Supermoon and 'Blue Moon' – Rare Sightings in the Sky

Especially bright and large: It was possible to admire the supermoon in the sky last night. According to NASA, this happens when Earth's companion is particularly close to our planet in its elliptical orbit and there is also a full moon. The full moon then appears especially large and bright due to the smaller distance in the sky, and if the moon is in a position close to Earth, it can appear up to 14 percent larger than when it is farthest from Earth, NASA writes. Last night the moon was about 360,000 kilometers away, and by the time of the next full moon in mid-September it will be only about 357,000 kilometers away.

Did the moon shine blue?

According to NASA, the moon wasn’t just a supermoon, it was also a seasonal “blue moon.” Does that mean the moon had a bluish glow? “No,” NASA says. “This is simply the name for two full moons in a month or the third full moon in a season of four full moons.” There are usually three full moons in a three-month season. But if there is a fourth full moon, it will be a seasonal “blue moon.” According to NASA, only about six percent of all full moons are seasonal or monthly “blue moons.” Because of the rarity of this event, the English phrase “once in a blue moon” means “once in a jubilee.”