![]() ![]() Total - Entire Moon traverses through Earth's umbral shadow.Partial - Part of the Moon traverses through Earth's umbral shadow.(Moon is partly or completely within the penumbra) Penumbral - Moon traverses through Earth's penumbral shadow.There are three basic types of lunar eclipses: The umbral and penumbral eclipse magnitudes are given to the lower right.Ī detailed explanation of the data in the lunar eclipse figures appears in the following sections. Of Earth's penumbral and umbral shadow cones (in Earth equatorial radii) at the instant of greatest eclipse. The lower left corner lists the duration of the major phases of the eclipse in minutes.ĭepending on the eclipse type, the duration of the penumbral (P4 - P1), partial (U4 - U1), or total (U3 - U2) phases are given.īeneath the eclipse durations is the quantity gamma - the minimum distance of the Moon's center from the axis The time of greatest eclipse (Terrestrial Dynamical Time). To the top right are the Gregorian calendar date (Julian calendar dates are used prior to 1582 Oct 14) and To the top left, are the eclipse type (penumbral, partial, or total) and the Saros series of the eclipse. The geographic location where the Moon appears in the zenith at greatest eclipse is shown by aīlack dot on the meridian of greatest eclipse.Īll salient features of the eclipse figures are identified in Figure 1-1, which serves as the key to the figures on this Web site.ĭata relevant to a lunar eclipse appear in the corners of each figure. Indicates the meridian, or line of longitude, that the Moon is then crossing.Īn observer positioned somewhere on this line would then see the Moon at its highest point in the sky eitherĭue south or due north, depending on the observer's latitude and the Moon's declination. The entire eclipse is visible from the zone with no shading.Ĭonversely, none of the eclipse can be seen from the zone with the darkest shading.Īt the instant of greatest eclipse, the Moon is deepest in Earth's shadow.Ī vertical line running through the middle of the clear zone (complete eclipse visibility) of a map The map is also shaded to indicate eclipse visibility. This is accomplished using a series of curves showing where Moonrise and Moonset The bottom diagram in each figure is an equidistant cylindrical projection map of Earth showing the geographic region of visibility at each phase of the eclipse. This corresponds to the maximum phase of the eclipse, and the Moon's position at this instant is also shown in the eclipse path diagrams. The instant when the Moon passes closest to the shadow axis is known as the instant of greatest eclipse. U3 - Instant of last interior tangency of the Moon with the Umbra.U2 - Instant of first interior tangency of the Moon with the Umbra.These are the times when the total phase of the eclipse begins and ends. Tangent to the umbra (U2 and U3, respectively). Total lunar eclipses have two additional umbral contacts at the instants when the Moon's entire disk is first and last internally U4 - Instant of last exterior tangency of the Moon with the Umbra.U1 - Instant of first exterior tangency of the Moon with the Umbra.Partial lunar eclipses have two additional contacts as the Moon's limb enters and exits the umbral shadow (U1 and U4,Īt these two instants, the partial phase of the eclipse begins and ends. P4 - Instant of last exterior tangency of the Moon with the Penumbra.P1 - Instant of first exterior tangency of the Moon with the Penumbra.Penumbral lunar eclipses have two primary contacts. The Moon's orbital motion is from west to east (right to left) with respect to the shadows.Įach phase of the eclipse is defined by the instant when the Moon's limb is externally or internally tangent to The top one depicts the Moon's path through Earth's penumbral and umbral shadows with Celestial North directed up. The figure for each eclipse consists of two diagrams. The accompanying equidistant cylindrical projection map shows the geographic region of visibility during every phase The Moon's path through Earth's penumbral and umbral shadows illustrates the eclipse geometry, and Explanation of Lunar Eclipse Figures Five Millennium Canon of Lunar Eclipses Įarth will experience 12,064 eclipses of the Moon during the 5000-year period from -1999 to +3000 (2000 BCE toĪn individual diagram and visibility map for every lunar eclipse over the five-millennium interval is presented
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