earth in the universe discussion question review question
TRANSCRIPT
Earth in the Universe
Discussion Question
Review Question
The Universe
Age of the Universe
Believed that the Universe is extremely vast and more than 10 billion years old
Could be up to 13.7 billion years
Origin of the
Universe
Started with the Big Bang Most of the earliest atoms were hydrogen and helium Universe kept expanding in all directions and continues
to expand today
What is the Universe?
everything that exists in any placeAll the space, matter, and energy in existence
The Big Bang Theory
“All matter and energy started out concentrated in a small area and after a gigantic explosion, matter began to organize into subatomic particles and atoms”
Radiation from the Big Bang mixes with energy given off by stars throughout the universe. Cosmic Background Radiation: Long wave background
radiation (microwaves) that appears to come from all directions in the Universe
Discuss the Origin of the Universe
Video
The Electromagnetic Spectrum
What is the Electromagnetic Spectrum?
Is there any event in nature that allows you to view the entire
spectrum?
The Electromagnetic Energy
Various types of waves that transfer energy throughout space
Measured using the Electromagnetic Spectrum Scientists infer which elements are in an object based on the
electromagnetic energy emitted Based on composition of signature wavelength produced
Doppler Effect: Shifting of wavelengths Relative movement between Earth and the other celestial objects
cause the Doppler Effect
Video
How are you able to tell if an emergency vehicle is approaching?
The Doppler Effect
Red Shift Blue Shift
•“Longer” end of the spectrum• Indicates that objects are moving apart•Most, if not all, stars in the galaxy are shifted to the red end of the spectrum (evidence that universe is expanding) - Rate that universe is expanding is increasing
• “Shorter” end of the spectrum• Indicates that objects are moving closer together
Animation 1
What color wavelength would a nearby galaxy emit?
What is the approximate value of that wavelength?
The Structures of the Universe
A. What is at the center of this photo?B. Explain how this photo was taken.
Time Lapse Photo of stars. Galaxy
Galaxies
Collections of billions of stars and gases held together by gravity Average galaxy has over 100 billion stars There are over 100 billion galaxies
Elliptical Galaxy Irregular GalaxySpiral Galaxy
Three common types of Galaxies
What is the name of our galaxy and which type of galaxy is it?
Video
The Milky Way Galaxy
Galaxy where our Solar System is located
A Spiral Galaxy
Has @ least 200 billion stars
Stars A large ball of gas and dust held together by gravity
Produces a TREMENDOUS of energy results in shining Process called Nuclear Fusion
Size of stars vary Some are larger than our Sun Some size of planets or
moons & no longer emit energy
iPad “Planets” Activity
What is your Sun Sign?
Nuclear Fusion
When nuclei of smaller elements (H and He) combine to form the nuclei of larger elements Results in some of its mass converting to energy
Occurs ONLY under extreme heat and pressure Conditions only found in a star’s core (center)
Energy is radiated into space as electromagnetic energy
Explain the role of nuclear fusion prior to the formation of our universe.
How is a star’s brightness determined?
Luminosity Apparent Brightness
- Measurement of how bright a star is compared to the Sun, if all stars were the same distance from an observer. -
-How bright a star appears to an observer-Dependent upon the star’s absolute luminosity and its distance away from us
ESRT pg 15
Determine the luminosity of the following stars: Betelgeuse, Spica, Barnard’s Star
Star Type Size TemperatureNotes
Additional Notes
Main Sequence Average
- As surface temperature
increases, luminosity increases
- 90% of all studied stars- Most stars spend a majority of their life in
this stage- Smallest and coolest stars are called red
dwarfs
Giant10 to 100x
the diameter
of the Sun
Low-temperature stars
- Red, orange, and yellow giant stars are rare but commonly seen in the night sky because of
their large size and high luminosity - Late stage in evolution of main sequence
stars
Super Giant
100 to 1000x the diameter of the sun
Blue super giants: brightest and exhibit the
higher temperatures
- Late evolution of stars originally more massive than the sun
- Explodes in tremendous events known as supernovas
White Dwarf
Small - Hot on Surface- Not all are white
- Low Luminosity- Late stage evolution of Main Sequence Stars
Black Dwarf
Small - Cool- No more Energy
- Former white Dwarf- Very common (as there are trillions of
former white dwarfs)
Main Sequence Red Giant White Dwarf
Supernova explosion Black Dwarf
Video
Evolution of a Star Stage of a star depends upon its original mass
Process of a star “dying” out may take billions of years Some stars that were created during Big Bang still exist
The Solar System
Refers to any star or group of 2-3 stars that has other celestial objects orbiting (Satellites) Satellite: any [celestial] object that orbits or revolves around
another object
Our Solar System The Sun and all celestial object that orbit under its gravitational
force Sun is a medium-size Main Sequence star that is ~ 5 Billion years
old Result of gas and dust condensing into one or more mass
concentrations Due to gravity
What celestial object is a satellite of the Earth?
