How can a collision between galaxies produce a starburst galaxy? Discuss two observations that seem to indicate that clusters of galaxies are embedded in huge halos of dark matter.

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Chapter 17 and 18

Assignment 9: Chapters 17 and 18 // Due 11/12 [1] (10 points) Short answer questions: (a) Name a galaxy besides our own that can be seen with the naked eye?
(b) What do astronomers attribute the ring of the cartwheel galaxy to?
(c) About how many times more luminous are powerful quasars compared to the Sun?
(d) About how many times more luminous are powerful quasars compared to a galaxy like the MW? (Hint: The Milky Way (MW) shines with about 20 billion solar luminosities) (e) Why were astronomers originally led to believe that the energy producing region of a quasar must be small? (f) About how many solar masses is the Supermassive black hole in the giant elliptical galaxy M87 in the center of the Virgo Cluster of galaxies? (g) Where are giant elliptical galaxies found.
(h) How did giant elliptical galaxies get so massive?
(i) Name two very reliable standard candles for determining distances to galaxies.
[2] (10 points) How can a collision between galaxies produce a starburst galaxy? (Explain thoroughly)
[3] (10 points) Discuss two observations that seem to indicate that clusters of galaxies are embedded in huge halos of dark matter. (be specific give details)
[4] (10 points) Explain how supernovae type la are utilized to measure Hubble’s constant? Why are measurements of the redshifts of the galaxies that host the Supernovae type la just as important? Think Hubble’s law. (Explain thoroughly)
[5] (10 points) Distant galaxies have a dominant recessional velocity dictated by the expansion of the universe. If Hubble’s constant is 71 (km/sec)/Mpc, how far away is a galaxy receding at 8.88 x 103 km/sec? Hint: See Astronomer’s Toolbox 17-1 page 573.
Extra Points (8 points) Centaurus A lies at a distance of 4 Mpc from Earth. This galaxy has radio jets that span across the sky –from the end of one lobe to the end of the other lobe — with an angular diameter equivalent of 28.5 full moon widths. If the jets are equal in length how long is one of them in parsecs? Hint: one full moon is .5 degrees in angular diameter. Once you get the angular length of the jets in degrees convert to radians and use the arclength formula s = r 19„d to find the length ‘s’ of both jets in Mpc. Then convert to find the length of one jet in parsecs. (Show all work)

How long is a day for Jupiter’s equatorial clouds? What temperature is thought to exist in the core of Jupiter? What is the height of the cliff on Miranda (small moon of Uranus)? What moon of Saturn is shaped like a walnut (with a giant equatorial ridge)?

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 Chapters 9 and 10


[1] Short Answer Questions (10 points; 1 point for each lettered subheading):

(a) How long is a day for Jupiter’s equatorial clouds?

(b) What temperature is thought to exist in the core of Jupiter?

(c) What is the height of the cliff on Miranda (small moon of Uranus)?

(d) What moon of Saturn is shaped like a walnut (with a giant equatorial ridge)?

(e) How many Earths would span Jupiter’s largest storm (the Great Red Spot)?

(f) Which planet has a mysterious hexagonal pattern of clouds surrounding its north pole?

(g) Which planet has an extreme spin axis tilt (axis lies within 8 degrees of the plane of orbit)?

(h) What planet has an average density less than water?

(i) What planet has the strongest magnetic field in the solar system?

(j) What moon (of what planet) exhibits active geysers of liquid Nitrogen?

[2] Long answer exercise (10 points)
Discuss in some detail three unique features of Titan, moon of Saturn (not its size).

[3] Long answer exercise (10 points)
Explain all the causes and conditions that heat Europa’s interior, resulting in an ocean of water under a
thick ice sheet. Europa’s ocean is potentially a habitat for alien aquatic life!
FYI: Similar processes are thought to cause Io’s active volcanoes.

[4] Long answer exercise (10 points)
Why is Triton (the largest moon of Neptune) spiraling in toward Neptune?
Why will Triton never collide with Neptune. (Explain thoroughly).

[5] “Two Sentence Answer” Questions (10 points; 2 points for each lettered subheading):

(a) What causes the Cassini Gap in the rings of Saturn? See figure 9–29.

(b) What causes the Kirkwood Gaps in the asteroid belt?

(c) Describe Oumuamua’s trajectory.

(d) What evidence supports the speculation that Enceladus (a moon of Saturn) might harbor life.

