Астронет: Астрономическая картинка дня Огнепад в лунном свете http://www.variable-stars.ru/db/msg/1831127/eng |
Credit & Copyright: Tara Mostofi
Explanation:
On certain dates in February, an
elusive firefall can be spotted at sunset in
Yosemite National Park,
when water flows, the weather cooperates
and the direction to the setting Sun is just right.
Often photographed from vantage points below, at the right moment the park's
seasonal Horsetail
Fall
is isolated in the shadows of the
steep walls of El Capitan.
Then, still illuminated with rays of reddened sunlight
the waterfall briefly takes on a dramatic, fiery appearance.
But a
Horsetail
firefall
can be photographed by moonlight too.
Even more elusive by moonlight, the firefall effect can also be seen
when a bright Moon sets at the right direction along the western horizon.
And skies were clear enough for this
well-planned imaging of an
ephemeral Horsetail firefall,
lit by a bright gibbous Moon setting in the early morning hours of April 15.
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.