Unit 4 Space

Chapter 10…What we know about the universe has taken us thousands of years to learn

4.01 Describe and explain the apparent motion of celestial bodies. Include:

• Moon • Sun • Planets • Comets • Asteroids

4.02 Define celestial bodies.

A natural object in space.

Includes:planetscometsmoonsstarsasteroids

Patterns made up of stars.

Pattern made up of stars

4.03 List examples of constellations and recognize them on a sky chart. Include:

Ursa MajorBig Bear (Big Dipper)

Ursa MinorLittle Bear (Little Dipper

Orion

Cassiopeia…The Queen

Leo the Lion

Seasonal Constellations• Occur because the

earth moves around the sun allowing us to see different part of the sky every season

• See page 360 for examples

Winter Constellation

4.04 Identify that celestial body movement involves:• Celestial bodies move in cyclic paths

called orbits.• These orbits result from gravitational

forces.

4.05 Identify that planets and moons revolve on a central axis.

• Planets, suns and moons revolve on a central axis.

• Stars generally move from east to west.• The point around which the stars rotate

is the North Star… Polaris.• Ursa Major and Minor, and Cassiopeia

never go below the horizon.

4.06 Describe theories on the formation of the solar system.

• Done in next chapter

4.07 Describe the contributions made by various individuals to our knowledge and

understanding of celestial bodies and their motions. Include:

• Aristotle • Ptolemy • Copernicus • Galileo • Kepler • Newton

Aristotle(383-322 B.C.E.)

• Visualized the universe as being geocentric. This means the Earth is the centre of the universe and everything else revolves around it.

Aristotle(383-322 B.C.E.)

• He believed that the Earth was a sphere due to the curved edges observed during a lunar eclipse.

Ptolemy(83-168 C.E.)• Based his model on his

observations of Mars.• Mars orbital path creates

a loop or s-shape in the sky.

• His model showed each planet attached to a crystal sphere with its centre at Earth.

Ptolemy(83-168 C.E.)

• Each planet was not attached directly to its sphere but to an off-centre wheel (epicycle).

• Accepted for nearly 1500 years.

Copernicus(1473-1543)• Believed in a heliocentric

universe (Sun at the centre).

• The Earth rotated on its axis once daily and revolved around the Sun once a year.

Galileo(1564-1642)

• First person to view the “heavens” through a telescope.

• Allowed him to see objects Craters on the MoonSpots on the SunFour “stars” orbiting Jupiter

(called the Galilean Moons)

Johannes Kepler(1571-1630)3 Laws of Planetary Motion1. All planets move in ellipses

with the Sun at one focus.2.Planets sweep out at equal

areas of their elliptical orbit in equal times.

3. The time a planet takes to revolve around the Sun is directly related to how far away it is from the Sun.

Sir Isaac Newton (1643-1727)• Developed the three laws of

motion.• First to show that the force of

gravity affects all celestial bodies, causing them to stay in orbit.

Sir Isaac Newton (1643-1727)

• Invented the reflecting telescope which uses a curved mirror to focus the light to a point at an eyepiece.

4.08 Identify early technologies that advanced scientific observations about the solar system. Include: Stone CirclesDesigned and used

by ancient people to help predict the movement of celestial bodies

Help predict seasons and other natural phenomena

• Used to locate and predict the position of the Sun, Moon and stars.

• Along with a compass, it could be used to describe the position of any celestial body in relation to the direction North and to the horizon.

• Allowed for more accurate observations.

• Mariner’s used astrolabe to help navigate on the ocean.

• An optical device that uses lenses to gather and focus light to provide a magnified image.

• Invented by Galileo

The Telescope

Inner Planets• Mercury• Venus• Earth• Mars

Outer Planets• Jupiter• Saturn• Uranus• Neptune