Opposition of Mars at its Closest
Mars comes closest to Earth roughly every 15 to 17 years, with the last one in 2020. According to NASA, the “opposition occurs within a few weeks of Mars’ perihelion (the point in its orbit when it is closest to the sun). An opposition can occur anywhere along Mars’ orbit. When it happens while the red planet is closest to the sun (called “perihelic opposition”), Mars is particularly close to Earth.”
If you missed the last one, make sure you try and catch the next one. Back in 2003, the opposition was the closest approach in almost 60,000 years, and is something that will never happen in our lifetime again (Mars).