pollution distort the images produced by optical telescopes. • Collects visible light and focuses it to a focal point for closer observation.

Other Telescopes – Hubble Space Telescope • Does not travel to stars, planets, or galaxies • Whirls around Earth at about 17, 000 mph • About as long as a school bus • Has an unobstructed view of the universe • First major optical telescope to be placed in space

The Electromagnetic Spectrum • All of the frequencies or wavelengths of electromagnetic radiation

Detecting Electromagnetic Radiation • The Earth’s atmosphere blocks most invisible radiation from objects in space. • Each color of light is a different wavelength of electromagnetic radiation. • Radiation that can pass through the atmosphere includes some radio waves, microwaves, infrared light, visible light, and some ultraviolet light.

Nonoptical Telescopes • Detect radiation that cannot be seen by the human eye • Observes things at several wavelengths

Radio Telescopes • Detect radio waves, not light waves • Much larger than optical telescopes

Linking Radio Telescopes • Produces detailed images of the universe • When linked together, they work like one giant telescope

Nonoptical Telescopes in Space • Placed in space because most electromagnetic waves are blocked by Earth’s atmosphere

• Turn in your textbook to page 563. • In complete sentences, answer questions 1 and 2. • Write and answer in complete sentences questions 3, 4, 6, 9, 10, and 11.