Here’s Looking at You, Mars!

Abstract

Techniques are developed to observe Mars as it moves against the starry background. This is done by piggybacking a digital single-lens reflex camera onto a telescope driven by an equatorial mount. The telescope itself is used to guide the mount by tracking individual stars and correcting the tracking of the mount. At first, the tracked object was the planet being studied. As the author’s equipment improved, the guiding was done by tracking a star. This proved to be more accurate. The resulting photographs were imported into a computer-aided-drafting (CAD) system, where measurements could be made by freehand drawing around the stars and planet and then using the “snap” tools in the CAD system. A Fortran program to obtain right ascensions and declinations of Mars at the observation times is given. The results are summarized for observations of three apparitions of Mars.