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Астронет: Астрономическая картинка дня Зеленый луч: видео http://www.astronet.ru/db/msg/1782970/eng |
Credit & Copyright: Paolo Lazzarotti
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 on video last month as the Sun set beyond the
Ligurian Sea
from Tuscany,
Italy.
The second sequence in the
featured video shows the
green flash
in real time, while the first is sped up and the last is in
slow motion.
The Sun itself does not turn
partly green -- the effect is caused by layers of the
Earth's atmosphere acting like a prism.
Discovery + Outreach:
Graduate student research position open for APOD
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.