Astronomy and outer space have always fascinated me. 'On Friday, May 19, the year's only "black moon" will rise in the sky — and there will be precisely nothing to see'. An event like this only takes place around every 33 months. The term "black moon" does have other meanings, and is a term that describes other lunar events. But in this case, it refers to the third new moon in an astronomical season with four new moons.