space science – lesson 1: components of space. what are you made of? space science – lesson 1:...
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Space Science – Lesson 1: Components of Space
What are you made of?
Space Science – Lesson 1: Components of Space
“The Most Astonishing Fact”Video
Space Science – Lesson 1: Components of Space
Space Science – Lesson 1: Components of Space
Our Solar SystemSolar system: a star and all the objects that travel in orbit around it
Our solar system is located in an outward spiral of Milky Way galaxy.
From NASA at http://solarsystem.nasa.gov/planets/index.cfm
Lesson 1 – Components of Space
Lesson 1 – Components of Space
Theories of the solar systemThere have been historically two models to explain the rotation of celestial objects around Earth:
1. Geocentric Model: Everything (sun & other planets) revolve around Earth
•Proposed by Pythagoras, an ancient Greek scientist
•We are the center of the universe
Lesson 1 – Components of Space
Theories of the Solar System
2. Heliocentric Model: The Earth and planets revolve around the Sun
- Heliocentric model (helio = Sun)
- Proposed by ancient Greek, Aristarchus
- Was rejected until the 1600’s
•But was supported by Polish astronomer Nicolas Copernicus and Galileo (1564–1642) supporter of Copernicus’s ideas
• In 1609, Galileo he used a telescope for the first time to view Moon and planets; observations exposed errors in the geocentric model
Despite the amount of evidence to support the
heliocentric model, there are still people who
reject his model.i
Theories of the Solar System
What are some
components of the Solar
System?
Space Science – Lesson 1: Components of Space
Other space
objects
Planets
Stars
Comets
Moons
Asteroids
Satellites
Dwarf Planets
Space Science – Lesson 1: Components of Space
Components of Our Solar SystemLesson 1 – Components of Space
Key Terms:
1. Planet – object orbiting a star or stellar remnant that is big enough to be rounded by its own gravity
2. Dwarf Planet – much smaller than a planet (smaller even than Earth's moon)
- Orbit the Sun just like the eight major planets
- Not able to clear their orbital
- E.g. Pluto
Key Terms: 3. Moon (natural satellite) – celestial body that orbits another body
(e.g. a planet)
4. Star – huge ball of gas held together by gravity- Central core is extremely hot and produces energy- Some energy released as visible light
5. Meteroroids – Little chunks of rock and debris in space are called meteoroids
- They become a meteor (shooting stars) when they fall through a planet's atmosphere
- When they land on the ground they are called meteorites
Lesson 1 – Components of Space
Key Terms: 5. Comet – snowballs of frozen gases, rock and dust
- ~ size of a small town - Dust & gases form tail that stretches away from Sun for millions of km- Has a very elliptical orbit
6. Asteroid – Rocky, airless objects that orbit the Sun- Too small to be dwarf planets & planets- Tens of thousands gathered in the main asteroid belt b/w the Mars &
Jupiter- Asteroids that pass close to Earth called near-earth objects.
7. Satellite – artificial object that has been intentionally placed into orbit (different from natural such as the moon)
Lesson 1 – Components of Space
“Our Solar System”Video
Space Science – Lesson 1: Components of Space
•Ancient astronomers saw points of light that appeared to move among the stars
- They called these ‘planets’, meaning ‘wanderers’
- Named them after Roman gods
Can you name the 8 planets?
Hint: One is named after him
Planets
The Solar System - Planets
•Term ‘solar system’ derived from “sol” meaning the Sun
•8 Planets (in order starting from closest to the Sun): 1. Mercury2. Venus3. Earth4. Mars5. Jupiter6. Saturn7. Uranus8. Neptune
*Pluto no longer considered a planet known as dwarf planet planet
Planets
Mnemonic device: My Very Elegant Mother Just Served Us Nine Pizzas
•4 innermost planets called terrestrial planets (meaning “Earth-like”) - Almost circular orbits around Sun- Mercury, Venus, Earth, & Mars
•The larger outer planets called gas giants - Outer layers are composed of gases such as hydrogen and helium- Move in elliptical or oval orbits- Jupiter, Saturn, Uranus, & Neptune
The Planets
The terrestrial planets
http://solarsystem.nasa.gov/multimedia/gallery/terr_sizes.jpg
The Planets
The gas giants
http://solarsystem.jpl.nasa.gov/multimedia/gallery/gas_sizes.jpg
The Planets
http://solarsystem.jpl.nasa.gov/multimedia/gallery/outer_orb.jpg
The Planets
The planets to scale. The rings of the gas giants are not shown.
The Planets
http://solarsystem.jpl.nasa.gov/multimedia/gallery/solarsys_scale.jpg(Distance between objects not to scale)
The Planets
Earth
How small are we?
source: Celestia (application)(Distance between objects not to scale)
The Planets
Earth’s Movement In Space•Babylonians, Mayans, indigenous
Australians used the movements of the Sun and Moon to define their days, months, seasons, and years
- Developed complex ways to predict seasonal changes
- Allowed ancient people to plan when to plant crops
- Survival depended on this knowledge of the Earth’s movement in space
Earth’s Movement In Space
•Planets rotate on their axes as they orbit Sun
•Rotation: time taken for a planet to spin once on its axis
- 1 rotation = 1 day
•Revolution: time taken to orbit the Sun once
- 1 revolution = 1 year (365.25 days)
•The earth spins on its axis, causing alternating day and night
Earth’s Movement In Space
Can you predict a planet that would have long “Earth-years”?
Which planets would have short days?
•The Earth spins once on its axis in a day, and takes a year to orbit the Sun.
Earth’s Movement In Space
•As the Earth orbits the Sun, tilt causes different parts of the Earth to experience different heating effects
•Summer solstice days are longest
•Winter solstice days are shortest
•At the two equinoxes, length of day = length of night
Science Focus 1: Coursebook
Earth’s Movement In Space