Perhaps you’ve already noticed the dazzling red dot dancing in the night sky. That’s Mars, our planetary neighbor. And for the past few weeks it has been growing brighter as it slowly approached a state that astronomers call opposition, when it and the sun are on opposite sides of Earth. It’s like we’re in between the two right now in a cosmic game of monkey in the middle.

This occurred on Friday. It is now being followed by Mars’s closest approach to Earth Monday into Tuesday, and everyone in the world can watch, weather permitting.

How often does Mars opposition occur?

Earth and Mars align with the sun in opposition about once every two years.

But truly jaw-dropping midnight views of Mars happen every 15 to 17 years. That’s when opposition occurs when Mars is at perihelion, or its closest position to the sun, according to Rich Zurek, project scientist for NASA’s Mars Reconnaissance Orbiter. This upcoming opposition will be one of those moments.