October is set to get a little spookier this week when the second and final lunar eclipse of the year offers night sky aficionados a glimpse of the red-tinged "blood moon."
According to NASA, the total lunar eclipse officially begins at 6:25 am eastern time on Wednesday, October 8. Weather permitting, those west of the Mississippi will have the best view, since the moon will set too early across much of the eastern United States.
Total lunar eclipses occur when he Earth passes directly between the sun and the moon, putting the moon squarely in the Earth's shadow, or umbra. Sunlight reflected from our planet's surface onto the moon will give the lunar disc a reddish cast. The blood moon was seen earlier this year on April 15 and will reappear on April 4, 2015 and September 28, 2015 as part of an infrequent 'tetrad' eclipse sequence.
Read more: San Francisco Chronicle