Photo: An artist’s rendition of Mars in proximity to Earth | Getty Images
Mars is reaching full opposition on October 13, 2020, when it will be biggest and brightest in our skies. Mars oppositions occur approximately every 2 years, but this year one special—Mars won’t appear to be this big and bright again for another 15 years.
What is the Opposition of Mars?
Opposition occurs when a planet is on the opposite side of the celestial sphere to the Sun, as observed from Earth. During opposition, the planet in question is at its closest point to Earth in its orbit and in its full phase. This makes the planet appear bigger and brighter in the night sky than usual, creating ideal conditions for observation.
When Mars reaches opposition, Earth is directly between it and the Sun | Kel Elkins/ NASA
What makes this opposition special?
It takes 687 days, for Mars to complete a trip around the Sun—the time it takes for Earth to complete 2 orbits. It is for this reason that Mars and Earth only line up every two years. Because the two planets follow elliptical paths in their orbits, some oppositions occur at closer points than others. ...