Part 1 – Earth in the Universe Astr nomy

The Big Bang Video

The universe started with a concentrated area of matter and energy billion years ago. Then, it exploded and has been expanding ever since.

Matter began to clump together forming stars and galaxies. The universe continued to expand and is still expanding today.

Our Expanding Universe Video

Regents Question Which celestial feature is largest in actual size? (1) the Moon (2) the Sun (3) Jupiter (4) the Milky Way Answer is… 4

How do we know the universe is expanding? Pg. 14 in the ESRT shows the electromagnetic spectrum. Notice that in the visible spectrum there are all the colors of the rainbow.

Please answer the questions on the Electromagnetic spectrum ½ sheet.

When looking at the visible spectrum wavelengths are shifted either to the blue end (shorter wave) or the red end (longer wave). This shift in wavelengths is called the Doppler Effect. If they are shifted towards red, they are moving away from you. If they are shifted toward blue, they are coming towards you.

When scientists look at the universe, they see a red shift. This proves it is moving away from us, thus, expanding!

A Quick look at the Doppler Affect Using a police car

Another look at the Doppler Affect using sound

Light from galaxies moving away Earth Science Rocks Notice the shift towards red

Light from galaxies moving toward us Earth Science Rocks Notice the shift towards blue.

A galaxy is a collection of billions of stars and gas and dust. Our solar system is part of the Milky Way Galaxy. The Milky Way is a spiral-shaped galaxy.

Regents Question The Milky Way Galaxy is best described as (1) elliptical (2) circular (3) irregular (4) Spiral Answer is… 4

A star is usually a large ball of gas held together by gravity. Energy is produced by nuclear fusion – combination of nuclei of smaller elements to form nuclei of larger elements. Earth Science Rock

Regents Question Which star color indicates the hottest star surface temperature? (1) blue (2) yellow (3) white (4) Red

The good news!! This is all for free on pg. 15 of the ESRT!

Regents Question Which star color indicates the hottest star surface temperature? (1) blue (2) yellow (3) white (4) Red Answer is… 1

Regents Question In the main sequence, compared to the surface temperature and luminosity of massive stars, the smaller stars are (1) hotter and less luminous (2) hotter and more luminous (3) cooler and less luminous (4) cooler and more luminous Answer is… 3

Life and Death of a Star Video Clip

Take out ESRT- Page 15

1.What is the most massive star on the chart? ________________________________ 2. What is the temperature and luminosity of the Sun? __________________ and ________________ 3. What group is a star in during a late stage? ________________________________ DENEB 5,600 ºK Luminosity = 1 White Dwarfs

Page 15

4. What is the temperature and luminosity of Betelguese? ___________________ and ___________________ 5. What color would a star be if it was 15,000ºK? ________________________________ 6. What group of star is Albebaran in? ________________________________ Giants Blue White 3300ºK 200,000

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7. What temperature and color is Proxima Centauri? __________________ and __________________ 8. Massive stars are (more / less) luminous. (Circle one) 9. Name a White Dwarf star. __________________ 10. What stage are Main Sequence stars in? _______ Procyon B or Eridani B Early 2800ºKRed

The solar system is the sun and all objects that orbit the sun under its gravitational influence. Our solar system has 1 sun and 8 planets.

Regents Question The Sun’s position in space is best described as the approximate center of (1) a constellation (2) the universe (3) the Milky Way galaxy (4) our solar system Answer is… 4

Regents Question Compared to Earth’s solar system, the universe is inferred to be (1) younger and larger (2) older and larger (3) younger and smaller (4) older and smaller Answer is… 2

Pluto? New Chart in your ESRT… Sorry Pluto…

Using the data table on page 15 of your ESRT, answer the following questions. 1. What is the period of rotation of Mercury? _____________________________ 2. What is a year on Mars?__________________________________________ 3. Which planet has the most eccentric orbit? ___________________________ 4. Which has the least eccentric orbit? ____________________________ 5. What is the diameter of Jupiter?__________________________ 6. What is a day on Saturn?__________________________________________ 59d 687 d Mercury Venus 142,984 km 10 h 14 min

7. Which planet has the longest period of rotation?__________The shortest?_________ 8. Which planet is the most dense?_____________The least?____________ 9. How far from the sun is Venus?__________________ 10. How far from Earth is our Moon?______________________________________ 11. What is the mass of Neptune ?____________________ 12. What is the radius of Saturn?_______________________________ Venus Jupiter Earth Saturn million km million km 4,498.3 million km 60,268 km

Regents Question Which event takes the most time? (1)one revolution of Earth around the Sun (2) one revolution of Venus around the Sun (3) one rotation of the Moon on its axis (4) one rotation of Venus on its axis Answer is… 1

An ellipse is an oval shape. Earth’s orbit around the sun is an ellipse. Within an ellipse, there are two fixed points called foci. In our solar system, the sun is ALWAYS ONE of those foci.

The degree of flatness or “ovalness” of an ellipse is measured by eccentricity. This formula is on page 1 of your ESRT!

The more oval the orbit is, the more eccentric it is, or the higher the eccentricity. Increasing Eccentricity

Calculating Eccentricity: XX Major Axis Foci 1 Foci 2

You can make an ellipse with 2 tacks and a string. The tacks are the “foci”, and if you put them further apart, the ellipse is more “eccentric” (one tack makes a circle). An ellipse is an example of a “conic section”. Circles and hyperbolas are others. All are possible forms for orbits.

Calculating Eccentricity: When you measure those 2 distances and calculate them, you will NEVER get higher than 1!! The closer to 1 you are the MORE oval or eccentric the orbit. The closer to 0 you are the LESS oval or eccentric the orbit.

Regents Question Which planet’s orbit around the Sun is most nearly circular? (ESRT 15) (1) Mercury (2) Pluto (3) Neptune (4) Venus Answer is… 4 No More Pluto 

The closer 2 objects are to each other, the greater the gravitational pull between them. Therefore, during the perihelion – when Earth is closer to the sun, there is a greater gravitational pull between it and the sun. This makes the Earth speed up a bit in its orbit around the sun during that time.

PerihelionAphelion Earth Science Rocks

What do you notice about the planets orbital velocity? Aphelion Perihelion Planets move quicker the closer they are to the Sun

Kepler’s Second Law

Regents Question Compared to Neptune, Mercury moves more rapidly in its orbit because Mercury (1) is larger (2) is more dense (3) is closer to the Sun (4) has a more elliptical orbit Answer is… 3

Write the formula for eccentricity below: Calculate the eccentricity of the ellipse. Distance between foci: ______________ Length of major axis: ______________ Eccentricity= ______________ X Page 1 of ESRT’s length of Major Axis Distance between foci 8.8cm 6.4cm.72

Calculate the eccentricity of the ellipse. Distance between foci: ______________ Length of major axis: ______________ Eccentricity= ______________ X Length of Major Axis Distance between foci 5.4cm 1.3cm.24

What is the minimum value that eccentricity can be? ________ 0.99 What is the maximum value that eccentricity can be? _______ Doesn’t a circle look like a zero???? The more eccentric the more stretched out until you get a straight line Look the # one.