Astronomy and Space Mr. Norris

DAY 1 Objective Objective – I can explain how the universe formed and the laws governing it.

What is Astronomy? The science that studies the universe that deals with: – Properties of objects in space – Laws under which the universe operates

How the Universe Started? 1.Big Bang Theory – Everything was confined to a dense, hot, super- massive ball – About 13.7 billion years ago, a violent explosion occurred – Material went in all directions – Marks the beginning of the universe

2.Galaxy Forms – Galaxy: groups of starts, dust and gases held together by gravity – Our galaxy is THE MILIKY WAY 3.Formation of Solar System – Nebular Theory Formed from a rotating cloud of dust and gas First the Sun formed Next the planets formed

Types of Galaxies A.Spiral – Disk shaped with concentration of stars in the centers – Arms extended from center – Ex: Milky Way Galaxy

B.Elliptical – Round to oval in shape – 60% of galaxies C.Irregular – No definite shape – Mainly young stars

The Expanding Universe Theory Galaxies are moving away from each other The Universe is Expanding

LAWS OF ASTRONOMY

Kepler’s Laws of Planetary Motion 1 st Law – The orbit of the planets are ellipses with the sun at one focus

2 nd Law – The line joining the planet to the sun sweep out equal areas in equal times as the planet travels around the ellipse 3 rd Law – The length of time it takes a planet to orbit the sun and its distance to the sun are proportional

Law of Universal Gravitation Developed by Sir Isaac Newton Describes Gravity Based on the masses of objects and distances between them

DAY 2 Objective Objective – I can explain the motions of the Earth and how it affects the Earth

Motions of Earth

ROTATION Turning or spinning of a body on its axis Causes day and night Two ways Measured – Mean Solar Day – Sidereal Day Mean Solar Day – Time interval from one noon to the next (24 hours) Sidereal Day – Time it takes for Earth to make one complete rotation with respect to a distance star – 23 hours, 56 mins, 4 sec

Revolution Motion of a body along a path around some point in space Earth’s orbit is elliptical Takes 1 year Earth distance from the sun varies – Perihelion – Aphelion Perihelion – Closet to the sun – Occurs on January 3 rd Aphelion – Farthest from the sun – Occurs on July 4th

Precession Slight movement of the direction of which the Earth’s axis point Tilt degree does not change Happens over 26,000 years (complete cycle) Points to two stars – Polaris (currently pointing to) – Vega

Nutation Oscillatory movement of the axis of a rotating body or a wobble Occurs about 18.6 years

Barycenter The center of mass where two or more celestial bodies orbit each other The point balance each other

Earth’s Axis Tilted 23.5 degrees Causes season on Earth – Tilt is towards the sun indicates warmer season – Tilt away from the sun indicates cooler seasons

Earth’s Shape: The Moon’s Affect Tides – Changes in elevation of the ocean surface – Caused by Gravitational Pull of the Sun and Moon

Types of Tides Spring Tide – During a full and new moon – Gravitational pull of moon and sun added – Extreme high and low tides Neap Tide – During the 1 st and 3 rd quarter of the moon – Gravitational pull of moon and sun are offset – Tide Range is very small

DAY 3 Objective Objective – I can explain how the sun works and affect itself and Earth.

The Sun Layers (Structure inside out) 1.Core – Where energy is produced 2.Photosphere – Surface of the sun 3.Chromosphere – Thin layer of hot gas 4.Corona 1.Outer most layer that is very weak

Sun’s Motion It is not stationary Pulled by the planets gravity – Very slight back and forth motion Orbits the solar systems barycenter

Producing Energy Fusion – Atoms combine together – Used to produce energy – What the sun does Fission – Atoms split in two – Used to produce energy – What nuclear power plants do

What does the Sun Emits? Electromagnetic Radiation – Different waves of light based on wavelengths and frequency – Arranged on the Electromagnetic Spectrum

Electromagnetic Spectrum Radio Waves—lowest energy Infrared waves Visible Light (ROY G BIV) UV Rays X-rays Gamma Rays—highest energy

DAY 4 Objective Objective – I can explain how the Sun’s energy affects Earth – I can explain the Earth’s protects itself

Solar Radiation in Atmosphere 1.Absorbed by objects (like clouds) – 20 % 2.Reflected back to Space – 30% 3.Reaches the surface – 50%

When it Reaches the Surface Absorbed by Land or Water – Land will heat faster than water – Land will cool down faster than water Vegetation uses it

How Vegetation Uses Solar Energy They preform Photosynthesis Transformed into chemical energy Plants use sunlight to produce sugar Formula: 6H 2 O + 6CO 2  C 6 H 12 O 6 + 6CO 2

Earth’s Protection Earth Magnetic Field – Created by Earth’s core – Surrounds the Earth – Stops solar winds from the sun

When Magnetic Field & Solar Winds Met? The solar winds go around the Earth At weak spots near the poles, Auroras form

Without the Magnetic Field Solar winds would take away the ozone layer Ozone protects Earth from harmful UV rays Atmosphere would disappear Earth would not be livable