UNIT 5

Unit 5:Space Exploration

Focusing Questions

• What technologies have been developed to observe objects in the sky, and what discoveries were made with them?

• How has the development of these technologies contributed to the exploration, use, and understanding of space?

• How have technologies designed for space science been applied to produce benefits on Earth?

Topic 1- For Your Eyes Only

Look into the sky... You see the Sun move through the sky during the day...You see the Moon, stars and planets move through the sky at night.

These objects rise in the east and set in the west. This motion is caused by Earth’s rotation

Objects DO NOT revolve around Earth.

• When we look at the sky, our common sense tells us that Earth doesn’t move. It seems as if everything in the sky travels around our planet.–We use Earth as a fixed frame of

reference to view the sky

• Frame of reference:– Set of axes of any kind that is used to

describe the positions or motions of things, • Ex: equator and prime meridian for

longitude and latitude

Example:• A car is moving north at 60km/h. The

driver sees a sign beside the road ahead of him. What is the velocity of the sign:– Relative to the car?• 60km/h

– Relative to the ground?• 0km/h

To Do:• Frame of Reference Worksheet

Quick Refresher of the Planets:

• Mercury• Venus• Earth • Mars• Jupiter• Saturn• Uranus• Neptune

Inner planets

Outer planets

What Our Ancestors Saw...

• Celestial Bodies:– All objects seen in the sky • the Sun, Moon, stars, and planets

• Constellations:– Grouping of stars that form

patterns, which appear like objects and are given names• Ex: Ursa Major

– On a successive day, stars rise 4 minutes earlier than the day before!• This means that there are different

stars in the night sky over a period of months!• Sun, Moon, Mercury, Venus, Mars,

Jupiter and Saturn rise and set at different rates than the stars

This lead to the creation of calendars!

Ancient Myths

• Astronomy:– The science of the stars and other heavenly bodies• Their motion, position, size, etc.

Sky Co-ordinates• Astrology:– Claiming to foretell the future by the supposed

influence of the stars, planets, etc. on human affairs.

– Some ancient peoples wanted to accurately measure the celestial bodies’ locations in the sky.

– Azimuth: measured clockwise from north (divided into 360 degrees). A compass is used to measure this.

– Altitude: measures a celestial body’s angle above the horizon in degrees (divided by 90 degrees). An astrolabe is used to measure this.

The Earth-Centered Model

• Aka Geocentric Model:– A model of the universe that places the Earth at

the centre with the Sun, moons and planets revolving around it.• Ideas bases on Greek philosopher Aristotle

– It was difficult to explain why Jupiter Mars, and Saturn sometimes reversed their direction (called retrograde motion)• To account for this, Ptolemy’s model gave these planets

another level of circular motion called epicycles.

Sun-Centered Model (Heliocentric)

• Model that places the Sun at the centre with the Earth, the planets, and moons revolving around it. – Proposed by Polish astronomer Nicholas Copernicus• Uses circular motion and the planets have epicycles • 1609: Johannes Kepler predicted the planets’ motions.• Ellipse: a figure that looks like a squashed circle; planets

move in elliptical orbits around the sun.

• Revolve:– How the Earth and all planets travel around the

Sun

• Rotate:– The turning of Earth on its axis.

To Do:

• Altitude/Azimuth worksheet

• Topic 1 Review:– Pg. 365 #1, 2, 5, 6

PLANET PROJECT

• Create a project that shows at least 5 similarities and 5 differences between Earth and another planet in our solar system.

• Present in a creative way (NO POWERPOINT!)

• Things to Remember: – Correct info– Organization– Neatness– 5 similarities and 5 differences– On time– creativity