ES - Astronomy

Big Bang Theory

The universe began from an infinitely small point of temperature (13.8 billion years ago)

Wavelength

Wavelength: Distance between successive peaks of a wave

Short wavelength found on left

Long Wavelength found on right 

As wavelength increases, frequency…

decreases

Nuclear Fusion

The process of combining smaller nuclei into larger nuclei and release energy 

Cosmic Background Radiation:

the faint leftover heat energy from the Big Bang that is found throughout the universe.

Red Shift

Occurs when Earth and a distant star in another galaxy are moving apart or running away from each other 

Blue Shift

Occurs when Earth and a distant star in another galaxy are moving or barreling towards (each other)

Milky Way

our galaxy, 13.2 billion years old; Spiral shaped galaxy 

How old is our solar system?

4.6 billion years old

Classification of our Universe from Biggest to Smallest

Universe- Galaxy-Solar System-Planet

Inner Planets

Mercury, Venus, Earth, Mars

Outer planets

Jupiter, Saturn, Uranus, Neptune

Asteriod Belt

 In between Mars and Jupiter 

Kuiper Belt

Located at the very edge of our Solar System (Pluto and Eris)

Terrestrial Planets (Inner Planets) descriptions

1. Closer to the Sun

2. Smaller

3. Rocky

4. Denser 

1. Jovian Planets (Outer Planets)

1. Farther from the Sun

2. Bigger

3. Gassy

4. Less dense

Heliocentric Model

 Sun as center of our solar system with planets moving in perfect orbits 

Modern Heliocentric Model

Sun is in the center and earth revolves around the Sun in elliptical orbits 

Geocentric

the model of the universe that states that Earth is at the center and all other objects in space revolve around it.

Revolution

planet’s movement around a star

4 Ways to measure gravity?

• The Greater the mass the more of a gravitational pull you will have
  

• The less the mass the less of a gravitational pull you will have

• As distance decreases gravitational force increases

• As distance increases gravitational force decreases

Keplers Three Laws

1. First Law (Law of Ellipses): Planets orbit the Sun in an oval-shaped path called an ellipse, with the Sun at one focus.

2. Second Law (Law of Equal Areas): A planet moves faster when it is closer to the Sun and slower when it is farther away.

3. Third Law (Law of Harmonies): The farther a planet is from the Sun, the longer it takes to complete one orbit.

Perihelion vs Aphelion

Closest position to the Star; faster orbital speed vs Farthest position from the Star; slower orbital speed 

On Earth, when does Aphelion occur and when does Perhelion occur?

Aphelion - Early July

Perihelion - Early January

Eccentricity

How elliptical/or circular the shape of an orbit is (closer to 0 less, closer to 1 more)

Apogee

Farther from the Earth

Perigee

Closer to the Earth

High Tide

ocean at highest point on shore

Low Tide

ocean at lowest point on shore

What is the cause of tides?

gravitonal attraction of the Moon and Sun

Why does the Moon have a greater cause of tides than the Sun?

The Moon is much closer to the Earth then the Sun

Spring Tides

Occur during a Full and New Moon phase

Moon: Highest High Tides, Lowest Low Tides, Moon, Earth, and Sun are all in a straight path

Neap Tides

Occur duirng 1st and 3rd Quarter, Lowest high tides, and Highest low tides, Earth, Moon and Sun are in a perpendicular path 90 degrees

Eclipse

 A celestial object being blocked by another celestial object

Solar Eclipse

The Moon Blocks the Sun’s light to the Earth

• Occurs during a New Moon phase

• Complete darkness if in Umbra

• Sun → Moon → Earth 

Umbra

darkest part of a shadow

Penumbra

outer rim of shadow (partial darkness)

Lunar Eclipse

The Earth’s shadow blocks out the Moon

• Full Moon

• Once Earth’s shadow no longer blocks the Moon: Moon looks blood red

• Sun → Earth → Moon

Moon and Earth’s Orbits

The Moon's orbit is elliptical and is tilted at a 5 degree angle relative to the Earth. This explains why Lunar Eclipses and Solar Eclipses aren’t monthly