Dark Moon, Moon's Total Eclipse Oldest Century 21 Months

the-mohicans (36)in #science • 6 years ago

Lunar Eclipse The total of July 28 is the last lunar eclipse of the 2018 eclipse season. At the time of Total Lunar Eclipse takes place, the public can observe 3 other events ie, Moon Mini or Full Moon Apogee, Mars Opposition and the rain top Meteor Aquarid. In addition to the Aquarid meteor shower, observers can also hunt for the ongoing alpha Capricornid meteor shower.

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The whole event can be observed from July 27 afternoon after sunset until July 28 when dawn. Especially for the Total Moon Eclipse, will not happen until midnight until midnight.

Total lunar eclipse

The moon circles the Earth and with the Earth, both around the Sun. Consequently, there are times where the Sun, Earth, and Moon are in parallel position causing an eclipse. If the solar eclipse occurs when the Moon is between the Earth and the Sun, then the Moon's eclipse actually occurs when the Earth is between the Sun and the Moon.

)The configuration of the Sun-Earth - The moon during the total lunar eclipse.credit image

In the parallel configuration of the Sun-Earth - the Moon, the sunlight to the Moon is obstructed by the Earth. Usually, this configuration occurs during Full Moon. However, lunar eclipses do not occur every month reaching the full moon phase. This is due to the lunar orbit of the 5º than the Earth's orbit. As a result, there are times when the Moon does not always enter in the shadow of the Earth that causes the Sun to be blocked.

When the Moon eclipse occurs, the Moon enters the shadows of Earth's core or Earth's umbra and disappears from the view of the observer on Earth. Supposedly, the Earth is dark as the solar eclipse, because the Moon does not receive the sun's light to reflect.

But it did not happen.

The Moon Dark Eclipse

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When the Total Moon Eclipse, observers generally see the Moon does not disappear but is red like a brick or blood. The red color comes from sunlight that can pass through Earth's atmosphere and reach the Moon.

Thus, as the sun's light passes through the Earth's atmosphere, the light at the wavelength of green to purple is propagated and filtered by the atmosphere. Only red light can pass through the atmosphere and shine the Moon even though some red light is biased or deflected.

But, not every Total Moon Eclipse, the moon is reddened.

The appearance of the Moon during the total lunar eclipse varies for each eclipse. This is closely related to the path the Moon crosses in the shadows of the Earth.

The Earth's atmosphere does play an important role in continuing the Sun's light so that observers can still see the Moon red during an eclipse. However, in Earth's atmosphere, there is also dust, organic matter, and even volcanic ash. So if there is a dreadful eruption of the volcano and its dust into the atmosphere in large numbers, the eclipses that occur can be very dark red for several years.

It's from the influence of the atmosphere.

Based on the scale of Danjon, the appearance of the Moon can indeed span from L scale from 0 to 4. For Danjon scale 0, the moon appears very dark or disappears from the view of the observer when the Moon crosses the center of the Earth's umbra. For a scale of 1 - 4, the color of the Moon stretches from the dark, dark red, brick red to a very bright orange / red color.

Total Moon Eclipse July 28, 2018, is special because the Moon will pass right in the middle of Earth's umbra. Although the eclipse's appearance still depends on Earth's atmospheric conditions, it is estimated that the Moon's Eclipse Total this month will be dark red especially the southern part of the Moon that crosses right in the middle line of the Earth's umbra. These conditions include rare.

The Oldest Total Moon Eclipse in the 21st Century

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In addition to looking dark red, this lunar eclipse will have the longest duration during the 21st century (2001 - 2100) ie 103 minutes. The long duration occurs because apart from traversing the center of the Earth's umbra, the Moon is also at the furthest point from Earth or apogee. In general, Apogee Full Moon moon phenomenon is known as the Mini Month or Micro Moon because the Moon disk will appear 14% smaller than the Full Moon when in the perigee a.k.a Super Moon.

The moon reaches its farthest point on July 27, 2018, or 14 hours 38 minutes before a total lunar eclipse occurs. When compared to the average distance of the Moon of 384,400 km, that means the Moon lags 21,823 km or the Moon disk will appear 5.6% smaller than the average. When compared to the Moon when it is at the closest distance from Earth, the Moon disc will appear 11.2% smaller.

Although the Moon's disks appear smaller, there is not much difference that observers can see.

The effect of the eclipse during the full moon apogee, the total lunar eclipse duration was so much longer. For a total lunar eclipse of July 28, 2018, the total duration will last for 1 hour 42 minutes 57 seconds, while the total lunar eclipse January 31, 2018, when the Moon in perigee, the duration is only 1 hour 16 minutes 4 seconds.

The total lunar eclipse before July 21, 2018, is a total lunar eclipse July 16, 2000, ie for 01 hours 46 minutes 24 seconds which at once lunar eclipse total the longest 20th century. The next longest total duration is a total lunar eclipse June 9, 2123, with a duration of 1 hour 46 minutes 6 seconds which is also the longest total lunar eclipse in the 22nd century.

Similarly, the three eclipses occur when the Moon crosses the Earth's umbra center in June - July as the Earth is in the area of its farthest point from the Sun, and the Moon is also in the furthest point area of the Earth.

Under Kepler's 3rd Law, in elliptical paths, an object moves faster as it is near the center of mass and slower when away from the center of mass.

Well, when the Moon is in apogee, a great distance causes the Moon whose disc becomes smaller, it will move more slowly across the Earth's umbra. In addition, the Earth's position that is in the aphelion or the furthest point from the Sun also causes the Earth's umbra to reach its maximum length and width. Therefore, it takes longer for the Moon to get out of the shadows of the Earth's core.

The total lunar eclipse of July 28, 2018, is generally observable from South America, Europe, Asia, Australia, Africa, the Atlantic Ocean, Indian Ocean and Antarctica.

)Eclipse visibility, July 27, 2018.credit image

For a total lunar eclipse July 28, the Moon will begin to enter the Earth's shadow and spend 3 hours 54 minutes in the Earth's umbra. The overall lunar eclipse will occur for 6 hours 13 minutes with a total eclipse duration of 1 hour 43 minutes. Total Moon Eclipse is the longest since 18 years ago and will be surpassed 105 years.

If weather permits, do not miss the longest Total Moon Eclipse in the 21st century. In addition to the Total Moon Eclipse, observers can also watch the Martian opposition as well as the delta aquariids delta meteor shower peak that will appear to come from the constellation Aquarius. If lucky, you can also watch the alpha Capricornid meteor shower that is heading to the summit on July 30th.