BROOKINGS – On Wednesday morning, early risers will be treated to a lunar eclipse as the moon passes through the Earth’s shadow.

Unlike a solar eclipse, where the disk of the sun is completely blocked, a full moon is visible during an entire lunar eclipse with only its brightness and color changing. 

For those in the Brookings area, the moon will first enter the lighter part of the Earth’s shadow, called the penumbra, at 4:51 a.m. This is a subtle effect and will be seen as a dimming of the moon’s reflected sunlight. As the eclipse progresses, the moon will appear much darker and take on a reddish hue when it passes into the darker, umbral shadow.  

The coppery, red hue often observed during totality is due to the scattering and refraction of sunlight through Earth’s atmosphere. Short wavelengths of light from the sun, such as blue light, are scattered by dust particles and bend more as they pass through the Earth’s atmosphere, leaving red as the dominant wavelength of visible light in the umbral shadow. For this reason, a lunar eclipse is sometimes referred to as a blood moon or a blood red moon.

The moon will enter this darker part of Earth’s shadow at 5:48 a.m. and reach totality at 6:51 a.m. The maximum eclipse, where the moon is in the center of Earth’s shadow, will occur at 7:29 a.m. 

Fortunately, this will occur before the moon sets or the sun rises for those in the Brookings area. Viewing the eclipse requires no special equipment, just an unobstructed view of the western-northwestern sky. 

While the eclipse begins with the moon about 30 degrees above the horizon, totality will not occur until the moon is less than 10 degrees above horizon. The moon will set in Brookings before the eclipse ends. In the event of cloudy skies, check www.NASA.gov for a live feed of the event.

Like solar eclipses, lunar eclipses are somewhat rare, only occurring only two to three times per year. 

Although the moon orbits the Earth approximately once per month, its orbit is tilted about five degrees from the Earth’s orbital plane, resulting in the moon passing above or below the Earth’s umbral shadow much of the time.

The Jan. 31 lunar eclipse is being referred to as a Super Blood Blue Moon. It is a super moon because the moon is a bit closer in its elliptical orbit during its full moon phase, making it appear slightly larger and brighter than average. It is a blue moon because it is the second full moon occurring in a single month. 

Associated Press photo: In this Aug. 28, 2007, file photo, the moon takes on different orange tones during a lunar eclipse seen from Mexico City. During a lunar eclipse, the moon’s disk can take on a colorful appearance from bright orange to blood red to dark brown and, rarely, very dark gray. On Wednesday, a super moon, blue moon and a lunar eclipse will coincide for the first time since 1982 and will not occur again until 2037.