ok, so it’s like what mark-imafckingastronaut-watney said: mark was the media relations guy for the crew
which means that en route to mars mark was
trying not to swear while making videos responding to students’ questions and explaining how hermes created artificial gravity
tweeting about the hermes’ location in the sky relative to various points on earth and telling astrophotographers to make sure to get his good side
singing to his plants, which johanssen catches on camera and posts to vine
convincing everyone on beck’s birthday to jump out at beck at various points in the day and yell “HAPPY BIRTHDAY” when he’s least expecting it. he creates a compilation video of beck’s reactions. in retaliation, on mark’s birthday, beck convinces lewis to blast her disco music through the speakers in the 0g plant lab because he knows mark is stuck there all day for a time-sensitive experiment. beck films mark at various points in the day getting progressively more desperate until mark creates make-shift earmuffs from spare sponges and duck tape.
instagramming pics of the pale blue dot to people on earth with captions like “if you don’t think that’s the tightest shit then get outta my face” before NASA quickly changes the caption
posting youtube videos of he and martinez having competitions to see who can make it to the highest rung on the ladder when jumping from one of the rotating capsules up towards the center of the ship where there’s no gravity. 2 weeks before they get there, martinez manages to jump high enough to get pulled up to the rotating capsule opposite them and mark catches the whole thing on the GoPro and goes fucking insane and jumps up and down and screams “HOLY FUCK, YOU FUCKING DID IT! HE FUCKING DID IT! DID YOU JUST SEE THAT SHIT?! MARTINEZ I GOT IT ON FUCKING CAMERA HOLY SHIT!!” and he posts it to the mission youtube account but nasa replaces the audio with background music because they can’t bleep out all of his swearing without it sounding like an episode of jerry springer
getting everyone to learn the happy birthday song in german to sing to vogel on his birthday. vogel tears up, and watney posts it to youtube with the caption: “He’s only crying because we butchered the German language so badly. Alles Gute zum Geburtstag, buddy.”
and then after he’s stranded on mars, all of the videos and pics and tweets go viral because more people care about it now. but because he’s revealed so much of his personality through everything, it makes everyone feel like they know him. and at that point, turning away is no longer an option. people feel that they must #BringHimHome