A supermoon occurs when the full moon is at its perigee, the point in its orbit where it is closest to Earth. This makes the moon appear up to 14% larger and 30% brighter than when it is at its farthest point, or apogee. While visually impressive, it is a normal astronomical event.
What Is a Supermoon?
A "supermoon" is a popular term for when a full moon coincides with the Moon's closest approach to Earth in its orbit, making it appear slightly larger and brighter than usual.
Quick Answer
A supermoon happens when a full moon occurs at the same time the moon is closest to Earth in its orbit. Because it's closer, it can look about 14% bigger and 30% brighter than a normal full moon.
Related Questions
What is UTC (Coordinated Universal Time)?
UTC is the primary time standard by which the world regulates clocks. It's the successor to GMT and is based on atomic time for precision.
What is Daylight Saving Time (DST)?
DST is the practice of advancing clocks by one hour during warmer months to extend daylight into the evening.
What does GMT stand for?
GMT stands for Greenwich Mean Time, the historic time standard based on the Prime Meridian in Greenwich, London.
What are leap seconds?
A leap second is a one-second adjustment added to UTC to keep it in sync with the Earth's irregular rotation.