Credit & Copyright: Adrianos Golemis
Explanation:
Does the Sun return to the same spot on the sky every day? No.
A better and more visual answer to that question is an
analemma,
a composite image taken from the same spot at the same time over the course of a
year.
The featured weekly analemma was taken despite
cold temperatures and
high winds near the
Concordia Station in
Antarctica.
The position of the Sun at 4 pm was captured on multiple days in the digital composite
image,
believed to be the first analemma constructed from
Antarctica.
The reason the image only shows the Sun from September to
March is because the Sun was below the horizon for much of the rest of the year.
In fact, today being an
equinox, the Sun rises today at the
South
Pole
after a six month absence and won't set again until the next
equinox in March, baring
large atmospheric
refraction effects.
Conversely, today the Sun sets at the
North Pole
after half a year of continuous daylight.
For all of the Earth in between, though, the
equinox means that today will have a nighttime and daytime
that are both 12 hours long.
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NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
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Публикации с ключевыми словами:
equinox - Равноденствие
Публикации со словами: equinox - Равноденствие | |
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