Categories
Astronomy

Ch. 8 study questions

Ch. 8 Study Questions
1. There are several reasons it is hard to see details on Mercury, from the Earth. Name at least one. More if you want to show off.
2. What is unusual about Mercury’s iron core?
3. Something unusual happened on the exact opposite side of Mercury, from the Caloris Basin. What was it?
4. Mercury almost keeps the same side baking in the Sun all the time, but not quite. How many times does Mercury rotate per two trips around the Sun?
5. Why is Venus sometimes called Earth’s sister planet?
6. Venus is not the closest planet to the Sun, so why is it the hottest?
7. What is the most prominent type of surface features on Venus?
8. What is unusual about Venus’s rotation?
9. We can’t see through Venus’s clouds, so how have we obtained detailed images of its surface?
10. What color is Mars?
11. In what physical state is water known to exist on Mars?
12. What is the name of the highest mountain in the solar system?
13. What is the name of the longest, deepest, widest canyon in the solar system?
14. What are the polar caps on Mars made of?
15. Mars does not have enough atmosphere to support liquid water, yet Mars has gigantic dry river beds. What must have been true on Mar’s in the past?

Categories
Astronomy

Explain.

1. Suppose Eratosthenes had found that, in Alexandria, at noon on the first day of summer, the line to the Sun makes an angle 30° with the vertical. What, then, would he have found for Earth’s circumference?
2. Suppose you are on a strange planet and observe, at night, that the stars do not rise and set, but circle parallel to the horizon. Next, you walk in a constant direction for 8000 miles, and at your new location on the planet, you find that all stars rise straight up in the east and set straight down in the west, perpendicular to the horizon. How could you determine the circumference of the planet without any further observations? What is the circumference, in miles, of the planet?
3. Ursa Minor contains the pole star, Polaris, and the asterism known as the Little Dipper. From most locations in the Northern Hemisphere, all of the stars in Ursa Minor are circumpolar. Does that mean these stars are also above the horizon during the day? Explain.
4. How many degrees does the Moon move per day relative to the fixed stars? How many days does it take for the Moon to return to its original location relative to the fixed stars?
5. If a star rises at 8:30 p.m. tonight, approximately what time will it rise two months from now

Categories
Astronomy

Learning goal: i’m working on a astronomy writing question and need an explanation and answer to help me learn.

Learning Goal: I’m working on a astronomy writing question and need an explanation and answer to help me learn.
All the information are in the document, please read it before you do the assignment.

Categories
Astronomy

Tangent 20 = 0.364

Learning Goal: I’m working on a astronomy discussion question and need an explanation and answer to help me learn.
In this assignment you will use your inclinometer to find the height of a building, a tree, and a telephone pole. Something similar can be done to find diameters of planets. You don’t have the equipment necessary to actually find the diameters of planets, but you can learn about the technique by determining heights of everyday objects on Earth.
You are going to find the angle between the horizon and the top of the building. Do it the same way you found the elevation of the Sun. Point the edge of the protractor at the top of the building, and read off the number of degrees between the string and the 90 degree mark on the protractor.
Let’s say the angle is 35 degrees. The height of the building equals the sine of 35, times the distance to the building, thus: height = tangent (35) x distance.
The tangent is an example of a trig function. Those of you who have taken algebra II are acquainted with trig functions (for better or worse). You don’t need to know what they are in order to do this project.
I will calculate the tangent of a range of angles for you:
tangent 10 = 0.176
tangent 15 = 0.268
tangent 20 = 0.364
tangent 25 = 0.466
tangent 30 = 0.577
tangent 35 = 0.700
tangent 40 = 0.839
tangent 45 = 1.0
45 degrees is the largest angle I want you to use. If your angle is bigger than 45, back up. Adjust your distance from the building until the angle from the horizon to the top of the building is one of the numbers in the list. 25 or 30, for example, rather than 28.
To calculate the height of the building, you also need the distance to the building. The most accurate method to get the distance is to use a tape measure. If not that, you could measure the length of your shoe, and walk heel to toe from your angle-measuring position, to the building, counting the little baby steps. Multiply the length of your shoe by the number of baby steps, to get the distance to the building. Worst of all, you can measure the length of a full stride, and count the steps to the building. The more accurate your distance to the building, the more accurate the calculated height.
Example:
The measured angle between the horizon and the top of the building is 35 degrees. The length of my shoe is 11 inches. After measuring the angle, I walked 90 baby steps to the building. 90 x 11 inches = 990 inches. 990 inches / 12 inches per foot = 82.5 feet.
h = tangent (35) x d
h = 0.700 x 82.5 feet
h = 57.8 feet
57.8 feet is actually how high the top of the building is above your eyeballs. How high is the top of the building above the ground? You figure it out.
Do this two more times, for a tree, and for a telephone pole.
Show all arithmetic operations, or NO CREDIT. Plus, I can’t give you feedback if I can’t see what you did.

Categories
Astronomy

2) the big dipper appears somewhat like a plow when viewed from the earth.

