Total Lunar Eclipse Tonight — And Weather Forecast’s Hopeful
If the clouds cooperate – and the National Weather Service is serving up some hope here — a total lunar eclipse will be visible tonight from the Big Island.
In Hawaii, the eclipse will begin at 7:58 p.m. and end at 11:33 p.m., with totality between 9:06 p.m. and 10:24 p.m., the Bishop Museum’s J. Watamull Planetarium said.
Full moon in Hawaii is at 9:43 p.m.
The National Weather Service is calling for partly cloudy conditions tonight over windward areas with haze and isolated showers over leeward sections.
Lunar eclipses occur when the Earth passes between the sun and moon, and the moon enters the Earth’s shadow.
Since this will be a total eclipse, the shadow will gradually encroach upon the moon until it completely covers it. At that point the moon often appears red, because our atmosphere, which extends about 50 miles above the Earth’s surface, filters out some of the sun’s spectrum of light.
In essence, the green to violet portion of the spectrum is removed, while the reddish portion is least affected.
The reddish light is also bent or refracted toward the Earth as it passes through our atmosphere, which pushes it onto the moon’s surface.
According to EarthSky.org, the degree of redness depends on atmospheric conditions including dust, humidity and temperature, giving it a hue that ranges from copper-colored to deep red.
Dust sent into the atmosphere from the 1991-92 eruption of Mount Pinatubo in the Philippines made the December 1992 lunar eclipse difficult to see, EarthSky.org said.
Another lunar eclipse will be visible from Hawaii in October.