Judicial notice is the court's acceptance for convenience and without proof of a well-known and indisputable fact. The rules of evidence provide for certain kinds of evidence to be optionally judicially noticed. See Fed.R.Evid. 201.
A court taking judicial notice is relatively rare, and the choice by the court to take judicial notice can be questioned as to the propriety of doing so. Fed.R.Evid. 201(e).