Opposition (planets) Sun. An inferior conjunction occurs when the two planets align on the same side of the Sun. At inferior conjunction, the superior planet is "in opposition" to the Sun as seen from the inferior planet (see the diagram). Opposition (planets) In positional astronomy, two astronomical objects are said to be in opposition when they are on opposite sides of the celestial sphere, as observed from a given body (usually Earth). A planet (or asteroid or comet) is said to be "in opposition" when it is in opposition to the Sun. Because most orbits in the Solar System are nearly coplanar
Stability of the Solar System planets, it could substantially disrupt the Oort cloud which could cause major comet activity throughout the solar system. There are at least a dozen other stars that have a potential to make a close approach in the next few million years. Project LONGSTOP (Long-term Gravitational Study of the Outer Planets) was a 1982 international consortium of Solar System dynamicists led by Archie Roy. It involved creation of a model on a supercomputer, integrating the orbits of (only) the outer planets. Its results revealed several curious exchanges of energy between the outer planets, but no signs of gross instability. Another project