http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Mercury is the closest planet to the Sun, which makes it both difficult to observe and to visit with a probe. To minimize this problem Messenger is on a circuitous path using the gravitation from both Venus and Earth to help it approach Mercury at an oblique angle to the Sun.
Title from resource description page (viewed July 15, 2014).
In short : a lesson on almost everything ; Episode 129