Eclipses

Charting the Planets,
the Sun and Eclipses

"The Diamond Ring"
Solar Eclipse

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Mr. R.

REQUIREMENT #3: Do ONE of the following:

(a) In a sketch show the position of Venus, Mars, or Jupiter in the sky at approximately weekly intervals at the same time for at least four weeks.

"The Sky" by Software Bisque

* At Sky & Telescopes home page click on observing>, then sky chart, then view sky chart. You may be asked to register, which is FREE. The site is well worth searching.

Find out which planets will be visible during the next month. These may be found in Astronomy magazines or on the Internet. Sky & Telescope* has an excellent site.

If a planet is visible, go out at night and find it according to the charts. On an 8x10 sheet of paper, draw some familiar land marks or constellations. Now show where your planet was located. Repeat this for a number of weeks.

-OR-

(b) Using a compass, record the direction to the sun at sunset at approximately weekly intervals for at least four weeks in spring or fall (for six to eight weeks in summer or winter) and relate this information to the seasons of the Earth.

Hopefully, you'll notice the errors in the above example.

Go outside just before the sun sets. On an 8x10 sheet of paper, draw what the horizon looks like (just for reference).

Using a compass, measure the angle of the sun as it sets. Label the degrees you measure on your drawing (see example).

At weekly intervals, repeat the process. Remember, 6-8 weeks in the summer or winter).

-OR-

(c) With the aid of diagrams explain the relative positions of sun, Earth, and moon at the times of lunar and solar eclipses and at the times of New, First Quarter, Full, and Last Quarter phases of the moon.

Stand in the bright sun and look at the shadow your body casts. If you kneel down and take a closer look you will see that the edges of the shadow are a little softer or fuzzy and not as black as the middle of the shadow is. Similarly, when the Earth or the Moon cast shadows on each other, the edges are not as dark as the middle. The outer (softer) shadow is called the penumbra, while the inside (darker) shadow is called the umbra. During an eclipse, a body will start into the penumbra first, then and umbra, and finally exit through the penumbra again.

Lunar and Solar Eclipses You may print out this helpful handout containing both the lunar and solar eclipse drawings. Label the Sun, the Earth, the Moon, the Umbra and both of the Penumbras.

You'll need Adobe Acrobat^© Reader (free download) to print the above handout.

The Phases of the Moon shows the relationship of the Sun, Moon, and Earth as the Moon rotates around the earth.

This amazing photograph of the moon's shadow passing over the earth's surface during a solar eclipse was taken by the crew of the space station Mir 27. A larger photo along with an explanation by the photographer may be found at "Astronomy Picture of the Day."

Notice that as the moon progresses through the eclipse it turns gray when it enters the penumbra (partial eclipse), turns reddish orange as it passes into the umbra (total eclipse), turns gray as it starts to exit, and finally turns white again. Lunar eclipses only take place during a full moon.

To learn more: The Eclipse Zone