Our Solar System
List and describe the 5 parts of our solar system.
Part of Solar System Size Notes Description
Planets - Largest objects that orbit the Sun
- There are 8 planets - Spherical Shape
Moons- Small than the planet it orbits
- Celestial object that orbits a planet or asteroid as it orbits a Star- Approximately 175 moons in our Solar System
Asteroids- Smaller than Planets- Irregular Shape
- rock and/or metallic object-Independently orbits the Sun- No Atmosphere- Asteroid Belt: Large % orbit between Mars and Jupiter
CometsVaries - “Dirty Snowball”
- Largely ices mixed with rocks and metals- Solid is easily changed into gases when heated - This forms a visible tail
Meteoroids
Very small rock fragments(size of dime or sand grain)
Three categories 1. Meteoroid -orbits the Sun 2. Meteorite –Burns un in Earth’s Atmosphere creating a visible streak 3. Meteor – Reaches and lands on Earth’s surface, forms a impact crater
VIdeo
Video
Asteroid
Our Moon
MeteorComet
What is a shooting star?
Groups of PlanetsTerrestrial Jovian
Planets Mercury, Venus, Earth, Mars Jupiter, Saturn, Uranus, Neptune
Distance From Sun
Closest to the Sun Furthest from the Sun
Size Small Massive
Composition Rocky, SolidMany impact craters
Gaseous
Density High Low
Moons Few many
Rings None ✓✓
ESRT pg 15
Terrestrial Planets
Jovian Planets
What motion is illustrated in this image?
Describe the motion of each planet as clockwise or counterclockwise.
Rotation of a Planet
Rotation: movement (spinning) of a planet around an imaginary Axis Axis runs through the center of planet from Pole to Pole
Period of Rotation: amount of time it takes to complete one spin around the axis
6/8 planets rotate counterclockwise (same direction as revolution) Venus rotates clockwise Uranus rotates around axis @ equator
Balanced Forces
Inertia – concept that an object at rest will tend to remain at rest and an object in motion will remain in motion
Gravitation – the attractive force that exists between any two objects in the universe Closer together two objects, the greater the gravitational pull
Orbit of a planet around the sun is an example of the balance between inertia and gravitation
What is the Shape of Earth’s Orbit?An Ellipse
Shape of Planet’s Orbit
Orbit – planet’s path around the Sun Controlled by Sun’s gravitational pull Revolution: one complete orbit around the Sun
All planets revolve counterclockwise
All orbital paths are Elliptical or oval shaped Two center pts of ellipse called Foci Major axis – line that passes through both Foci across the widest
part of the ellipse
An ellipse is like a flattened circle
Foci
Major Axis
Eccentricity of an Orbit
Eccentricity – The degree of flattening or “oval-ness” of an ellipse Slightly eccentric when value is closer to zero (circle = 0) More eccentric when value is closer to 1 (flat line = 1)
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Eccentricity =
Distance between foci Length of major axis
Where would you be able to find theeccentricity of a planet in our solar system?
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Elliptical Orbits
Causes planets to vary in distance throughout its orbit Closest – Perihelion position Farthest – Aphelion position
Complete the following statement: The area of the triangle on the left is _________ to that on the right. (equal to; less than; greater than)Equal to
Perihelion Aphelion
Earth’s Position Closest to the Sun Furthest from the Sun
Our Season Early Winter Early Summer
Date January 3rd July 4th
Apparent Diameter of the Sun Greatest Least
Orbital speed of Planet Greatest Least
Kinetic Energy of Planet Greatest Least
Gravitational Attraction between Planet and the Sun
Greatest Least
Practice
Using the tools provided, demonstrate and calculate the eccentricity of the following ellipses:
Number Distance between Foci (cm)
Length of Major Axis(cm)
1 1 cm
2 2 cm
3 4 cm
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