Learning Curve 2 - Motion
Download FTS images for this lesson here.
Here are several images of the Belt of Orion (the three bright stars)
times listed are in 24 hour time (hour:minute:second) so 20 means 800 PM. Times are start of exposures.

The camera was not moved between nor during the exposures.

All images taken with cradle camera, approx. 8 degree FOV. There was considerable light at this site in Eugene, in back of the Planetarium. The skyglow and local lights show up in some of the images, particularly the 100 second exposure. There were also high clouds coming in.

The 100 second exposure was taken to show the "drift" of the stars, and can be used for calibrating the field of view and the plate scale.

The belt stars are difficult to pick out in the lamp glow.

SBIG claims that exposure times should be accurate to .01 second timing.

Inquiry Claim example: Stars are moving in space.

Activity: Measure the angle of change per unit of time. How far would
you expect a star to appear to move in an hour? (how much of an angle?)

What do you notice about the group of 3 belt stars as time goes by?
(Look at other patterns of stars as a night progresses.)

Is there another explanation for the apparent motion of the stars?







Image Belt 1 taken at 20:05:01 2-7-01 3 second exposure
Image Belt 2 taken at 20:06:50 2-7-01 3 second exposure
Image Belt 3 taken at 20:08:08 2-7-01 3 second exposure
Image Belt 4 taken at 20:09:21 2-7-01 3 second exposure
Image Belt 100 taken at 20:13:02 2-7-01 100 second exposure