** The character of Searle was originally written as a much older British man but Cliff Curtis (of Maori descent) gave the best audition.
** Creator/MichelleYeoh's audition was apparently so good that Danny Boyle told her she could have any part she wanted, even saying that he would give a GenderFlip to a male character to accommodate her. Corazon, the biologist, was her choice.
** The main eight actors were required to live in an apartment together for three months before filming (the actors unanimously say the worst cook of the bunch was Creator/MichelleYeoh). Creator/CillianMurphy's wife was pregnant during this time, so he would go back home at night. This proved helpful for his character being the youngest member and an outsider to the crew. The voice of the spaceship, Chipo Chung, was usually somewhere on the set and would be directly talking to other members of the cast, which is very appropriate for the character she's voicing.
** Also in the scene where Capa falls over in the very heavy gold spacesuit and struggles to get back up, unbeknownst to him several stage-hands held him down while he was inside the suit for the internal shots, in a attempt to make his struggling look more realistic.
** Creator/ChrisEvans was actually in freezing cold water for the scene where Mace is trying to fix the coolant. His breath rising and teeth chattering are real reactions to the cold.
** Irish actor CillianMurphy puts on an American accent as Capa.
** The Australian Creator//RoseByrne does likewise for Cassie.
** Searle is also played by New Zealander Cliff Curtis.
* FakeNationality: Pinbacker's nationality is not stated but Creator/MarkStrong uses an ambiguously Mediterranean sounding accent for him.
* ProductionPosse: The third film Creator/DannyBoyle and Creator/AlexGarland worked on after ''Film/TheBeach'' and ''Film/TwentyEightDaysLater''. Creator/CillianMurphy had also starred in the latter.
* SimilarlyNamedWorks: Creator/MarkStrong had starred in a 1999 film called ''Sunshine'' as well.
** The first draft of the script heavily featured references to God and atheism. Danny Boyle chose to downplay them, so as not to alienate potential audiences.
** Kaneda was written to be a white American. Space experts however advised Danny Boyle to change the nationality, further reflecting the international nature of space missions. The character was also called Kanada, but Hiroyuki Sanada requested the name changed to Kaneda - which is a more natural Japanese name.
** Cassie was given some of Searle's scenes and lines when Cliff Curtis had to leave filming early.
** Mace was scripted to [[spoiler: just freeze to death in the cooling tank from exhaustion]]. Danny Boyle was impressed with the character and thought of him as TheDeterminator, so [[spoiler: he wrote in Mace's leg getting trapped as a way to believably stop him from getting out]].
** A sex scene was planned between Capa and Cassie, but Danny Boyle scrapped it, feeling that the idea of sex in space was too ridiculous. Oddly enough, according to Chris Evans, Mace has been harboring a crush on Cassie for years. [[AlternateCharacterInterpretation Which adds another layer as to why Mace and Capa are continually at odds]].
* WordOfSaintPaul: According to Cliff Curtis, Searle wouldn't have fallen as far into SpaceMadness as Pinbacker if given the chance; the critical difference between them is that the former would sacrifice his beliefs, no matter how strong they may be, for the greater good of a tangible accomplishment on the scale of saving the human race, whereas the latter would not.