Download Approximately 14 billion years ago, all matter and energy was

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Approximately 14 billion years ago,
all matter and energy was concentrated together in one area. Then, there was a huge explosion….
3‐1 THE BIG BANG
3 ‐ 2 G A L A X I E S & S TA R S
3‐3 TOURING OUR SOLAR SYSTEM
3‐4 ELLIPSES & ECCENTRICITY
FOLLOWING THE EXPLOSION…
 Subatomic particles formed (protons, electrons, neutrons)
 Atomic particles formed (simplest H and He)
 Heavier elements formed (Si, Fe…)
Billions of years later…  Atoms became planets and stars
Today…
 The universe is still expanding
COSMIC BACKGROUND RADIATION
HOW DO WE KNOW THE UNIVERSE IS STILL EXPANDING???
• A constant “cosmic background radiation” has been observed coming from all directions of our universe.
• This energy is the echo of the Big Bang
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ELECTROMAGNETIC ENERGY HOW IS ELECTROMAGNETIC ENERGY USEFUL?
(MORE IN CHAPTER 5)
•
Electromagnetic Energy ‐ Energy that is radiated, or given off, in the form of waves Wavelength – distance from one crest of a wave to the next crest (or from one trough to the next trough)
Just looking at Visible Light ‐ ROYGBIV
•
Each element (H, He, O, Br, Ne) emits energy at a specific wavelength The human eye can see visible light
‐Visible light is used in identifying elements in celestial objects (stars, planets, moons….)
•
Detect other forms of energy from other celestial objects using instruments
•
Can determine if objects are moving away, moving at same speed or moving toward Earth using the Doppler Effect
ELECTROMAGNETIC SPECTRUM
ESRT page 14
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EVIDENCE FOR THE BIG BANG
1. Background radiation from all of objects in the universe which is hypothesized to have originated during the Big Bang
2. Doppler Effect – shifting of wavelengths caused by the relative movement between objects
EVIDENCE FOR THE BIG BANG: DOPPLER EFFECT
• Shifting of wavelengths can occur with both sound and light
• Doppler effect is easier to observe with sound
 With sound you will hear a change in pitch
 Imagine an ambulance approaching a person standing on a sidewalk:
 As the ambulance moves closer the pitch becomes higher
 As the ambulance moves away the pitch becomes lower
Ambulance Doppler
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DOPPLER EFFECT WITH LIGHT
Blue
Remember each element has its own spectra that we can identify
We can notice changes or shifts in wavelengths of the spectra
blue shift – spectra shifted to the blue end of the spectra, the object is moving closer
red shift – spectra shifted to the red end of the spectra, the object is moving away
Red
Blue shift – object is moving closer
Blue
Red
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Blue
Red
Blue
Red
Blue
Red Shift – object is moving away
Blue
Red
No shift – object is moving same speed
Red
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THE UNIVERSE IS STILL EXPANDING
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REMEMBER…
• Most objects in the universe show a red shift
so the universe is still expanding since the Big Bang
• The objects furthest away show the greatest red shift, so moving away fastest
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• Red Shift = Moving AWAY (expanding)
• Objects in our universe show red shift for expansion
• Blue Shift = Moving Towards Observer
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Describe what you are looking at….
Within the universe, there are over 100 billion galaxies.
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TYPES OF GALAXIES
GALAXIES
• Galaxy ‐ a collection of billions of stars and various amounts of gas and dust held together by gravity
• Each galaxy averages about 100 billion stars
• There are over 100 billion galaxies in the universe
Elliptical Galaxy
Spiral Galaxy
Irregular Galaxy
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OUR GALAXY – MILKY WAY
Our galaxy’s name is the Milky Way
It has 200 billion stars and is spiral shaped
Our solar system is located on one of the spiral arms of the galaxy (Orion arm)
Our galaxy is 9.25 x 1017km
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WHAT IS A STAR?
Star ‐ large ball of gas held together by gravity
• They glow (self‐luminous) because they produce large amounts of energy by the process of nuclear fusion
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NUCLEAR FUSION
Nuclear fusion – combining of smaller elements (H) to form larger elements (usually He), along with tremendous amounts of energy • Occurs at extremely high temperature and high pressure conditions in the star’s interior
Energy is released mostly in the form of visible light and UV rays
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The appearance of stars from Earth depend on many factors…
How big the star is (magnitude), how bright it is (luminosity), its age, and how far away it is.
