Definition of "astronomical"

Finally, all men saw that astronomical knowledge lied not, and they awaited the comet.

1839, Edgar Allan Poe, The Conversation of Eiros and Charmion

Drawings and pictures are more than mere ornaments in scientific discourse. Blackboard sketches, geological maps, diagrams of molecular structure, astronomical photographs, MRI images, the many varieties of statistical charts and graphs: These pictorial devices are indispensable tools for presenting evidence, for explaining a theory, for telling a story.

2012 March, Brian Hayes, “Pixels or Perish”, in American Scientist‎, volume 100, number 2, archived from the original on 19 February 2013, page 106

At the moment he wondered why anyone would want to visit Khatka, let alone pay some astronomical sum for the privilege.

1959, Andre Norton, Voodoo Planet - Chapter IV

The cost of such a work now, of course, would be astronomical.

1962 June, “Letters to the Editor: Diesel suburban services in Bristol”, in Modern Railways, page 430