Update: 6:37PM WHETHER you think its portentous or pretty, the moon will be pulling focus this week, blushing blood red as it falls into Earth's shadow.
The moons orangey-red appearance this week is due to a syzygy or a perfect alignment of three celestial bodies of the sun, the Earth and the moon.
National Geographic explains that the moon's red colouring is due to sunlight passing through the Earth's atmosphere and refracting to the red end of the spectrum.
Lunar eclipses do not happen every month, because of the moon's tilted orbit around us. Their frequency varies widely: from one every few years to five in a year.
Tuesday night's eclipse will be the first in a tetrad, or series of four. Subsequent eclipses will occur on October 8 this year and April 8 and September 28 next year.
The shade of red that the moon turns cannot be forecast, and is largely dependent on the amount of dust circulating in Earth's atmosphere at the time of the eclipse.
The best time to see this week's blood moon as it is called is on Tuesday night.
Unlike solar eclipses, the lunar eclipse/blood moon phenomenon is perfectly safe to view and to photograph.