The longest total
lunar eclipse of the century will be today. While the full eclipse will be over
6 hours, the total lunar eclipse 2018 - when the moon will be in the middle of
Earth's shadow - will last for 1 hour and 43 minutes. The total lunar eclipse today
will be the longest such eclipse for the next century, until June 9 2123.
Moreover, today's eclipse is also the Blood Moon ~ remember we enjoyed seeing this on 31st
Jan 2018.
A
lunar eclipse is a celestial event which happens when Earth lines up directly
between the sun and the moon. When this happens, Earth blocks the light from
the sun to the moon. Earth's shadow then falls on the moon. During a lunar
eclipse, we can see Earth’s shadow on the moon.
An eclipse occurs any time a
planet or moon passes between another planet, moon or the sun. Depending on
their orbits, they can be total or partial. They can last for
several hours, but it is rare for a period of total eclipse to last longer than
100 minutes. At least two lunar eclipses
happen every year.
A total
lunar eclipse happens when the whole moon enters Earth's shadow. Some sunlight
still reaches the moon, but first it goes through Earth's atmosphere. The
atmosphere filters out most of the sun’s blue light, so the moon looks red.
On Friday, July 27th,
a "blood moon" lunar eclipse will happen. The full moon passes
through the shadow of Earth. What is special about this particular eclipse is
that it will change the color of the moon to a reddish color. Obviously that is
where the term "blood moon" comes from but, this one will happen for
about 103 minutes. At the same time that
the longest "blood moon" in history occurs, Mars will be only 35.9
million miles from Earth. According to experts, this is the closest that the
"red planet" has been to Earth in 15 years.
You
all would have heard the phrase : ‘Once
in a blue moon’ ~ informally it would mean ‘very rarely’. Synonyms:
hardly ever, almost never, scarcely ever, rarely, very seldom. Interestingly, the colour of moon is never
blue. A blue moon is an additional full moon that appears in a subdivision of a
year: either the third of fourth full moon in a season, or the second full moon
in a calendar month. The phrase has nothing to do with the actual color of the
moon, although a literal "blue moon" (the moon appearing with a tinge
of blue) may occur in certain atmospheric conditions.
One lunation (an
average lunar cycle) is 29.53 days. There are about 365.24 days in a tropical
year. Therefore, about 12.37 lunations (365.24 days divided by 29.53 days)
occur in a tropical year. Each calendar
year contains roughly 11 days more than the number of days in 12 lunar cycles.
The extra days accumulate, so every two or three years (seven times in the
19-year Metonic cycle), there is an extra full moon. The extra full moon
necessarily falls in one of the four seasons, giving that season four full
moons instead of the usual three, and, hence, a blue moon.
Now getting back to
“super blue blood moon” ~ it will be at
its attractive best to those watching !
as the light from the sun passes through the Earth's atmosphere, it will
cast a crimson sheen over the moon. Dr Mark Birkinshaw, a professor of
Cosmology and Astrophysics at the University of Bristol, told MailOnline that
the phenomenon is the same reason the sun appears a dark shade of red when it
sits low in the sky. 'The light that passes through the Earth's atmosphere hits
the Moon and then gets reflected back to us, and it will be red,' he said. 'Technically,
the red light is less scattered by the atmosphere than the blue, so more of it
gets through.
'From the Moon, the
Earth would appear to totally-eclipse the Sun, and would show as a dark shadow
with a bright red ring around it.' The total eclipse begins at 7:30 pm UTC
(8:30 BST), and ends at 9:13 pm UTC (10:13 BST). The peak of the eclipse will
occur at 8:22 pm UTC (9:21 BST). Only those in the Eastern Hemisphere will be
able to view the upcoming event, with people in Europe, Africa and Asia getting
the best seats for the lunar show. Skygazers in South America will be able to
see part of the final stages of the eclipse just after sunset tonight. In contrast, New Zealanders will be able to
watch the start of the eclipse before sunrise tomorrow morning.
The lunar event
will not be visible at all in the United States, as the moon will be invisible
below the horizon throughout the duration of the eclipse. By the time it rises
across the states, the eclipse will have concluded. Parts of central Asia, the
Middle East and Eastern Africa will see the lunar eclipse in its entirety. The
UK falls slightly outside of the ideal viewing range, meaning people will see
the total eclipse for only 84 of the 103 total minutes. This is due to the moon
being below the horizon in Britain when the eclipse begins.
To get the best
view of the eclipse, make sure you are in an area with low-light pollution. For
example, high vantage points in a built-up area, or ideally, a trip to the
countryside should provide the best view. Those who want to photograph the
lunar transit will be able to do so with a bit of patience, a telescope and the
right app.
Happy moon watching !
The first part of lunar eclipse is expected to start at around 11:44 PM
IST on July 27. The Moon will turn red only at the highest point of the total
lunar eclipse, which starts around 1 AM on the night of July 28. The phenomenon
should last till 2:43 AM IST on July 28.
Those planning to watch this celestial event should note that unlike
solar eclipse, one does not need to cover their eyes with protective filters to
view the Blood Moon.
With regards – S.
Sampathkumar
27th
July 2018.
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