(e) Describe the strange behavior of Saturn’s co–orbiting satellites: Janus and Epimetheus.

[Extra Points] Long answer exercise. (8 points)
Where are the Greek and Trojan asteroids located? Draw a diagram. Why are there asteroids in these
locations? (See Canvas/Pages/(11) Greek, Trojan, and Hilda asteroids) (See Figure 10–21 page 333).

Explain the hydrostatic equilibrium within a star. If a star were to accumulate more mass from say gas transfer from a close binary companion star describe in detail the way the mass receiving star would respond in order to maintain hydrostatic equilibrium? How would the donor star respond to maintain equilibrium?

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Chapter 11 and 12

[1] Short Answer Questions (10 points; 2 points for each lettered subheading):

(a) What is the temperature of the Sun at its surface?

What is the temperature of the Sun at its core?

(b) What type (frequency) of photon is generated at the core of the Sun.

How long between the polarity reversals (pole flips) of the Sun’s magnetic field?

(c) How long does it take the Sun to Rotate once around at the equator?

How long does it take the Sun to Rotate once around at the poles?

(d) The Sun generates energy by fusing what into what?

Approximately, how much longer before the Sun swells and cooks Earth.

(e) How long does it take the radiant energy generated in the Sun’s core to migrate to the surface
of the Sun?

How many Earths would line up end to end across the diameter of the Sun? Do not google it!
(Hint: Divide the radius of the Sun by the radius of the Earth in the same units). Voila!

[2] (10 points)
Describe thoroughly the Proton – Proton chain of fusion by which the Sun generates radiant energy
through the production of 𝛾- ray photons deep in the core. Show all the steps.
Hint: This question is answered for you completely in animation 11.1 page 383.

[3] (10 points)
Explain the hydrostatic equilibrium within a star. If a star were to accumulate more mass from say gas
transfer from a close binary companion star describe in detail the way the mass receiving star would
respond in order to maintain hydrostatic equilibrium? How would the donor star respond to maintain
equilibrium?

[4] (10 points)
Describe a Hertzsprung-Russell diagram.
What is plotted vertically?
What is plotted horizontally?
Because of Wein’s law, what is (equivalently) plotted horizontally?
Where are the largest radius stars located on an HR diagram?
Where are the smallest radius stars located on an HR diagram?

As you progress along the main sequence from the lower right to the upper left:
How does stellar mass change?
How does stellar life expectancy change?

[5] (10 points)
Two stars orbit with period of 915 days. They are separated by 6.05×10^8 km. What is their combined
mass?
Hint: See Astronomer’s Toolbox 12-4 page 412.
Hint: 1 𝑎𝑢 = 1.5 × 10! 𝑘𝑚.
(show all work)

[Extra Points] (5 points)
Use the inverse square law for light intensity to find the luminosity for the star Antares, given that its
known distance from parallax measurements is 170 parsecs, and its intensity measured at Earth is
8.4 × 10″!𝑊/𝑚#.

1 𝑃𝑎𝑟𝑠𝑒𝑐 = 3.086 × 10$% 𝑚𝑒𝑡𝑒𝑟𝑠

Hint: See Canvas/Modules/Chapter 11 and 12/Standard Candles and the Inverse Square Law.

𝐼 = 𝐿
4𝜋𝑑#

How many times more luminous is Antares than our Sun?

[Bonus Extra points] (5 points)
Sirius (A) has white dwarf companion star Sirius (B). The system is known to have a semi-major axis of 20
au and a period of 50 years. Doppler shifts show that at any given time Sirius (B) moves twice as fast as
Sirius (A). What is the mass of Sirius (A)? What is the mass of Sirius (B)?
Hint: conservation momentum requires that 𝑚&𝑣&= 𝑚’𝑣’. Solve for the ratio of the masses.
Kepler’s third will yield the sum of the masses of the two stars. Together you can find the mass of each
star.

How do the radiogenic ages of the samples brought back by Apollo 11 and 12 compare to the “typical” ages of rocks from the Earth?

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How do the radiogenic ages of the samples brought back by Apollo 11 and 12 compare to the “typical” ages of rocks from the Earth?

Write a 750 word Speech on why America as a country should invest in fundamental research about our universe.

