(FOX NEWS) - Millions of people across the world will witness a partially red-tinted night sky as a rare celestial event arrives this weekend: a "super wolf blood Moon" eclipse.
North America hasn't had a decent view of this special scene in at least three years and another total lunar eclipse -- which occurs when the entire Moon enters Earth's shadow -- isn't expected to happen again until 2021, NASA predicts.
"There is a little less than one total lunar eclipse per year on average. A lunar eclipse can only happen during a full moon when the Moon is on the opposite side of the Earth from the Sun," Walter Freeman, an assistant teaching professor in the Physics Department at Syracuse University, said in an emailed statement to Fox News. "But the Moon's orbit is tilted a little bit compared to the Earth's, so usually when the Moon is full, the Earth's shadow passes a little bit above or a little bit below it. This is why we don't have a lunar eclipse every month."
The 2019 total lunar eclipse will last approximately 1 hour and 2 minutes, Space.com reports. It will kick off around 11:41 p.m. ET on Jan. 20 and peak around 12:16 a.m. ET on Jan. 21.
"The Moon won't be completely invisible during the period of totality when the Earth's shadow completely covers it! A little bit of sunlight is refracted by the Earth's atmosphere and reaches the Moon, bending around the edges of the Earth. This small amount of red light still illuminates the Moon enough for us to see it. Instead of being bright and white, the Moon will be very dim and red, ten thousand or so times dimmer than usual; people call this a 'blood Moon,'" Freeman explained.