JC Science - Earth and Space

Astronomy

The study of the universe beyond the earths atmosphere

Geocentric Model

Model of the Solar System with the Earth in the center. First created by the Greeks.

Heliocentric Model

A representation of the relationship between the Sun and planets in which the planets revolve around the Sun. Copernicus proposed the model.

A celestial object

A a naturally made object outside the earths atmosphere

Star

A celestial bid that generates its own heat and light, consists of a gas held together by its own gravity

Planet

A planet is a celestial body that is in orbit around a star

Moon

A moon is a natural satellite of a planet

Asteroid

An asteroid is a small rocky body orbiting the sun

A comet

A comet is made from ice and dust and orbits the sun

A comet's tail always points

away from the sun due to solar winds

Solar system

The solar system is a group of planets, asteroids, comets and other celestial objects

Galaxy

A galaxy is a very large system of stars held together by gravity

What is the centre of our solar system

Sun

The size of our solar system is controlled by how far out it's ———- can control objects

Gravity

Our 8 planets

Mercury

Venus

Earth

Mars

Jupiter

Saturn

Uranus

Neptune

Order of planets from the sun

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune (My Very Excited Mother Just Served Up Nachos)

Haley's comet is visible from earth approximately every —— years

75

Our solar system is part of what galaxy

The Milky Way galaxy

Outer space is what?

Empty volume that exists between galaxies

What is the most commonly accepted theory for the formation of the universe

The Big Bang theory

Describe the Big Bang theory

About 14 billion years ago all the mass and energy of the universe existed in a bubble the size of a pinhead which was hot as dense. It suddenly exploded and expanded to the size of earth now. Over time protons, neutrons and electrons were made and formed atoms. After 5 billion years these cloud of atoms created the first stars. After 5 billion years these stars died and exploded (supernova). This forced new heavier elements which gathered to create planetary systems and galaxies

What evidence is there for the Big Bang (1)

Edwin Hubble discovered that the universe is constantly expanding. We know this due to redshift in light as objects move away.

Redshift

shift of light to a longer wavelength as it moves away

What evidence is there for the Big Bang (2)

There is energy called Cosmic background radiation remaining everywhere in space left from the Big Bang

Gravity

-Known as the glue of the universe

-if two masses are placed near each other they will be attracted

-if the mass is small the force of attraction is small

-if the mass is large the of attraction is large

What happens as you move away from a celestial body

As you move away the force of gravity becomes less and less

What can planets be composed of?

Rock (earth) or gas (Jupiter)

rocky (terrestrial) planets

Mercury, Venus, Earth, Mars

Gaseous (Jovian) Planets

Jupiter, Saturn, Uranus, Neptune

Planets of greater density are likely to be made of ———-

Rock

Planets of less density are like to be made of ————

Gas

The earth orbits the sun every ——— days

365.25

The earth rotates on its own ———- every 24 hours this causes day and night

Axis

The moon orbits the Earth approx every —— days this causes moon phases

29

The ——- is the primary source of energy for the earth. It provides energy for photosynthesis and heats the earth

Sun

Earth's tilted axis

Tilted 23.5° relative to its orbit around the Sun

Causes Seasons- different areas receive different heat intensity throughout the year

In the summertime the northern hemisphere is titled ———— the sun

Towards

In the winter the northern hemisphere is titled ———- from the sun

Away

Does the moon create its own light?

No, it reflects light from the sun

Waxing

getting bigger

Waning

getting smaller

New Moon

A moon that is completely dark

Waxing Crescent

moon phase that comes after a new moon and before a first quarter moon; less than half of the moon is lit up on the right side

first quarter moon

The phase of the moon when it is one-quarter of the way through its orbit, and we see half of the moon lighted

Waxing Gibbous

A phase of the moon that comes after a 1st quarter moon and before a full moon where almost all of the moon is lit up from the right to the left, except a small bit on the left.

full moon

moon phase when the entire side facing Earth is illuminated.

Waning Gibbous

A phase of the moon that comes after a full moon and before a last quarter moon where all of the moon is lit up except for a small bit on the right side of the moon that we can see.

third quarter moon

The phase of the moon when it is three-quarters of the way through its orbit, and we see half of the moon lighted

Waning Crescent

moon phase that comes after a third quarter moon and before a new moon; less than half of the moon is lit up on the left side

When does an eclipse occur

When a celestial body gets in the way of sun illuminating another celestial body

Lunar eclipse

Earth comes between sun and moon

Solar eclipse

Moon comes between sun and earth

Benefits of space exploration

- Satellites for communication

-Efficient solar panels

- Battery technology

Hazards of space exploration

-dangerous traveling to and from

- Radiation can cause cancers

- Bone density decreased