Learning Goal: I’m working on a astronomy question and need an explanation and answer to help me learn.
1) The stars that make up the Big Dipper appear close to each other when we look up at the night sky. However, are the stars that make up the Big Dipper actually physically clustered around the same region of space? Explain in your own words (just a few sentences) why the stars appear to be close to each other when in reality they might not actually be close to each other.
2) The Big Dipper appears somewhat like a plow when viewed from the Earth. Imagine you are an alien who lives on another planet orbiting a different star in our Galaxy. If you looked up at the night sky at the same set of stars that make up the Big Dipper, would the shape still necessarily look like a plough? Why or why not? Explain your answer in a few sentences.

Categories
Astronomy

Learning Goal: I’m working on a astronomy exercise and need an explanation and a

Learning Goal: I’m working on a astronomy exercise and need an explanation and answer to help me learn.
General instructions for assignments
All responses must be typed.
All calculations must be shown in full.
All graphs must be electronically produced.
All references must be cited using Chicago Manual of Style conventions.
Sharing of phrasing or formatting with other students is prohibited.
This work is the intellectual property of the instructor and Washington State University. All reproduction or retransmission in whole or in part is strictly prohibited.
Ref: Spectrum constructor (Foothill College astronomy simulations)
https://foothillastrosims.github.io/Spectrum-Constructor/ (Links to an external site.)
The purpose of this assignment is to recognize the three different types of spectrum, and explain how spectral lines are used to identify uniquely an atom or molecule in a source of light.
Navigate to the Spectrum Constructor simulation linked above. Recognize the parts of the display: the “eyeball view” is what your eye would see when unaided. The “diffraction grating view” is what your eye would see after the light is passed through a raindrop, cut gemstone, or any other agent that separates light into its constituent colors. The “spectrometer view” is a graph of brightness (vertical axis) vs color (horizontal axis).
The diffraction grating view and spectrometer view are aligned vertically by wavelength. Wavelength is measured in nanometers (nm, 10-9 meters).
Part 1: continuous spectrum
Begin with the sim in its default state: the visible spectrum is checked on, the speed is 0 km/s, and all other boxes are unchecked. What you see is called a continuous spectrum. Write a few sentences of description of the diffraction grating view; of the spectrometer view. For example, you might say that in the diffraction view all colors are present, and in the spectrometer view you might say that all colors are at the same brightness (same level on the y-axis).
Part 2: emission line spectrum
Select Continuous spectrum: None. Select several atoms from within the Emission spectra box. Describe the changes on the diffraction grating view, and the changes on the spectrometer view. Each bright shade of color that appears is called an emission line. Do any two atoms have the identical set of emission lines? Some of these lines are quite famous: the bright red line of hydrogen at 656 nm is the red color we see in interstellar clouds, and the double yellow line of mercury near 580 nm is found in fluorescent bulbs.
Part 3: absorption line spectrum
Select Continuous spectrum: Visible. Uncheck all emission lines. Select several atoms from within the Absorption spectra box. Describe the changes on the diffraction grating view, and the changes on the spectrometer view. Each missing shade of color is called an absorption line, because light is being absorbed (removed) from the spectrum. Is the continuous spectrum necessary for us to see absorption lines? Do any two atoms have the identical set of absorption lines?
Part 4: general questions
If an atom has an emission line at a given shade of color (e.g., hydrogen at 656 nm), then does that atom have an absorption line at that same shade of color?
Use the slider button under the label km/s to change the speed of the glowing object: negative speeds for objects approaching us, and positive speeds for objects recessing from us. Describe changes to each of the continuous spectrum, emission line spectrum, and absorption line spectrum as the speed changes. This change is called the Doppler effect, and is essential for measuring the speeds of objects located at a distance.
Suppose you were given a spectrum of a planet. The spectrum has a collection of absorption lines. Describe how you would use this simulation to identify what lines were present (or absent) in the spectrum, and therefore what atoms were present (or absent) on the planet.
Grading: all questions are weighted equally. Total points = [30].
Do not need a title page

