I hope your sky was clear for the total lunar eclipse. It sure wasn’t here. A big bank of clouds moved in before totality. I was shocked when I looked at the window to see a clear sky in the east and not a single star – or moon – in the west. That’s why man invented the car.
25 miles north of town the burnt orange moon slid out from under the clouds. It was already mid-eclipse, but no matter. I pulled over to the side of the road to enjoy the sight as twilight crept up from behind.
In binoculars Uranus was plain to see near the lower edge of the moon where the color was deep, rich and red. Up along the lunar topside the color graded to a pale straw yellow.
Clouds threatened again sending me fleeing to a lake shore and finally another roadside. Around 6:30 a.m. traffic picked up. Everyone driving south or west on their way to work and school got the astronomical treat of their life – the moon emerging from total eclipse right out the front windshield. Sweet!
For a total lunar eclipse to happen, the moon must be full and lie in the same plane as Earth’s orbit. Since the moon’s orbit is tilted 5°, it normally misses Earth’s shadow at full, passing a few degrees above or below it.
The full moon orbits behind the Earth opposite the sun; as the sun rises the moon sets. At the moon’s distance of 240,000 miles, the Earth’s shadow, both penumbra and umbra, spans a little more than 2° or about the size of the Pleiades star cluster.
Seems pretty small, doesn’t it?
But viewed from the ground, Earth’s shadow reaches from one end of the western horizon to the other. In the evening, the shadow is equally broad but appears in the eastern sky. This morning we had the unique opportunity to see the partially eclipsed moon in Earth’s distant shadow at the same time as seeing the much bigger near-shadow of the planet. Wild thought.