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If you鈥檙e up early tomorrow morning and the skies are clear, there is a special sight in the sky for you.

By themselves, a lunar eclipse, a supermoon and a blue moon aren鈥檛 that uncommon. But it鈥檚 rare for all three to happen at the same time, like they will tomorrow when the lunar eclipse starts at about 2 a.m.

Lunar eclipses happen, on average, about every six months somewhere on Earth according to Sally Kilburg, South Okanagan vice-president for the Okanagan chapter of the Royal Astronomical Society of Canada.

A blue moon, the second full moon in a month, isn鈥檛 quite as common, but is still a regular occurrence, as is a supermoon, marking the point when the moon is closest to Earth in its elliptical orbit.

Having all three happening together is anything but regular.

鈥淚 don鈥檛 know of another instance. I would have to go digging through astronomical information to see if there is anything else out there,鈥� said Ken Tapping, an astronomer with the Dominion Radio Astrophysical Observatory near Penticton.

While the moon may look a bit larger because of its closeness to the earth, the most dramatic change will be its colour, shifting to red and orange hues, which give rise to the 鈥渂lood moon鈥� nickname for a lunar eclipse.

With the earth blocking the light falling on the moon, you might expect it to vanish into the darkness. Tapping explains the moon is being lit by light refracted by the Earth鈥檚 atmosphere acting like a lens, bending sunlight and lighting the moon.

鈥淏ut of course this light is going through thousands of kilometres of the Earth鈥檚 atmosphere,鈥� said Tapping. Like a sunset, only the longer red and orange wavelengths are making it through the atmosphere to fall on the moon.

鈥淚t鈥檚 a beautiful thing, the moon turns different colours. To my eye the moon looks more like a sphere in a lunar eclipse,鈥� said Kilburg, adding that unlike the solar eclipse last summer, lunar eclipses can be observed from a wide area.

鈥淎 lunar eclipse is something that is quite broad, it鈥檚 the shadow of the Earth falling on the moon,鈥� said Kilburg. 鈥淲e are looking at our own shadow 鈥� it鈥檚 a pretty big shadow compared to the moon.鈥�

Tapping said one of the things that would have struck us very early on in human history was the regularity of the objects in the sky, creating the awe and fascination that continues to the present.

鈥淭he sun rises every day and the moon goes through its phases and even back thousands of years B.C., people could predict eclipses of the sun,鈥� said Tapping. 鈥淗ere on earth, everything was very uncertain. Sometimes the rain came, sometimes it didn鈥檛. You couldn鈥檛 predict when thousands of men with sharp sticks were going to appear over the crest of a hill.

鈥淵et in the sky, the rhythm, unchanging, perfect all the time. I think this is the beginning of people seeing perfection in the heavens, compared with the Earth. So what went on in the heavens became important.鈥�

Tapping said that history is one of the things he loves about astronomy.

鈥淵ou look at the sky, you see the constellations, the memories of our mythology,鈥� said Tapping. 鈥淎 lot of the stars have Arabic names, some have Latin names, some have more modern names 鈥� we have been writing our culture and history in the sky for thousands of years.鈥�

For those wanting to observe this special event, the moon starts to move into the Earth鈥檚 outer shadow at 2:51 a.m. on Jan. 31, which is when Tapping said you will first notice some darkening. Then at 3:48 a.m., you will see the real shadow of the earth start to cross the moon and by 4:51 a.m., the moon will be completely covered. By 6:07 a.m you will see the Earth鈥檚 shadow start to move off the moon and at 7:11, that will be over.

鈥淭his is a relatively long total lunar eclipse, with totality lasting for 1 hour, 16 minutes,鈥� said Kilburg. 鈥淭he entire event from the first hint of our penumbral shadow on the face of the moon till the last whisp of penumbra is about 5 hours, 17 minutes.鈥�

For those who can鈥檛 see the eclipse due to cloud cover, you鈥檒l still be able to watch online. NASA, the U.S. space agency, will be broadcasting live coverage on their .