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Астронет: Астрономическая картинка дня Зеленый луч от Солнца http://variable-stars.ru/db/msg/1180775/eng |
Credit & Copyright: Pekka Parviainen
(Polar Image)
Explanation:
Many think it is just a myth.
Others think it is true but its cause isn't known.
Adventurers pride themselves on having seen it.
It's a green flash from the Sun.
The truth is the
green flash
does exist and its cause is well understood.
Just as the setting
Sun disappears completely from view,
a last glimmer appears startlingly
green.
The effect is typically visible only from locations with a low,
distant horizon, and lasts just a few seconds. A green flash is also visible for a rising
Sun, but takes better timing to spot.
A dramatic green flash was caught in the
above photograph in 1992 from
Finland.
The
Sun itself does not turn
partly green, the effect is caused by layers of the
Earth's atmosphere acting like a prism.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.