The Urantia Book tells us that atoms with more than 100 orbital electrons are unstable, and quickly decay. Element 101 (Mendelium) was discovered in the products of nuclear fission in 1952, and was found to have a half-life of about 30 minutes. All elements above 100 have since been found to be highly unstable. There was no adequate theoretical basis to make such a prediction at the time of receipt of the Urantia Papers. (note: the longest lived isotope of Mendelium has a half-life of 1.5 hrs)
REFERENCE: The Urantia Book, page 478
Urantia Evidence 