Credit & Copyright: Dario Giannobile
Explanation:
How does the sky turn dark at night?
In stages, and with different characteristic colors rising from the horizon.
The featured image shows, left to right, increasingly late
twilight
times after sunset in 20 different vertical bands.
The picture was taken last month in
Syracuse,
Sicily,
Italy,
in the direction
opposite the Sun.
On the far left is the pre-sunset upper sky.
Toward the right, prominent bands include the
Belt of Venus,
the Blue Band, the
Horizon
Band, and the Red Band.
As the dark shadow of the Earth rises, the colors in these bands are
caused
by direct sunlight reflecting from air and
aerosols in the
Earth's atmosphere,
multiple reflections sometimes involving a
reddened sunset, and
refraction.
In practice, these bands can be diffuse and hard to discern,
and their colors can depend on
colors near the setting Sun.
Finally, the Sun
completely sets and the sky becomes dark.
Don't despair -- the whole thing will happen in reverse when the
Sun rises again in the morning.
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
Январь Февраль Март Апрель Май Июнь Июль Август Сентябрь Октябрь Ноябрь Декабрь |
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Публикации с ключевыми словами:
закат - пояс Венеры
Публикации со словами: закат - пояс Венеры | |
См. также:
Все публикации на ту же тему >> |