PROPERTIES OF STARS: DISTANCE Parallax
• Parallax is the slight shifting of the apparent
position of a star due to the orbital motion of
Earth (we’re moving - they’re not)
• The nearest stars have the largest parallax
angles, while those of distant stars are too small
to measure.
A larger star may appear smaller or dimmer from Earth if it is further away than a much smaller star that is closer to us.
Light-Year
• A light-year is the distance light travels in a year,
about 9.5 trillion kilometers.
PARALLAX
PARALLAX SHIFT
Original Photo
Photo taken 6 months later
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PROPERTIES OF STARS: BRIGHTNESS Apparent Magnitude
• Apparent magnitude is the brightness of a star
when viewed from Earth.
• Three factors control the apparent brightness of
a star as seen from Earth: how big it is, how hot
it is, and how far away it is.
Absolute Magnitude
• Absolute magnitude is the apparent brightness
of a star if it were viewed from a distance of 32.6
light-years.
PROPERTIES OF STARS: LUMINOSITY AND TEMPERATURE
Luminosity – measures how bright a star would be compared to our Sun if all stars were at the same distance from an observer
• Luminosity and temperature are used to describe stars
The Luminosity and Temperature of Stars Diagram is used to plot and understand stars (ESRT pg. 15)
PROPERTIES OF STARS: BRIGHTNESS & LUMINOSITY
A Hertzsprung–Russell diagram shows the
relationship between the absolute magnitude and
temperature of stars.
A main-sequence star, such as our Sun, is the
average temperature and brightness of a star
about half way through its life cycle.
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Reference Table Page 15
HERTZSPRUNG–RUSSELL DIAGRAM
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Giant stars
TYPES OF STARS
 around 10 times the diameter of the Sun  higher luminosity than the Sun  relatively low temperature
 late stage of small to medium sized stars
Main sequence stars
 medium sized stars like our Sun
 109 times the size of earth
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Super giant stars
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White dwarfs
 100 to 1000 times the diameter of the Sun
 brightest stars  late evolution stage of large stars
 explode in events called supernova
 not all are white  around the size of earth  hot on surface
 low in luminosity
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Black dwarfs
 dead stars  white dwarfs that have emitted all their energy
 no longer undergo nuclear fusion
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STELLAR EVOLUTION
All stars, regardless of their size, eventually run out
of fuel and collapse due to gravity.
Death of Low-Mass Stars
• Stars less than one-half the mass of the sun never
evolve to the red giant stage but remain in the
stable main-sequence stage until they consume
all their hydrogen fuel and collapse into a white
dwarf.
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STELLAR EVOLUTION
LIFE CYCLE OF A SUN‐LIKE (MAIN SEQUENCE) STAR
Death of Medium-Mass Stars
• Stars with masses similar to the sun evolve in
essentially the same way as low-mass stars.
• During their collapse from red giants to white dwarfs,
medium-mass stars are thought to cast off their outer
layer, creating an expanding round cloud of gas called
planetary nebula.
• Then, they become a white dwarf, and eventually a
black dwarf.
• See next 2 slides for Life Cycles of Main Sequence &
Supergiants)
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NEBULA, BIRTHPLACE OF STARS
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PLANETARY NEBULA
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SUPERNOVA SUPERNOVA SUPERNOVA THE SOLAR SYSTEM ORBITS OF THE PLANETS
The Terrestrial planets are planets that are small and rocky—Mercury, Venus, Earth, and Mars.
The Jovian planets are the huge gas giants—Jupiter, Saturn, Uranus, and Neptune
Pluto does not fit into either the Jovian or the terrestrial category.
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THE SOLAR SYSTEM SOLAR SYSTEM DATA: ESRT PG. 15 Size is the most obvious difference between
the terrestrial and Jovian planets.
Density, chemical makeup, and rate of rotation are other ways in which the two groups of planets differ.
THE SOLAR SYSTEM SCALE OF THE PLANETS
The Interiors of the Planets
• The substances that make up the planets are divided into three groups: gases, rocks, and ices.
The Atmosphere of the Planets
• The Jovian planets have very thick atmospheres of hydrogen, helium, methane, and ammonia.
• By contrast, the terrestrial planets, including Earth, have meager atmospheres at best.
