Early Space ExplorersEarly Space Explorers

Aristotle

384-322

Ptolemy

85-165

Copernicus

1473-1543

Brahe

1546-1601 1564-1642

GalileoKepler

1571-1630

Newton

1642-1727

Aristotle

384-322

Early Space ExplorersEarly Space Explorers

Early Space ExplorersEarly Space Explorers AristotleAristotle

Laws of MotionLaws of Motion The natural state of objects The natural state of objects

is at restis at rest Heavy objects fall faster Heavy objects fall faster

than light objectsthan light objects

Early Space ExplorersEarly Space Explorers AristotleAristotle

Earth = center of universeEarth = center of universe Moon, Sun & 5 known Moon, Sun & 5 known

planets carried on planets carried on crystalline spheres crystalline spheres

Orbit are circularOrbit are circular Superluner vs. SublunarSuperluner vs. Sublunar

Ptolemy

85-165

Early Space ExplorersEarly Space Explorers

Early Space ExplorersEarly Space Explorers PtolemyPtolemy

Earth = center of universeEarth = center of universe Moon, Sun & 5 known Moon, Sun & 5 known

planets carried on planets carried on crystalline spheres crystalline spheres

Orbit are circularOrbit are circular

The Ptolemaic Solution

Dark Ages

The models developed by Aristotle and Ptolemy dominated astronomy for 14 centuries

Copernicus

1473-1543

Early Space ExplorersEarly Space Explorers

Early Space ExplorersEarly Space Explorers CopernicusCopernicus

Sun is near the center of Sun is near the center of universeuniverse

Planets rotate aroundPlanets rotate around SunSun on crystalline sphereson crystalline spheres

Orbit are circularOrbit are circular Simpler explanation for Simpler explanation for

path of planetspath of planetsInterior Planet

Exterior Planet

Early Space ExplorersEarly Space Explorers

Brahe

1546-1601

Early Space ExplorersEarly Space Explorers BraheBrahe

Earth = center of universeEarth = center of universe Sun and Moon rotate Sun and Moon rotate

around Eartharound Earth All other planets rotate All other planets rotate

around the Sunaround the Sun Very precise measurements Very precise measurements

of the heavens using a of the heavens using a sextantsextant

Early Space ExplorersEarly Space Explorers BraheBrahe

h = 2 D tan (½ )

D

h22

Early Space ExplorersEarly Space Explorers

Kepler

1571-1630

Early Space ExplorersEarly Space Explorers KeplerKepler

Sun = center of universeSun = center of universe Planets rotate around the Sun Planets rotate around the Sun

in in ellipticalelliptical orbits orbits 3 Laws3 Laws Kepler’s First Law

The orbits of the planets are ellipses with the Sun at one of

the foci

Early Space ExplorersEarly Space Explorers KeplerKepler

Sun = center of universeSun = center of universe Planets rotate around the Sun Planets rotate around the Sun

in in ellipticalelliptical orbits orbits 3 Laws3 Laws Kepler’s Second Law

The line between an orbiting planet and the Sun sweeps

out equal areas in equal times

Early Space ExplorersEarly Space Explorers KeplerKepler

Sun = center of universeSun = center of universe Planets rotate around the Sun Planets rotate around the Sun

in in ellipticalelliptical orbits orbits 3 Laws3 Laws

Kepler’s Third LawThe square of an orbit’s

period is proportional to the cube of the average distance between the planet and the

Sun P2 ~ a3

Early Space ExplorersEarly Space Explorers KeplerKepler

Early Space ExplorersEarly Space Explorers

1564-1642

Galileo

Early Space ExplorersEarly Space Explorers GalileoGalileo

Invented the telescopeInvented the telescope Moon: mountains, valleysMoon: mountains, valleys Sun: blemishesSun: blemishes

Early Space ExplorersEarly Space Explorers GalileoGalileo

Invented the telescopeInvented the telescope Disproved AristotleDisproved Aristotle

• Moon: mountains, valleysMoon: mountains, valleys• Sun: blemishesSun: blemishes

Light and heavy objects fall at Light and heavy objects fall at the same ratethe same rate

Early Space ExplorersEarly Space Explorers

Newton

1642-1727

Early Space ExplorersEarly Space Explorers

NewtonNewton

Miracle Year – 1665:Miracle Year – 1665:• Invented calculusInvented calculus• Law of GravitationLaw of Gravitation• First reflective telescope First reflective telescope

1667: 1667: Mathematical Principles of Mathematical Principles of Natural PhilosophyNatural Philosophy

Newton’s Laws of MotionNewton’s Laws of Motion

1. “Every object persists in its state of rest or uniform motion in a straight line unless it is compelled to change that state by forces impressed upon it”

2. “Force is equal to the change in mometum per change in time”

3. “For every action, there is an equal and opposite reaction”

Konstantin TsiolkovskyKonstantin Tsiolkovsky“Father of Russian Cosmonautics”“Father of Russian Cosmonautics”

1857-19351857-1935His Classic article His Classic article "Research into "Research into

Interplanetary Space by Means Interplanetary Space by Means of Rocket Powerof Rocket Power" was published in " was published in 1903, the year of the first airplane 1903, the year of the first airplane flight by the Wright Brothers. It flight by the Wright Brothers. It accurately described the state of accurately described the state of weightlessness and the theoretical weightlessness and the theoretical function of rockets in a vacuum. He function of rockets in a vacuum. He demonstrated why rockets would be demonstrated why rockets would be needed for space exploration, and needed for space exploration, and also advocated the use of liquid also advocated the use of liquid propellants that are used today. propellants that are used today.

Robert GoddardRobert Goddard“Father of Modern Rocketry”“Father of Modern Rocketry”

1882-19451882-1945His experiments with both solid His experiments with both solid and liquid fueled rockets formed and liquid fueled rockets formed much of the basis of the much of the basis of the development of ballistic missiles, development of ballistic missiles, earth-orbiting satellites, and earth-orbiting satellites, and interplanetary exploration. interplanetary exploration.

Wernher Von BraunWernher Von Braun1912 - 19771912 - 1977

Braun began working on a new secret weapon, Braun began working on a new secret weapon, the V2 Rocket. This 45 feet long, liquid-fuelled the V2 Rocket. This 45 feet long, liquid-fuelled rocket carried a one ton warhead, and was rocket carried a one ton warhead, and was capable of supersonic speed and could fly at an capable of supersonic speed and could fly at an altitude of over 50 miles.altitude of over 50 miles.

5,000 V-2s were launched, only 1,100 hit their 5,000 V-2s were launched, only 1,100 hit their target.target.

In 1952, Braun became technical director of the In 1952, Braun became technical director of the US Army's Ballistic Missile Agency at Huntsville, US Army's Ballistic Missile Agency at Huntsville, Alabama and was chiefly responsible for the Alabama and was chiefly responsible for the manufacture and successful launching of manufacture and successful launching of Redstone, Jupiter-C, Juno and Pershing missiles. Redstone, Jupiter-C, Juno and Pershing missiles.