Around 10:11 EST tonight — on the eve of September 27, 2015 — there will be a Super Blood Moon.
What, you may be asking, is a Super Blood Moon?
Per NASA, who would know, a super blood moon is a rare cosmic event in which a supermoon coincides with a lunar eclipse. There has not been a super blood moon since 1982, and there likely will not be another until 2033.
As a result, the moon will appear larger, and significantly brighter, than normal, and will take on a coppery-red tone — hence the name "blood moon."
Is it going to kill us?
Well, yes. At least, according to some people, who argue that this supermoon is the last of four in a "tetrad," or the name for a six-month period in which four blood moons occur, and which some Christian preachers say is in line with end-of-world prophecy found in The Bible.
However, not everyone is certain the end is really all that nigh.
Noah Petro, deputy project scientist for the Lunar Reconnaissance Orbiter with NASA in Maryland, says that we will probably be OK: "The only thing that will happen on Earth during an eclipse is that people will wake up the next morning with neck pain because they spent the night looking up."
Still, should we get very worried, just in case?
Also, if you are reading this post after September 27, I guess everything is fine and you can just forget this whole thing.