Techniques of Observational Astronomy
AST3722C

The Sun and Geosynchronous Satellites

A former student of mine sent the follow e-mail and image. Can you figure out the answer to his puzzle? Note: He is asking about angles, not time, so this is not the same as the earlier homework question. Hint: just where are geosynchrounous satellites located (in three dimensions).

I took this photo across College Blvd from WSRE at 12:38 PM CDT on October 8, 2002. Note the Sun is directly above the focal point of the cassegrain radio antenna (see how all 4 struts are exactly centered on the disk). As the geosynchronous satellite this dish is focused on is supposedly in orbit directly over the earth's equator, why wasn't the Sun directly behind the satellite two weeks ago? Any ideas?

This page was last edited October 8, 2002 3:35 PM