Joseph Wright of Derby was an informal rather than a formal member of the Lunar Society of Birmingham, or as Olga Baird describes him, “a Lunar Satellite”.
Baird in her biographical essay on Joseph Wright of Derby (1734-1797): Painter of the Enlightenment and the Industrial Revolution states that: “Wright was never a formal member of the Lunar Society but his long friendship with John Whitehurst (1713-1788) and Erasmus Darwin (1731-1802) certainly made him a Lunar Satellite.”
Also, that: “Unlike many of the European groups of intellectuals representing the movement of the Enlightenment the Lunar Society of Birmingham was fortunate to inspire a great artist, who was not only able to produce likenesses of its members, but also captured the pathos and excitement of experiment and exploration and discovery.”
Source: Revolution https://www.revolutionaryplayers.org.uk/joseph-wright-of-derby-art-the-enlightenment-and-industrial-revolution/
Picturing The Pacific 