Lunar eclipse

when the Moon passes directly behind the Earth

A lunar eclipse is an astronomical phenomenon. It happens when the moon passes through the shadow of the Earth.. when the shadow of earth falls on to the moon is called full moon phase.... Lunar eclipses happen about twice a year, unlike total solar eclipses that are sometimes more than a year apart. They can be seen from a much larger portion of the Earth compared to solar eclipses. Lunar eclipses can last for a few hours, but total solar eclipses last only a few minutes.

A lunar eclipse occurs in two regions, an outer penumbral shadow where the sunlight is dimmed, and an inner umbral shadow, where much dimmer sunlight only exists by refraction through the Earth's atmosphere, leaving a red color.
This can be seen in different exposures of a partial lunar eclipse, for example here with exposures of 1/80, 2/5, and 2 seconds.
A solar eclipse occurs in the daytime at the new moon when the Moon is between the Earth and the Sun
A lunar eclipse occurs when the Earth passes between the Sun and the Moon

During a lunar eclipse, the Moon looks red-brown. It may be thought that the Moon is completely black because of the Earth's shadow, but no. The reddish-brown colour is because some of the Sun's light bends through the Earth's atmosphere and shines on the Moon. Refraction is greater for red light rays than for others, so red is what strikes the Moon.

Like solar eclipses, there are different types of lunar eclipses. There are total eclipses, where the moon passes completely through Earth's shadow and all of the moon appears reddish-brown. A partial eclipse occurs when only part of the moon passes through Earth's shadow and so only part of the moon appears reddish.

Lunar eclipses are safe to view with your naked eyes and also with telescopes.

Although it is safe to see the lunar eclipse with your naked eyes one should never see a solar eclipse with the naked eyes as the rays damage the retina of the eye.