Ch 22: Exploring Space

“Imagination is more important than knowledge”

-Albert Einstein

Section 1: Rocket Science

ROCKET-- machine that uses escaping gases to move

THRUST -- the force that accelerates a rocket

Robert Goddard – 1st person to build rockets & known as the “father of modern rocketry”

Rockets work according to…

Newton’s 3rd law of motion:For every action there is an equal and

opposite reaction

Orbital velocity: speed and direction a rocket must have to orbit Earth (8 km/s)

Escape Velocity: speed and direction a rocket must have to completely break away (escape) from a planet’s gravitational pull

(11 km/s)

NASA: National Aeronautics and Space Administration

• NASA was formed in 1958 to compete with Soviet Union’s rocket program. – Occurred during the Cold War (United States vs. Soviets)

– At this time, the Soviets were already ahead…

Section 2: Artificial Satellites

Artificial Satellite: any human-made object placed in

orbit around a body in space

The Soviet Union launched the first artificial satellite, Sputnik 1, in December of 1957.

• This began the “Space Race” between the U.S. and Soviet Union, and influenced the creation of NASA

While the first attempt failed, the United States followed by launching Explorer 1, 4 months later in 1958.

Low Earth Orbit (LEOs): an orbit located a few hundred km above the Earth’ surface

• Satellites in LEO move quickly, placing them out of contact much of the time– Defense and spying

• Satellites in LEO eventually spiral toward Earth

Geosynchronous Orbit: an orbit much higher than LEO; satellite travels at a speed that matches the rotational

speed of the Earth exactly

• Satellites in GEO are positioned above the same spot on Earth at all times. – Communication – Local Weather

Satellite programs are used for:

• Weather observations• Communications• Mapping the Earth• Tracking ocean currents• Crop growth• Urban development• Environmental Observations

Space Shuttle: a reusable vehicle that takes off like a rocket and lands like an airplane

• Can take up to 8 astronauts into Low Earth Orbit (LEO) to: -launch satellites -work on International Space Station

• Missions last up to two and a half weeks

Section 4: Living and Working in Space

Famous First AstronautsYuri Gagarin — First human to orbit the Earth (Soviets April ’61)

Alan Shepard — First American to reach space, but NOT orbit (U.S. May ’61)

John Glenn — First American to Orbit the Earth (U.S. Feb ’62)

Space Station: long-term orbiting platform from which other vehicles can be launched or scientific research can be carried out.

• The International Space Station (ISS) is a collaboration the US and 15 other countries

(Russia, Canada, Japan, Brazil, Belgium, Denmark, France, Germany, Italy, The Netherlands, Norway, Spain, Sweden, Switzerland, and the United Kingdom)

SKY LAB• Sky Lab was U.S.’s first space station

– Launched in ’73– Fell into Indian Ocean in ’79

Remember…all objects in LEO will eventually fall to Earth, unless we prevent it

Project Mercury (1961-1963):• 1-manned spacecraft• Purpose:

– To orbit a manned spacecraft around Earth

– To investigate man’s ability to function in space

– To recover both man and spacecraft safely

Project Gemini (1965-1966): • 2-manned spacecraft• Purpose:

– To subject man and equipment to 2 week space flight

– To rendezvous and dock with orbiting vehicles

– To perfected methods of entering the atmosphere

Apollo Missions (1967-1972): • 3-manned spacecraft• Purpose:

– Scientific exploration of the Moon– Missions 7-17, landing 12 men on the

moon

• Missions 7-17, landing 12 men on the moon

• The Apollo spacecraft had 3 parts:– Command Module– Service Module– Lunar Module (LEM)

Apollo 11• First landing on the moon—July 20, 1969

– Neil Armstrong: 1st man to walk on moon– Ed “Buzz” Aldrin: 2nd man to walk on moon

Neil Armstrong Buzz Aldrin

Michael Collins

Apollo 13• Scheduled to be 3rd mission to land on moon• Due to an explosion on the Service Module, they had

to use the Lunar Module as a “life boat” and never made it to the moon

• They returned safely to Earth in the Command Module

The Return of the Apollo 13 Astronauts

Saturn V

Space Shuttle

Aries IAries V

NASA’s Future• Missions to the Moon…then on to Mars