LUNAR ECLIPSES

Credit: Johannes Schedler TABLE OF CONTENTS:

SAFETY ANATOMY OF A LUNAR ECLIPSE PENUMBRAL ECLIPSES PARTIAL ECLIPSES TOTAL ECLIPSES REVIEW ECLIPSE TYPES DANJON SCALE NEXT ECLIPSES Click logo anytime MORE to come back here:

Credit: Johannes Schedler SAFETY

Lunar eclipses are perfectly safe to view without protection.

You can use your eyes, binoculars or telescopes.

Be patient, it takes time for the lunar disc to change color.

Credit: Johannes Schedler Credit: starrynight.com ANATOMY OF AN ECLIPSE

Umbra

Penumbra

Frontal view of Earth’s shadow.

A lunar eclipse happens when Earth comes between the Sun and the Moon, projecting its shadow onto our satellite. Shadows come in 2 forms: the penumbra which is the outmost and is partly- shaded; and the umbra, which is the innermost and is fully-shaded. PENUMBRAL ECLIPSE

Umbra

Penumbra

Penumbral eclipses can be total, when the whole Moon enters the penumbra; or partial, when a fraction of the Moon enters the penumbra. They are difficult to detect because the Moon only changes its brightness a bit. Example of a partial penumbral eclipse.

Credit: Hong Kong Space Museum PARTIAL ECLIPSE

Umbra

Penumbra

Partial umbral eclipses take place when a fraction of the Moon enters the umbra, and of course, in its way it also enters the penumbra. When in the umbra, the lunar disc will change color or become very dark. Example of a partial umbral eclipse.

Credit: Rodney Pommier TOTAL ECLIPSE

Umbra

Penumbra

Total umbral eclipses take place when all of the Moon enters the umbra, and of course, in its way also the penumbra. When in the umbra, the lunar disc will change color or become very dark. Example of a total umbral eclipse. REVIEW ECLIPSE TYPES

Credit: Tom Ruen / Wikipedia Review of lunar eclipse types DANJON SCALE

1 2 3 4 5

During the maximum of a total umbral eclipse we can see what color the lunar disc has taken and assign a value according to the Danjon Scale.

Credit: Tim Trott DANJON SCALE

0 very dark totality, with the Moon almost invisible

1 dark/gray/brownish, details distinguishable with difficulty

2 deep red/rust, very dark central shadow, bright outer edge

3 brick-red with a bright or yellow rim

4 bright copper-red/orange, with a bluish & very bright rim NEXT ECLIPSES

Visible in the continental USA

Date Type

March 23, 2016 penumbral

February 11, 2017 penumbral

January 31, 2018 total MORE

Our website: www.astro.ucr.edu

Facebook: facebook.com/astroucr

Twitter: @astroucr