dipper@utastro.UUCP (Debbie Byrd) (11/28/85)
The first surface feature on the red planet Mars was seen on today's date in the year 1659. More on Syrtis Major -- in just a minute. November 28 A Dark Triangle on Mars On today's date in the year 1659, an astronomer named Christiaan Huygens was peering through his telescope at the planet Mars. He noticed a dark marking on the disk of that world -- the first surface marking on Mars ever seen from Earth. The first known surface feature on Mars is now called Syrtis Major. It looked to Huygens like a large dark triangle on the red planet. Huygens used Syrtis Major to notice an interesting fact. Every night, as he peered through his telescope, Syrtis Major seemed to be in about the same position as it was the night before. He made a note in his diary that Mars appears to take about 24 hours to spin on its axis -- same as the Earth. And so it does. Interestingly enough, on today's date in the year 1964, a spacecraft was launched that got the first close-up pictures of the red planet. That craft was Mariner 4. It showed that Mars was heavily cratered and very dry -- in some ways more like the moon than the Earth. Later spacecraft photos let us take a good look at Syrtis Major itself. The oldest known feature on Mars -- a great dark triangle in the telescope of Christiaan Huygens -- is now known to be a large wind-streaked plain -- possibly a region scarred by ancient volcanos. What a thrill it'll be someday when people visit this alien terrain in person. Script by Deborah Byrd. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin