Mars at Opposition

This Tuesday night, Mars is at opposition. What does that mean? In practical terms, it means it is the best time to view Mars; it is at its brightest and it is visible in the sky all night long (from sunset to sunrise the next morning). In astronomical terms, it means that Earth is directly between Mars and the Sun. Earth orbits closer to the Sun than Mars does, so Earth moves faster in its (smaller) orbit. Opposition is the time that Earth catches up and overtakes Mars–like a runner on the inside lane of a track passing a slower runner on an outside lane.

Universe Today has a more thorough description of Mars at opposition, and the article explains why some oppositions are better than others. While Earth’s orbit is nearly a perfect circle, Mars’s orbit is not, and so the distance between Earth and Mars at closest approach (opposition) varies considerably.

Look for Mars as soon as it gets dark. It will be in the eastern sky, rising higher as the night progresses. It is not hard to spot; Mars is the bright orange light near the bright white star Spica.