A supermoon has lit up the sky across the world, coinciding with a rare partial lunar eclipse. That meant the Moon - which is at its closest point to Earth in its orbit - appeared brighter and bigger on Tuesday night. See more supermoon sightings from around the world here.

If you look up in the Kansas and Missouri skies on Tuesday, Sept. 17, you may be able to catch a glimpse at not only a supermoon—but also a partial lunar eclipse.

If you happened to notice the supermoon looking especially large as it was rising, you may have fallen victim to a “well-known, poorly studied optical illusion,” said NASA’s Noah Petro. Here’s the scientific explanation of what you were seeing,