Total Lunar Eclipse Live Stream from the Observatory at the Springfield Science Museum

What is a lunar eclipse?

A lunar eclipse occurs when the Sun, Earth, and Moon are aligned in such a way that Earth blocks incoming light from the Sun, casting a shadow on the Moon—when the Moon is completely enveloped in the Earth’s shadow, this is a total lunar eclipse. This stands in opposition to a solar eclipse, when the Moon is blocking out the Sun as seen from Earth. Unlike solar eclipses, lunar eclipses are completely safe to look at with the naked eye.


Lunar eclipses can appear red due to a phenomenon known as Rayleigh scattering, where Earth’s atmosphere scatters the shorter wavelengths of blue light. Usually when we see the Moon shining, we’re seeing sunlight that has directly hit it and is reflecting back at us. But during an eclipse, that sunlight filters through Earth’s atmosphere before striking the Moon. Longer wavelength red light passes more easily through the atmosphere—as seen in the orange hues or sunrises and sunsets—making the Moon appear to be bathed in reddish light.