Explanation:
Venus, the second closest planet to the Sun,
is by far the brightest of the
three planets gathered in this weekend's
western sky at sunset.
It has also proven to be a popular
way-point for spacecraft headed for the
gas giant planets
in the outer reaches of the solar system.
Why visit Venus first?
Using a gravity assist maneuver,
spacecraft can swing by planets and gain energy during their brief
encounter, saving fuel for use at the end of
their long interplanetary voyage.
This
colorized image of Venus was recorded by the Jupiter-bound
Galileo spacecraft shortly after its gravity assist flyby of Venus
in February of 1990.
Galileo's glimpse of
the veiled planet shows structure in
swirling sulfuric acid clouds.
The bright area is
sunlight glinting off the upper cloud deck.