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Mars (July, 2017) ⬅︎
Mars is a tantalizing planet. At its best, it can appear bright orange-red, with a surface that reveals gigantic volcanoes and canyons, and ice caps made of cold carbon dioxide that change in size. It even has two small moons, Phobos and Deimos, that may be glimpsed. However, much of the time, Mars appears as a pale, featureless orb.

The key to understanding this is distance. At its closest, Mars may be fairly close at just 35 million miles away. At its furthest, it may be 250 million miles away, or 7 times further. How can this be?

It is easy to understand Mars' changing distance from Earth if you think of Earth and Mars as runners on a circular track with the Sun at the center. Earth is in the inside lane. They start off side-by-side, but Earth is faster and pulls ahead quickly. In time though, since the track is circular, Earth catches up to and laps Mars getting very close once again. This cycle takes 26 months.

The time when Earth is alongside and close to Mars is known as an opposition. Stargazers with telescopes eagerly await each opposition in hopes of seeing Mars at its best. But what can be seen really depends on the weather on both Earth and Mars. On Earth, if the 'seeing' is not good (too much twinkling), details will be fuzzy or lost. On Mars, if there are global dust storms, there won't be anything to see.

Viewing the best of Mars requires lots of patience and luck. Yes, Mars is a tantalizing planet.
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WARNING
Never use binoculars or telescopes to view near the sun.