Here is the raw data showing that traceable objects of any size seem to end abruptly at about 50 AU.

The Edge of the Solar System, Allen, R. L., Bernstein, G., & Malhotra, R. 2001, The Astrophysical Journal, 549:L241-L244, 2001 March 10

In April 2001, Discover Magazine reported that scientists from University of Michigan and University of Arizona found our solar system has a sheer edge meaning matter such as asteroids, ice and other objects of all sizes appears to abruptly end. A single sun system should have a very wide dispersal of matter getting smaller and smaller for billions of miles beyond the Kuiper Belt. To find that all matter seems to end just beyond this Kuiper Belt was unexpected. Among their conclusions, the reasearchers theorized that one possible cause of the sheer edge could be the gravitational influence of some as yet undetected large mass planet, that passed within close proximity to our system at some point in the past.

Interestingly, a sheer edge is also widely thought to be typical of a binary system. In a binary system, you would expect the two companion stars gravity fields to cause any excess matter to be sheered away (ejected or captured) on a regular basis.

The sheer edge does not prove we are in a binary system as it could just as easily be caused by a very large Kuiper Belt object. Nonetheless, the data is important to developing a model of the overall action of our solar system.

Notice in this typical ejection sequence, that as the two stars near each other, their outer most particles intermingle and sheer off as they are ejected into space or captured.