Original sentence: Astrophysicists such as Amy Mainzer of NASA's JPL are currently working to answer these pressing questions.However, the existence of Planet X will be disputed until future imaging projects of the Kuiper belt edge can either confirm or rule out its existence.It has been hypothesized that this may be due to a large object, popularly called Planet X.The Kuiper belt has a sudden decrease in object density, called the edge.The gravitational field of Planet X would huddle the Kuiper Belt objects together forming the edge