The total lunar eclipse expected Wednesday morning will offer a rare sight for some viewers.
The total eclipse and the rising sun will be in the sky simultaneously for a short period of time, allowing watchers to to catch a glimpse of both.
This rare phenomenon is known as a selenelion-- an effect that celestial geometry says can't happen, according to CBS News.
Most often, a lunar eclipse occurs before sunrise. On Wednesday morning, the Earth, while passing between the moon and sun, will eclipse the moon in the process.
This will last through sunrise.
The moon and sun are often visible in the sky at the same time- so what makes this occurrence special?
During a lunar eclipse, the sun and moon are 180 degrees apart in Earth's sky- with one rising as one sets- which should make it theoretically impossible to see both.
Thanks to a trick of the light, in which the atmosphere bends light at a certain angle near the horizon, an optical illusion will make the sun and moon appear slightly higher in the sky.
According to Business Insider, observers in Australia, western Asia, islands in the Pacific Ocean and some of North America will have the chance to observe this eclipse.
What should skywatchers do for a chance to catch a glimpse? Be outside slightly before sunrise, with a clear view of the east and west horizons.
