Predictions and tests are the central themes of Science.
Theories make predictions. Observations test the predictions.
If new data falsifies a theory, then the theory either must be
modified to account for the new data or it must be discarded.
Our theory for Sedna's orbit predicts that we should find other
distant objects with orbits similar to Sedna's. We also predict
that there should be some closer objects with orbits that are
much more highly inclined than Sedna to the ecliptic, the plane
of the Earth's orbit.
Although there are too few objects to provide a great test of
the theory, at least one other object has an orbit similar to
those we predicted.
Lynne Allen and her collaborators discovered 2004 XR190,
an object with a heliocentric distance of 57 AU and an inclination
of 47 degrees.