Astronomy

Got nothing this time…

My mind has been in outer space (hahahahahaha)

Astronomy

• Astronomy• Is the study of the universe, the stars, planets

and all other objects in space. • We use astronomy as a guideline for our own

history.

Earth and the Moon

• Lunatic• Lunacy• There is an illogical belief that the moon could

cause someone to become unstable.

Phases of the Moon

• The moon completes one revolution around the Earth in just less than one month.

• Revolution: • To go around another object• Rotation:• To circle around your own axis (spin)• During this revolution for the moon, the

lighted areas of it appears to change shape.

• These are the PHASES (apparent change in shape) of the moon.

• These are caused by the changing relative positions of the Earth, the sun and the moon.

• When the moon and the sun are on the same side of Earth, the moon’s dark side faces Earth.

• New Moon

• When the moon is opposite the sun, we see the fully illuminated portion of it.

• Full Moon

• If the position of the moon and the sun are 90 apart, we see half of the moon lighted and ̊half in shadow.

• Quarter Moon

Phases

Eclipses of the Moon and Sun

• Two parts to a shadow:• Umbra: the inner, darker part• Preumbra: the outer lighter part

• When the sun shines on the Earth and the moon, a shadow is cast out into space from both.

Lunar Eclipse• Lunar Eclipse:• An eclipse when the moon moves into Earth’s

shadow.• The moon turns coppery red.• WHYYYYY?

Solar Eclipse

• Solar Eclipse:• An eclipse of the sun that occurs when the

new moon briefly moves between Earth and the sun.

• Rare

The Moon and Tides• Tides:• The twice daily rise and fall of the oceans.• Most places the difference between the tides

is only 3 feet. • The cause of the tides is the gravitational

attraction of the moon and the sun.• The sun and the moon pull on the water and it

is then pulled up towards the moon.

Spring Tide and Neap Tide

• Spring tide:• The highest high tide or the lowest low tide• These occur near the new and the full moon

phases • (not only in the spring!!!)• Neap tide:• When there is little to no difference between the

tides.• These occur near the quarter moon phases.

How The Moon Revolves • Ellipse: • The shape that a satellite orbits around an

object (not a perfect circle).• An ellipse is defined by two fixed points called

foci.• These points are intersected by a major axis.

Ellipses and Planets• All planets in our solar system revolve around the

sun due to the gravitational attraction of the sun.• All of these revolve in this flattened circle orbit

known as an ellipse. • Eccentricity describes how much an ellipse looks

like a circle or a flat line.• Eccentricity is a decimal. • Eccentricity close to 1: it looks like a flat line• Eccentricity close to 0: it looks like a circle

To Find Eccentricity

• The equation for eccentricity is:• e= d

Le= eccentricityd= distance between the fociL= the length of the major axis

Practice

• One of the foci is always going toBe the sun and the other is an imaginary point

2cm

4cm

e= ?d= 2L= 4

e= .500

The Solar System

• The solar system is about 4.6 billion years old.• The age of the universe is about 13 billion

years old (formed through the Big Bang).• Big Bang:• The rapid expansion of concentrated matter

that created the universe.

Planets of the Solar System

• The 8 planets can be divided up into two groups:

1.Terrestrial Planets2.Jovian Planets

Terrestrial Planets

• Terrestrial planets are rocky planets.• These include:• Mercury,• Mars, • Venus, • Earth • and Plu….nevermind

Jovian Planets• Jovian planets are also called gas giants (planets

made of gas).• These are planets that are made up of compressed

gases surrounding a tiny liquid and/or rocky ore.• These include:• Jupiter,• Saturn, • Uranus,• And Neptune

Cleavage/ Fracture

Hardness (compared to known substances)

Luster (metallic or non-metallic)

Distinguishing Characteristics

Rock Identification• Igneous Rocks:• Crystals• Extrusive• Vesicular• Intrusive

Sedimentary Rocks• Three Types:• Clastic/ Fragmental• Crystalline• Bioclastic• Horizontal Layers• Fossils

Metamorphic Rocks

• Regional • Contact• Foliation• Banding

Asteroids

• Asteroids:• rocky objects that are mostly located in a belt

between the orbits of Mars and Jupiter.• These range in size from roughly 1000km (600

mi) in diameter down to the size of a pebble.• Very few asteroids cross path with the orbit of

Earth’s.• 65 million years ago in the Yucatan (near

Mexico)

Meteors

• Meteors:• burning objects that produce streaks of light

visible at night.• Shooting stars

Comets

• Comets:• icy celestial objects which originate in a region

beyond the planets. • Halley’s Comet

The Sun• The sun is the nearest star to the Earth.• Star:• A large, self-luminous body in space that

creates its own radiant energy. • Stars get their energy through the process of

nuclear fusion.• Nuclei of two hydrogen atoms join together to

form a helium nucleus.

Sunspot

• These are temporary storms on the visible surface of the sun.

• They are cooler and dimmer than the normal surface of the sun and they usually occur in pairs.

Galaxies

Make Up of the Universe

• The universe is evolving to this day.• Universe• Galaxy• Solar System• Star• Planet• Moon• Mr. O’D

Evolution of the Universe

• Redshift:• Red lines that are evidence that distant

galaxies are rushing away from us at great speeds.

The Future