The end is nigh, Engadget readers: a triumvirate of celestial events is happening simultaneously. Okay, that might be a bit of an overstatement, but until we hit the other side of today's supermoon, spring equinox (yay!) and total solar eclipse, we just won't know. As The Wall Street Journal tells it, this sort of thing is "extremely unusual." Total solar eclipses -- where the moon plays middleman and blocks the sun from our view -- happen about once every year-and-a-half. Supermoons and the equinox? A handful of times per year and once annually, respectively.