The shadow of the moon or earth consists of two

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The shadow of the moon or earth consists of two distinct regions: a central umbra, where sunlight is completely blocked and a surrounding penumbra, where sunlight is only partially blocked. Lunar Eclipses If the sun, moon, and earth are completely aligned, the moon passes through earth's umbra and we a total lunar eclipse. If the alignment is not perfect, only part of the full moon passes through the umbra and we see a partial lunar eclipse.
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If the moon passes only through earth's penumbra, we see a penumbral lunar eclipse. Totality is the time during which the Moon is entirely engulfed in the umbra. Solar Eclipses If a solar eclipse occurs when the Moon is relatively close to earth in its orbit, the Moon's umbra touches a small area of Earth's surface (no more than about 270 kilometers in diameter) then you see a total solar eclipse. Surrounding the region of totality is a much larger area that falls within the Moon's penumbral shadow, a partial solar eclipse. An annular eclipse is when the moon is relatively far from the earth in its orbit, and you only see a ring of sunlight surrounding the disk of the moon. While planets usually move eastward through the constellations, they occasionally reverse course, moving westward through the zodiac...periods of Apparent Retrograde Motion. Earth orbits the Sun, but the stars are far away that stellar parallax is undetectable to the naked eye. S1: Celestial Timekeeping and Navigation The earth's precise rotation period, called the Sidereal day, is 23 hours and 56 minutes, is based on how long it takes any star to go from its highest point one day to its highest point the next Our 24 hour day, a solar day, is based on the time it takes for the sun to make one circuit around the local sky The 29 ½ day period required for each cycle of phases is called a synodic month. * A synodic month gets its name because the Sun and the Moon “meet” in the sky with every new moon. The moon's true orbital period, or sidereal month, is only about 27 1/3 days. The time it takes for Earth to complete one orbit relative to the stars is called a sidereal year. A tropical year, what our calender is based on due to the cycle of the seasons, which we measure as the time from the spring equinox one year to the spring equinox the next year. * it is about 20 minutes shorter than the sidereal year * this would make a calender out of sync with the seasons by about one day every 72 years A planet's sidereal period is the time the planet takes to orbit the sun. A planet's synodic period is the time between when it is lined up with the Sun in our sky at one time and the next similar alignment. A conjunction is when, as seen from earth, this planet will sometimes line up with Sun.
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