Space Notes 1 Covers Objectives 1 & 2

Space Introduction Video

Celestial Bodies Refers to a natural object out in space 1) Stars 2) Comets 3) Moons 4) Planets 5) Asteroids

Constellations Constellations Song - YouTube patterns made up of stars 1) Ursa Major (The Great Bear) 2) Ursa Minor (The Little Bear) 3) Orion

Asterisms smaller groups of stars that are present within constellations 1) The Big Dipper (in Ursa Major) 2) The Little Dipper (in Ursa Minor) 3) Orion's Belt (in Orion)

Constellation containing an Asterism

Constellation containing an Asterism

Celestial Body Movement Celestial bodies move in a cyclic path called an orbit. Orbits result from gravitational forces Planets, sun, and moons all revolve on a central axis.

Stars (Ex: Sun) celestial bodies that give off light and heat but are very far away. Stars generally move from East to West the point around which the stars rotate is the north star “Polaris”

Night Sky in the Northern Hemisphere

Planets celestial bodies that orbit (revolve) the sun. They are held in these elliptical orbits by the gravity of the sun and rotate on a central axis creating day and night. Solar System Video - YouTube

Early Models of the Universe Aristotle(383-322 B.C.E.) Visualized the universe as being geocentric. This means the Earth is the center of the universe and everything else revolves around it. He believed that the Earth was a sphere due to the curved edges observed during a lunar eclipse.

Ptolemy 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.

Each planet was not attached directly to its sphere but to an off-centre wheel (epicycle). Accepted for nearly 15oo years. Geocentric to Heliocentric Video - YouTube

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 about 20x closer.

He observed: Craters on the Moon Spots on the Sun Four “stars” orbiting Jupiter (called the Galilean Moons)

Now that the Sun was placed at the centre of our solar system, other astronomers could work to understand the motion of the planets. Improvements in the telescope would show new and strange objects never imagined!

Johannes Kepler(1571-1630) Developed 3 Laws of Planetary Motion 1. 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.

Bookwork – Page 375 #1-6 and 8-10

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.

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

Technologies that advanced Scientific Observations Astrolabes are used to show how the sky looks at a specific place at a given time. Used to locate and predict the position of the sun, moon, and stars. (by drawing the sky on the face and marking it so positions in the sky are easy to find) To use an astrolabe, you adjust the moveable components to a specific date and time. Once set, much of the sky, both invisible and visible, is represented on the face of the instrument Typical uses of the astrolabe include finding the time during the day or night, finding the time of a celestial event (sunrise or sunset) and a reference to celestial positions

Along with a compass, it could be used to describe the position of any celestial body in relation to the direction North and the horizon. Allowed for more accurate observations to be made. https://www.youtube.com/watch?v=7COCkxpEvzs

Stone Circles Found all over the world but mostly in Europe (Stonehenge). Although no one knows why the structures were built (other than for burial), it was probably connected to agricultural events. https://www.youtube.com/watch?v=-OfJ5p-cXHs STSE – celestial navigation

Telescope Allowed people to view objects that could not be seen with the naked eye. https://www.youtube.com/watch?v=JChDGRhpAwA

Textbook Questions Pg 386 #2, 4, 8, 9, 13