The four new elements, all of which are synthetic, were discovered by slamming lighter nuclei into each other and tracking the following decay of the radioactive superheavy elements.
Like other superheavy elements that populate the end of the periodic table, they only exist for fractions of a second before decaying into other elements.
I've read theories that the eighth row may contain superheavy elements that are stable. When they are discovered, it will herald a wondrous era of discovery for humankind. I'm hoping it happens within my lifetime.