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You have been called before congress. Lawmakers from every part of the
country, representing constituents from all walks of life, are asking you to
give a speech on why the country should invest in basic science/astronomy
research.
Write a 750 word Speech on why America as a country should invest in
fundamental research about our universe. Think about including
technological off shoots of telescopes/satellites/rockets. Think about the
potential future rewards of space travel. Speak to the very nature of
humanity as a curious and exploring creature. Talk about beauty, wonder,
economics, power, the serendipity of finding useful discoveries in
unexpected places…. Be creative and in a sense, use what you learned in
this class to justify to the American people why Astronomy matters.

Discuss The Astronomical Significance of Gobekli Tepe.

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Discuss The Astronomical Significance of Gobekli Tepe

Paragraph 1: Describe the temple. Give its location, the date it was constructed, what it contains, its dimensions, what it is made of, etc. (In this paragraph, include only the facts regarding the physical attributes of the structure.) Include these words: circular, pillar, weight, height, limestone

Paragraph 2: Describe what the researchers think the temple was used for, what the temple’s symbols may represent, what event or events the symbols may have depicted, etc. (In this paragraph, include only the researchers’ ideas and constructs. Do NOT include why the researchers proposed their hypothesis. Simply state what they think they have found.) Include these words: observatory, meteor, carving, asterism

Paragraph 3: Describe the evidence the researchers point to that supports their hypothesis. Focus on the astronomical evidence. Why do the researchers think their ideas are plausible ones? (This is where you will explain briefly the researchers’ reasons for making their assertions.) How did the astronomical event affect human history? Include these words: comet, computer, Younger Dryas, Greenland

What’s the star’s mass and what is the planet’s orbital eccentricity?

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Go to the online “Extrasolar Planets Encyclopedia” (Links to an external site.) Link:

Find a planet with an orbital period similar to that of Earth. What is the planet’s name and its semimajor axis of of its orbit? If it is very different from 1 AU, then the mass of the star is different from that of the Sun. Click on the star name in the first column to see the star’s mass. What’s the star’s mass and what is the planet’s orbital eccentricity?

Click on “Planet” to sort by name, and select a star with multiple planets. Mention the star’s name and its planets. Verify that Kepler’s third law applies by showing that the value P2/A3 is about the same for at least two of the planets of this star. How eccentric are the orbits of the multiple planets? (Remember the orbital period needs to be in years to do the simple calculation!)

What challenges did you encounter when doing the work?

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This laboratory project involves conducting research – that is, contributing to a major science project being conducted by professional scientists – and writing a formal lab report about the work you’ve done.  Both tasks are important in science, because once you learn something new and interesting about the universe, you need to let people know about it with clear prose and in a recognizably standard format.

Please read the instructions and explanations carefully. Use the Report Template pages at the end of this document to write your report; those are the pages you will turn in.

INSTRUCTIONS

Step 1

(a) go to the Zooniverse website and learn about the SuperWASP (zooniverse.org/projects/ajnorton/superwasp-variable-stars) project.  Your instructor may point you to another Zooniverse project – follow your instructor’s lead on this, please.

(b) Register as a volunteer researcher for the appropriate Zooniverse project.

(c) Look at the Report Template pages to see the kinds of things you will be including in your written report.  Then, taking detailed notes on the things you need to include, participate in the project’s research activities for approximately 45-60 minutes.  You may work in parallel with other members of the class – be sure to write down their first names, last names, and email addresses

Step 2

Follow the Report Template pages and write a clear, thorough report of your Zooniverse research activity.  On the first page, draw a picture in the circle that will help you illustrate the work you’ve done on this project, and write a caption explaining what the figure is showing and other relevant information.

Results:

How long did you conduct this work?

How many pieces of data did you examine?

What were the results you obtained – how many of what kind?

Discussion:

What went well with the work you conducted?

What challenges did you encounter when doing the work?

Do you think your work was successful, believable, dubious, or otherwise?  Why?

Conclusion:

Summarize what you did overall in a sentence or two.

Summarize your results in a sentence or two.

Summarize the key points of your discussion in a sentence or two.

Write another sentence or two about what you feel you’ve learned and your overall experience conducting this work, and about what might happen in the future regarding this Zooniverse project.

 

Explore what happens when the process of scientific thought is either negligently or maliciously derailed

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In the paper, explore what happens when the process of scientific thought is either negligently or maliciously derailed(when scientific thought is wrong)

Can a satellite maintain an orbit in the plane of the Arctic Circle?

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Can a satellite maintain an orbit in the plane of the Arctic Circle? Why or why not?

style type is not needed