SIZES AND DISTANCES
IN THE SUN-EARTH-MOON SYSTEM:
An Introductory Astronomy Lab
Rung 2: The distance to the Moon
In the following you will be using a real video images of a lunar eclipse
which took place on September 16, 1996. You will derive the relative sizes of
the Moon and Earth by using the time stamps in the image to determine how long
it takes the Moon to pass through the Earth's shadow. The time you are
concerned about is the time that the limb of the Moon just enters the umbra
(the darkest part of Earth's shadow) to the time that it just shows up again
as a bright crescent.
- Record the time at which the Moon just starts
the umbra. The inset images that appear halfway through the movie are images
of the Moon during totality, right after this we see the Moon reappear as a
thin bright crescent, record the time at which this happens.
- To view the movie
again click on the RELOAD button (you may need to do this several times
since the movie goes pretty fast).