The lunar eclipse scheduled to take place on April 14-15th promises to give sky watchers an unusual and even rare event.
Lunar eclipses usually happen at random - you can get a total eclipse, followed by a prenumbra, then a partial and then another total - but this time - there will be four total eclipses in a row... known as a tetrad. All of them will be visible from North America. Tonight and tomorrow night is the start of this tetrad - with the others following on October 8, 2014, April 4th and September 28, 2015.
Although tetrads are somewhat rare, with the exception of eight that will occur this century, this one is rare because it is the first tetrad sequence to happen while the Earth, Mars, and the Moon are aligned.
A normal lunar eclipse occurs when the sun, moon, and Earth align so that Earth’s shadow falls across the moon's surface. Monday night's lunar eclipse is a total eclipse, which means Earth's shadow will cover the moon completely.
The moon won't be blacked out by our planet's shadow. Instead, it will take on a reddish hue -- anywhere from a bright copper to the brownish red of dried blood.
Perhaps this is why we are seeing the term "blood moon" popping up all over the news.
North America, as well as Central America and parts of South America, will have a front row seat to this rare event. If you live on the West Coast, you are especially lucky because you won't even have to stay up too late to see it.
The event is expected to begin at 10:20 pm PST, where a faint shadow will begin to fall on the moon. This is known as a penumbral eclipse, which is pretty subtle.
But keep watching, because at 10:58 p.m., the partial eclipse begins and a section of the moon will appear to be missing. And later, the Earth's shadow will move across the moon, covering more and more of its surface minute-by-minute.
"If you were standing on the moon during a total lunar eclipse you would see the Earth as a black disk with a brilliant orange ring around it," said Alan MacRobert, of Sky and Telescope magazine. "And this brilliant ring would be bright enough to dimly light up the lunar landscape."
By 12:07 am, the complete lunar surface will be in Earth's shadow. It will be glowing red, because even though our planet is blocking out direct sunlight, the light from the sun will still make it to the lunar surface, from behind Earth. The planetary show is expected to last until around 1:25 am, PT.
The unique term, "blood moon" that might sound a bit foreign, indeed is, as MacRobert has been writing about astronomy since 1982, and had never encountered it before.
According to Hagee's ministry website, the book "explores the supernatural connection of certain celestial events to biblical prophecy."
Either way, call it a red moon or blood moon, it will be something worth staying up late to observe.
"I really urge everyone to watch the progress of this eclipse," MacRobert said. "Whether you have a small telescope, a pair of binoculars or even just your naked eye -- you'll be seeing part of the geometry of the cosmos happening right in front of your eyes."
Image via NASA