FORMATION
FORMATION OF THE UNIVERSE
Nebular Theory
• A nebula is a cloud of gas and/or dust in space.
• According to the nebular theory, the sun and planets formed from a rotating disk of dust and gases.
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THE TERRESTRIAL PLANETS: MERCURY MERCURY’S SURFACE
Mercury is the innermost and second smallest
planet; it is hardly larger than Earth’s
moon.
Surface Features
• Mercury has cratered highlands, much like the moon, and vast smooth terrains
Surface Temperatures
• Mercury has the greatest temperature extremes of any planet.
THE TERRESTRIAL PLANETS: VENUS Surface Temperatures
• The surface temperature of Venus reaches 475oC, and its atmosphere is 97 percent carbon dioxide.
VENUS
VENUS
Venus is similar to Earth in size, density, mass, and location in the solar system. Thus, it has been referred to as “Earth’s twin.”
Surface Features
• Venus is covered in thick clouds that visible light cannot penetrate.
• About 80 percent of Venus’s surface consists of plains covered by volcanic flow.
THE TERRESTRIAL PLANETS: MARS The Martian Atmosphere
• The Martian atmosphere is very thin; has only 1 percent of the density of Earth’s.
• Extensive dust storms occur and may cause the color changes observed from Earth.
Surface Features
• Rocky & cratered; probably 3.5 billion to 4.5 billion years old.
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MARS
THE TERRESTRIAL PLANETS Water on Mars
• Some areas of Mars exhibit drainage patterns similar to those created by streams on Earth.
• Images from the Mars Global Surveyor indicated groundwater
• On September 28, 2015, NASA announced that Mars Reconnaissance Orbiter (MRO) provide the strongest evidence yet that liquid water flows intermittently on present‐day Mars.
WATER ON MARS
THE OUTER PLANETS: JUPITER WATER ON MARS
JUPITER AND THE GREAT RED SPOT
Jupiter has a mass that is 2 1/2 times greater than the mass of all the other planets and moons combined.
Structure of Jupiter
• Jupiter’s hydrogen‐helium atmosphere also contains small amounts of methane, ammonia, water, and sulfur compounds.
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THE OUTER PLANETS JUPITER’S LARGEST MOONS
Jupiter’s Moons
• Has 28 moons (discovered so far)
Jupiter’s Rings
• Jupiter’s ring system was one of the most unexpected discoveries made by Voyager 1.
THE OUTER PLANETS: SATURN CASSINI APPROACHING SATURN
The most prominent feature of Saturn is its system of rings.
Features of Saturn
• Saturn’s atmosphere is very active, with winds roaring at up to 1500 kilometers per hour.
• Large cyclonic “storms
THE OUTER PLANETS Saturn’s Rings
SATURN’S RINGS
• Until the discovery that Jupiter, Uranus, and Neptune have ring systems, this phenomenon was thought to be unique to Saturn.
• Most rings fall into one of two categories based on particle density.
Saturn’s Moons
• Consists of 31 moons.
• Titan is the largest moon, and it is bigger than Mercury.
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THE OUTER PLANETS: URANUS URANUS
Uranus’s axis of rotation lies nearly parallel with the plane of its orbit (it’s sideways)
THE OUTER PLANETS: NEPTUNE NEPTUNE
Neptune: The Windy Planet
Winds exceeding 1000 kilometers per hour encircle Neptune, making it one of the windiest places in the solar system.
THE OUTER PLANETS: PLUTO Pluto’s orbit is highly eccentric, causing it to
occasionally travel inside the orbit of
Neptune, where it resided from 1979
through February 1999.
MINOR MEMBERS OF THE SOLAR SYSTEM An asteroid is a small, rocky body whose
diameter can range from a few hundred
kilometers to less than a kilometer.
Most asteroids lie between the orbits of Mars
and Jupiter.
They have orbital periods of three to six
years.
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IRREGULAR ORBITS OF ASTEROIDS
MINOR MEMBERS OF THE SOLAR SYSTEM Comets are small bodies made of rocky and metallic pieces held together by frozen gases. Comets generally revolve about the sun in elongated orbits.
COMETS
COMET’S TAIL POINTS AWAY FROM THE SUN
Coma
• A coma is the fuzzy, gaseous component of a comet’s head.
