Comet Watch PREFLIGHT
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The following questions refer to the material you were to read in preparation for the lesson.

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The Sun

This java applet lets you explore the sun using different frequencies of light: white (visible) light, x-ray, h-alpha, and extreme ultraviolet. You can also explore a magnetogram, which shows you the direction of the magnetic fields near the solar surface.

The full disk image of the sun that you can see on the right is a white-light, or visible light image. Click on the buttons below it to select one of the filters, then drag the filter box around the sun to examine different parts of the solar disk.

You must use version 4.06 or later of Netscape Navigator or version 4.0 or later Internet Explorer to view this applet.

About the filters

A schematic view of the sun show the different layers of the solar atmosphere.
Different frequencies of light are formed in different parts of the solar atmosphere. As a result, by looking carefully at only a particular frequency of light we can look at different layers of the sun's atmosphere. The visible layer of the sun's atmosphere is called the photosphere. Above that is the chromosphere, and above that is the solar corona, which at 1 million degrees F is the hottest part of the solar atmosphere.

White light

The full spectrum of visible light. This shows the photosphere, and is the image you see if you view the sun using a pinhole camera.

H-alpha

H-alpha images are taken through a filter centered on a particular frequency of visible red light -- one of the spectral lines of Hydrogen. This light forms in the chromosphere, above the visible photosphere but below the corona.

Extreme Ultraviolet

This frequency of light is also formed in the chromosphere. The particular frequency used here forms high in the chromosphere and in the lower regions of the sun's corona.

X-ray

The X-rays we can see form in the outermost layer of the sun's atmosphere, the solar corona.

Magnetogram

Certain frequencies of light are sensitive to the presence of magnetic fields. If we take a picture of the sun using those frequencies we can calculate the direction and intensity of the magnetic field near the solar surface. In the image used here the colors red and blue are used to indicate magnetic fields pointing toward and away from the solar surface.

Question: What is the correct ordering of the filters from closest to the sun to farthest from the sun? As you follow a structure through the layers, how does it change?




honors extra

The filters show two things at once, they show higher layers of the atmosphere and higher temperatures of the gas (or plasma). If you notice the X-ray image is a higher layer of the atmosphere, and X-rays show million degree temperatures, how is it that the sun gets HOTTER as you look at higher levels? Most things cool off as they leave the source of heat, but the sun's atmosphere heats up. Why?




Below is a space for your thoughts, including general comments about today's assignment (what seemed impossible, what reading didn't make sense, what we should spend class time on, what was "cool", etc. ):




You may change your mind as often as you wish. When you are satisfied with your responses, click the SUBMIT button.

I received no help from anyone on this assignment.