The Midnight Sky was filmed in Santa Cruz de Tenerife, Spain
Roque de los Muchachos Observatory
In movie
Scene where Jean and Augustine meet after some time. She tells Augustine to take care of himself.
Real
Scene was shot Roque de los Muchachos Observatory - or in Spanish: Observatorio del Roque de los Muchachos, ORM - is an astronomical observatory located in the municipality of Garafía on the island of La Palma in the Canary Islands. The observatory site is operated by the Instituto de Astrofísica de Canarias, based on nearby Tenerife. ORM is part of the European Northern Observatory. The building of the observatory traces to 1969.
The Barbeau Observatory in the movie is not real. It partly resembles the Gran Telescopio Canarias which is close to the location where this scene was filmed.
Santa Cruz de Tenerife