On September 27, sky spectators in North America, South America, the Atlantic Ocean, Greenland, Europe, Africa, and the Middle East will be able to see the moon at its closest point to Earth (known as its perigee). The moon reaches its perigee (and the apogee, which is its furthest point from Earth) about once a month. However, it does not always reach that point when it's full. This week, we're in luck. The full moon will appear about 14 percent larger in diameter than usual, and is thus called a super moon. At the same time, the Earth will pass between the sun and the moon, creating a total lunar eclipse.
To make it even more exciting (or scary, depending on how you look at it), it's also what is know as a Blood Moon. It's the fourth full lunar eclipse in a row (a.k.a. a tetrad), with no partial eclipses in between.
According to a fun investigation by EarthSky.org, the menacing "blood moon" moniker comes from biblical prophecy. It also pretty accurately describes the color of the moon during the eclipse. The moon appears red during a total lunar eclipse mostly because of the Earth's atmosphere. When the Earth passes directly between the sun and the moon, our home planet casts its shadow over the moon. If the Earth had no atmosphere, the moon would be dark, and basically invisible to the non-existent humans who would definitely not survive without the atmosphere.
The last time a super moon eclipse took place was 1982, and if you miss this one, there won't be another until 2033. NASA has a nice detailed set of videos to show when the magic happens in different time zones, so be sure to find your area and get your eyes on the sky.