Masterpiece by Jan Matejko makes a rare visit to the National Gallery Jan Matejko, The Astronomer Copernicus. Conversations with God, 1873. Oil on canvas, 226 × 315 cm Frame: 293 ×382 × 24 cm. The Jagiellonian University Museum, Kraków (MUJ 2715851/I) Photo by Grzegorz Zygier. LONDON .- An iconic painting of astronomer Nicolaus Copernicus, by the most famous Polish painter of the 19th century, Jan Matejko, is making a rare visit to the National Gallery, the first time it will ever have been seen in the UK. The 10-foot wide painting, which rarely leaves its home in the Senate Chamber of the Jagiellonian University, Kraków, is part of a new exhibition introducing visitors to the work of Jan Matejko (18381893). Despite being largely unknown outside his homeland, this highly original and distinctive artist is widely regarded as the national painter of Poland.