December 21, 2011

ObjectiveIdentify the

scientists that contributed to modern astronomy

The SunQuiz at the end of

watchingHistory and tools of

Astronomy NotesIMAX: Space StationReview for test

TEST TOMORROW

Agenda

Ancient Greeks

Early Astronomy

Geocentric Model = Ptolemy Greek Astronomer• In the ancient Greeks’ geocentric model, the

moon, sun, and the known planets—Mercury, Venus, Mars, and Jupiter—orbit Earth.

Heliocentric Model = Nicolaus Copernicus

• In the heliocentric model, Earth and the other planets orbit the sun.

Planets usually move from W to E relative to the stars, but sometimes strangely turn around in a loop, the so called retrograde motion.

Retrograde motion of the Planets

The Birth of Modern Astronomy

Early Astronomy

Nicolaus Copernicus• Copernicus concluded that Earth is a planet. He

proposed a model of the solar system with the sun at the center. Heliocentric Model

This model explained the retrograde motion of planets better than the geocentric model.

The Birth of Modern Astronomy

Early Astronomy

German astronomer Johannes Kepler (1571-1630) helped establish the era of modern astronomy by deriving three laws of planetary motion.

Early Astronomy Galileo Galilei

Italian scientist Galileo Galilei (1564—1642) used a new invention, the telescope, to observe the Sun, Moon, and planets in more detail than ever before.

Early Astronomy Sir Isaac Newton

English scientist Sir Isaac Newton (1642—1727) explained gravity as the force that holds planets in orbit around the Sun.

• Refracting telescope • Uses a lens (called the objective) to bend

(refract) the light to produce an image

Astronomical tools

Reflecting telescope

• Uses a concave mirror to gather the light

Astronomical tools

The 200" (5m) Hale Reflector of Palomar Observatory is shown above. Until recently it was the world's largest optical/infrared telescope.

A steerable radio telescope at Green Bank, West Virginia

Radio Telescope

The 300-meter radio telescope at Arecibo, Puerto Rico

Radio Telescope

The value of the space program Personal Computers Colorization of black and white

movies Solar powered calculators Aluminized bags for snack food Weather satellites Halogen lights for cars Sports domes Microwave Ovens Pocket calculators Phone calls by satellite Laser guided missiles "Mylar" balloons "Blue Blocker" sunglasses

Digital watches and thermometers "DirecTV", "Dish Network", etc "Kevlar" for bullet proof vests "Mini Mag" flashlights Fishing line Fiber optics for phone calls "Vortec" engines in GM cars "Ovation" guitars and helicopter

blades

Medical scanners Electronic ignition in

automobiles Laser scanners in stores "Bulb Miser" devices for long

life light bulbs Weather Maps on television Juice boxes for "Hawaiian

Punch", etc "The Patch" medical device Breathing systems for Mt.

Everest climbers, Scuba divers and firefighters

“Flexon" eyeglasses and dental braces

Cellular phones and beepers Cable Television, H B O,

Showtime, etc Pens that write upside down

and under water Anti corrosive paint for bridges,

boats & Statue of Liberty

Scratch resistant coatings on sunglasses

Football helmets for the NFL Pacemaker batteries that last 20

years and can be recharged through the skin.

Compact Disks GPS Navigation Systems