 |
Астронет: Астрономическая картинка дня Аналемма на восходе (с дополнением) http://variable-stars.ru/db/msg/1270245/eng |
Credit & Copyright: Tunç Tezel
(TWAN)
Explanation:
An analemma is that figure-8 curve that
you get when you
mark the position
of the Sun at the same time each day
throughout
planet Earth's year.
In this case, 17 individual images taken at 0231 UT on dates between
April 2 and September 16 follow half the analemma curve, looking east
toward the rising sun and the Caspian sea from the boardwalk in the port
city of Baku, Azerbaijan.
With the sun nearest the horizon, those dates almost span the period
between the 2012 equinoxes on
March 20 and September 22.
The northern summer Solstice
on June 20 corresponds to the top of the
figure 8 at the left, when the Sun stood at its northernmost
declination.
Of course,
this year the exposure made on June 6 contained a little
something extra.
Slightly enhanced, the little black spot on the bright solar disk near
the top of the frame is planet Venus, caught in
a rare transit during
this well-planned sunrise analemma project.
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.