May 2069 lunar eclipse explained

bgcolor=#e7dcc3 colspan=2Total Lunar Eclipse
May 6, 2069
align=center colspan=2
The Moon passes west to east (right to left) across the Earth's umbral shadow, shown in hourly intervals.
align=center bgcolor=#c0d0e0132 (33 of 71)
align=center bgcolor=#c0d0e00.272
align=center bgcolor=#c0d0e01.327
align=center bgcolor=#c0b0e0 colspan=2Duration (hr:mn:sc)
align=center bgcolor=#b0a0e0 Totality 01:24:16
align=center bgcolor=#c0a0e0 Partial 03:46:11
align=center bgcolor=#d0d0e0 Penumbral 06:08:07
align=center bgcolor=#a0d0e0 colspan=2Contacts
align=center bgcolor=#d0d0e0 P1 06:03:38 UTC
align=center bgcolor=#c0a0e0 U1 07:14:38 UTC
align=center bgcolor=#b0a0e0 U2 08:25:35 UTC
align=center bgcolor=#a0a0e0Greatest 09:07:43 UTC
align=center bgcolor=#b0a0e0 U3 09:49:42 UTC
align=center bgcolor=#c0a0e0 U4 11:00:49 UTC
align=center bgcolor=#d0d0e0 P4 12:11:45 UTC

The eclipse occurs in the constellation Libra at the ascending node of the moon's orbit.
A total lunar eclipse will take place on May 6, 2069. The eclipse will be a dark one with the southern tip of the Moon passing through the center of the Earth's shadow. This is the first central eclipse of Saros series 132.

It is the first of two total lunar eclipses in 2069, the second occurring at the descending node of the Moon's orbit will be on October 30, which will also be a central total eclipse.

It is the third of an almost tetrad, the others being 17 May 2068 (P), 9 Nov 2068 (T) and 30 October 2069 (T).

Visibility

The eclipse will be visible after sunset over Australia and begin before sunset over far eastern Asia, and be seen in the predawn hours over western North and South America.

The Moon will also occult the bright star Alpha Librae as seen from the southern hemisphere a few hours before greatest eclipse.[1]

Related lunar eclipses

Lunar eclipses are related by many different eclipse cycles. The Saros cycle (18 years and 10 days) repeats the most consistently due three coinciding periods, and continue over 70 events (1200+ years). Eclipses are identified by a Saros number and a member index within each series.

The lunar year (354 days) and Metonic cycles (19 years) are short period last only 8 to 10 events. The Metonic cycle is equal to one Saros cycle plus one lunar year, and so the two series progress in parallel.

The Inex cycle (29 years minus 20 days) can last tens of thousands of years, so long that long perturbations in the Moon's path must be taken into account for prediction. Also the eclipse qualities are less inconsistent because the Moon is at different significantly positions in its elliptical orbit in sequential events. Similarly for the shorter Tritos cycle (10 years and 31 days), repeats less consistently for the same reason.

Lunar year series

This eclipse is the third of four lunar year eclipses occurring at the Moon's ascending node.

The lunar year series repeats after 12 lunations or 354 days (Shifting back about 10 days in sequential years). Because of the date shift, the Earth's shadow will be about 11 degrees west in sequential events.

Half-Saros cycle

A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros).[2] This lunar eclipse is related to two total solar eclipses of Solar Saros 139.

See also

External links

References

Notes and References

  1. Jean Meeus, G. P. Konnen, "Occultations of Bright Stars by the Eclipsed Moon", Journal of the British Astronomical Association, Vol. 85, No. 1, pp. 17-24 (1974).
  2. Mathematical Astronomy Morsels, Jean Meeus, p.110, Chapter 18, The half-saros