The Solar Polar Orbiter (SPO) Technology Reference Study (TRS)
examines the feasibility of a mission to obtain true solar polar
orbit at an altitude of less than 0.5 AU to perform remote
sensing of the Sun and in situ measurements of the surrounding
environment. The Solar Polar Orbiter The Solar Polar Orbiter has
the following scientific objectives: The Solar Polar Orbiter
consists of a single spacecraft, launched on a Soyuz Fregat 2B
from Kourou, French Guiana. The spacecraft will utilize a solar
sail to lower its orbit to less than 0.5 AU before raising its
inclination. After about 4 years the SPO spacecraft will achieve
an inclination of approximately 83 degrees in the ecliptic
coordinate frame. At this point the sail will be detached in
order to perform undisturbed scientific measurements. The
preliminary concept for SPO employs a square solar sail with a
total area of approximately 25 000 m². The characteristics of
the sail are given in the table below. The preliminary mass
budget is given in the table b