Scheduled air date: 2001 May 07-13
Click here to view a QuickTime Movie presentation of Mars' retrograde motion (992KB)
As we pass by the planet Mars, it will get brighter and its motion against the starry background will appear to slow down. At the end of this week, Mars will appear to have stopped, and will then slowly begin moving backward during what astronomers call retrograde motion. In the third week of July, Mars will again appear to have stopped, after which it will resume its usual forward motion.
(Mars' position this week is shown above about an hour before sunrise for mid-Northern latitudes.)
This year June 21st will not only mark Summer Solstice—the beginning of Summer for Earth's Northern Hemisphere—but will also be when Mars is at its closest to Earth in 13 years! At this time the two planets will be a mere 67 million kilometres / 42 million miles apart.
(The four inner planets of our Solar System are shown in their orbits from above the Sun's north pole over a six-month period.)
If you wish to view illustrations for other episodes, please see our Star Gazer Illustrated directory.
|Illustrations on this page were created using
Software, an advanced desktop planetarium program designed for Windows.|
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