John A. Mather is not widely recognized as a prominent figure in the field of visual arts, which is the primary domain of art history. Instead, he is known as an American astrophysicist who was born in Roanoke, Virginia. Mather is renowned for his work in cosmology and his significant contribution to the Cosmic Background Explorer Satellite (COBE) project, for which he, along with George F. Smoot, was awarded the Nobel Prize in Physics in 2006. The COBE project helped cement the Big Bang theory by measuring the heat radiation from the early universe, also known as the cosmic microwave background radiation.
Given that Mather's primary field is astrophysics, there may be some confusion if there is another John A. Mather who is an artist, as such an individual does not have a prominent presence in the historical record of art. If the John A. Mather you are referring to is indeed an artist, additional context or information would be needed to provide a relevant biography.
In the absence of further details, it is important to note that in the context of art history, individuals with similar or identical names can sometimes be confused or conflated, and without specific information such as the time period of activity, nationality, or artistic style, it is challenging to provide an accurate biography for someone who might be lesser-known or not widely documented in art historical texts.