On November 19, 2021 (late evening of the 18th in some time zones), the Moon passes into the shadow of the Earth, creating a partial lunar eclipse so deep that it can reasonably be called almost total.

I love all phases of the moon but a full moon is particularly beautiful, don’t you agree?

A lunar eclipse occurs when the Sun, Earth, and Moon align so that the Moon passes into Earth’s shadow. In a total lunar eclipse, the entire Moon falls within the darkest part of Earth’s shadow, called the umbra. In this eclipse, up to 99.1% of the Moon’s disk will be within Earth’s umbra.

During the eclipse, the Moon moves through the western part of the constellation Taurus, my own sign, so I’m excited about that!

The same phenomenon that makes our sky blue and our sunsets red causes the Moon to turn red during a lunar eclipse. It’s called Rayleigh scattering.

Light travels in waves, and different colors of light have different physical properties. Blue light has a shorter wavelength and is scattered more easily by particles in Earth’s atmosphere than red light, which has a longer wavelength. Red light, on the other hand, travels more directly through the atmosphere.

When the Sun is overhead, we see blue light throughout the sky. But when the Sun is setting, sunlight must pass through more atmosphere and travel farther before reaching our eyes. The blue light from the Sun scatters away, and longer-wavelength red, orange, and yellow light passes through.

I hope for a clear sky tonight. In Southern California, the eclipse will begin at 10:02 p.m. on Thursday and will last for a little over six hours, the longest one since the 1400s.

Info curated from SciTechDaily