• A small glowing nucleus with a diameter of only a few kilometers can sometimes be detected within a coma. As comets approach the sun, some, but not all, develop a tail that extends for millions of kilometers.
MINOR MEMBERS OF THE SOLAR SYSTEM MINOR MEMBERS OF THE SOLAR SYSTEM Kuiper Belt
• Like the asteroids in the inner solar system, most Kuiper belt comets move in nearly circular orbits that lie roughly in the same plane as the planets.
Halley’s Comet
• The most famous short‐period comet is Halley’s comet. Its orbital period is 76 years.
Oort Cloud
• Comets with long orbital periods appear to be distributed in all directions from the sun, forming a spherical shell around the solar system called the Oort cloud.
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MINOR MEMBERS OF THE SOLAR SYSTEM A meteoroid is a small, solid particle that travels through space.
A meteor is the luminous phenomenon observed when a meteoroid enters Earth’s atmosphere and burns up, popularly called a shooting star.
A meteorite is any portion of a meteoroid that reaches Earth’s surface.
MINOR MEMBERS OF THE SOLAR SYSTEM Most meteoroids originate from any one of the following three sources: (1) interplanetary debris that was not gravitationally swept up by the planets during the formation of the solar system, (2) material from the asteroid belt, or (3) the solid remains of comets that once traveled near Earth’s orbit.
MAJOR METEOR SHOWERS
HOW DO PLANETS MOVE?
Planetary Orbits
Rotation – planets spin on an axis
Revolution – movement of an object around another object
Planets revolve around the Sun in an oval shape called an ellipse.
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ECCENTRICITY
ECCENTRICITY
The dictionary defines “eccentric” as:
Departing from a recognized, conventional, or established norm or pattern. See synonyms: strange. Deviating from a circular form or path, as in an elliptical
orbit.
*We sometimes use the term “eccentric” when we refer to something (or someone) who is a bit off, different, or abnormal.
WHAT DO ALL THOSE WORDS MEAN IN THAT EQUATION?
(d) Distance between foci (blue – the dots)
Eccentricity is used to express the shape of an elliptical orbit. It is almost never a complete circle, but just slightly oval.
Eccentricity = distance between foci
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length of major axis (longest axis)
(ESRT page 1)
IS MY MATH RIGHT? Eccentricity is a number between 0 and 1
Make sure your answer is rounded to the nearest thousandth (3 decimal places)!!!!!!!!!!!!!!!
ex: 0.408
This is one of the only calculations without units in this class!!
(L) Length of the major *You will measure these using a cm ruler
axis (red – the entire line across)
SHAPE OF ELLIPSES
Eccentricity = 0 circle
Eccentricity = 0.5
KEPLER’S THREE EMPIRICAL LAWS OF PLANETARY MOTION (WE WILL COVER 1 & 2)
1. The orbital paths of the planets are elliptical, with the Sun at one focus.
*The SUN is ALWAYS one of the foci or “dots”.
Eccentricity = 0.75
Eccentricity = 1 line
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KEPLER’S LAWS OF PLANETARY MOTION
2. Law
Areas:
of
Equal
An imaginary line
connecting the Sun
to any planet sweeps
out equal areas in
equal time..
GRAVITATIONAL EFFECTS OF VARYING THE DISTANCE TO THE SUN
The force of gravity is influenced by both mass and the distance from the sun.
1.
Greater the mass = greater the gravitational attraction
2.
Closer the 2 objects = greater the gravitational attraction
TO THE HUMAN EYE, MOST ORBITS OF PLANETS LOOK LIKE CIRCLES
SLIGHTLY ELLIPTICAL SHAPE OF EARTH’S ORBIT CAUSES THE PLANET TO VARY THE DISTANCE TO THE SUN DURING REVOLUTION 147 million
kms.
152 million
kms.
If mass stays the same but the distance varies, gravitational attraction will vary. If gravitational attraction varies, velocity will vary.
Perihelion = faster velocity
Aphelion = slower velocity
Perihelion = greater gravitational attraction
Aphelion = less gravitational attraction
(Aphelion – think, apart)
VELOCITY IS NOT CONSTANT DRAWING ELLIPSES
An important Earth Science lab requires you to draw an ellipse and calculate its eccentricity.
This is a section of you Part 1 Regents Exam (Lab Practical)
We will be completing a lab to prepare you for this exam.
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