Categories
Astronomy

Learning Goal: I’m working on a astronomy exercise and need an explanation and a

Learning Goal: I’m working on a astronomy exercise and need an explanation and answer to help me learn.
General instructions for assignments
All responses must be typed.
All calculations must be shown in full.
All graphs must be electronically produced.
All references must be cited using Chicago Manual of Style conventions.
Sharing of phrasing or formatting with other students is prohibited.
This work is the intellectual property of the instructor and Washington State University. All reproduction or retransmission in whole or in part is strictly prohibited.
Ref: Spectrum constructor (Foothill College astronomy simulations)
https://foothillastrosims.github.io/Spectrum-Constructor/ (Links to an external site.)
The purpose of this assignment is to recognize the three different types of spectrum, and explain how spectral lines are used to identify uniquely an atom or molecule in a source of light.
Navigate to the Spectrum Constructor simulation linked above. Recognize the parts of the display: the “eyeball view” is what your eye would see when unaided. The “diffraction grating view” is what your eye would see after the light is passed through a raindrop, cut gemstone, or any other agent that separates light into its constituent colors. The “spectrometer view” is a graph of brightness (vertical axis) vs color (horizontal axis).
The diffraction grating view and spectrometer view are aligned vertically by wavelength. Wavelength is measured in nanometers (nm, 10-9 meters).
Part 1: continuous spectrum
1. Begin with the sim in its default state: the visible spectrum is checked on, the speed is 0 km/s, and all other boxes are unchecked. What you see is called a continuous spectrum. Write a few sentences of description of the diffraction grating view; of the spectrometer view. For example, you might say that in the diffraction view all colors are present, and in the spectrometer view you might say that all colors are at the same brightness (same level on the y-axis).
Part 2: emission line spectrum
1. Select Continuous spectrum: None. Select several atoms from within the Emission spectra box. Describe the changes on the diffraction grating view, and the changes on the spectrometer view. Each bright shade of color that appears is called an emission line. Do any two atoms have the identical set of emission lines? Some of these lines are quite famous: the bright red line of hydrogen at 656 nm is the red color we see in interstellar clouds, and the double yellow line of mercury near 580 nm is found in fluorescent bulbs.
Part 3: absorption line spectrum
1. Select Continuous spectrum: Visible. Uncheck all emission lines. Select several atoms from within the Absorption spectra box. Describe the changes on the diffraction grating view, and the changes on the spectrometer view. Each missing shade of color is called an absorption line, because light is being absorbed (removed) from the spectrum. Is the continuous spectrum necessary for us to see absorption lines? Do any two atoms have the identical set of absorption lines?
Part 4: general questions
1. If an atom has an emission line at a given shade of color (e.g., hydrogen at 656 nm), then does that atom have an absorption line at that same shade of color?
2. Use the slider button under the label km/s to change the speed of the glowing object: negative speeds for objects approaching us, and positive speeds for objects recessing from us. Describe changes to each of the continuous spectrum, emission line spectrum, and absorption line spectrum as the speed changes. This change is called the Doppler effect, and is essential for measuring the speeds of objects located at a distance.
3. Suppose you were given a spectrum of a planet. The spectrum has a collection of absorption lines. Describe how you would use this simulation to identify what lines were present (or absent) in the spectrum, and therefore what atoms were present (or absent) on the planet.
Grading: all questions are weighted equally. Total points = [30].
Do not need a title page

Categories
Astronomy

Learning Goal: I’m working on a astronomy discussion question and need an explan

Learning Goal: I’m working on a astronomy discussion question and need an explanation and answer to help me learn.

Categories
Astronomy

Learning Goal: I’m working on a astronomy discussion question and need an explan

Learning Goal: I’m working on a astronomy discussion question and need an explanation and answer to help me learn.
Attention, Navigators, this is your Captain speaking,
It’s time to do something with your sextants. We are calling the inclinometer a sextant, now. The building of the sextant was worth ten points. Using it to determine the elevation of the Sun at local noon will also be worth ten points. The elevation of the Sun is the angle between the horizon and the Sun.
You will make observations of the Sun over a period of about four hours, from 10 a.m. to 2 pm., on a sunny day.
Sight along the straight edge of your sextant. Aim the straight edge at the Sun, just as you would aim the barrel of a gun. The weighted string will hang against one of the degree markings on the protractor. If you have an assistant, instruct him/her/it to take note of the degree mark the string hangs against. If no partner, try to press the string against the protractor as soon as you have sighted in the Sun, keeping the string in place, before you lower the sextant. Do this as fast as you can. Do not stare at the Sun for more than a few seconds. Wear sunglasses if possible.
Record the degree number under the string. If the degree number is less than 90, subtract the degree number from 90. For example, if you recorded 70, 90 – 70 equals 20 degrees. Record the 20 degrees. That angle is the elevation angle of the Sun. If the degree number under the string is greater than 90, subtract 90 from the degree number. For example, if you recorded 120, 120 – 90 equals 30. Record the 30 degrees. That angle is the elevation of the Sun. If you are simply writing down numbers that you see under the string and nothing more, YOU ARE DOING IT WRONG. Those numbers are not the Sun’s elevation. You must find the difference between the number under the string and 90, as explained above. THAT is the Sun’s elevation. The Sun’s elevation reaches a maximum around local noon. So, take an elevation measurement at 10 a.m., one at 10:30, 11:00, etc., every half hour until 2 pm. You will see the elevation numbers rise to a max, then decrease again. That max occurs around local noon.
Your measured elevations should fall in the range of 40 degrees to 70 degrees. I’m going to measure it too, so don’t just make stuff up. Submit a table of times and elevations. You must have credit for your inclinometer/sextant (previous project) to be eligible for points on this project.

Categories
Astronomy

Learning Goal: I’m working on a astronomy discussion question and need an explan

Learning Goal: I’m working on a astronomy discussion question and need an explanation and answer to help me learn.