Update 11/06/2018, 1:23PM: Updated to include comment from NASA.
There’s almost always an American on the International Space Station (ISS) at any given moment. So what do these astronauts do on election day? Per a Texas state ordinance, astronauts on the ISS have a way to cast their ballots in space.
According to a blog published by the Smithsonian Institute, the astronaut has to tell NASA prior to liftoff that they plan on voting in a particular election. Then, before Election Day, the astronaut gets an encrypted email ballot sent up from the Johnson Space Center Mission Control in Houston, Texas to the International Space Station (ISS). After completing the email ballot, it's sent to the astronaut's County Clerk's Office.
The legislation that makes this possible is Rule 81.35 enacted in 2000 as a part of the Texas Administrative Code, meaning that it’s a privilege only afforded to residents of Texas. Since most astronauts live in the Houston area, according to the Smithsonian article, this means that the rule applies to most American astronauts.
There’s currently one American in space: Serena Auñón-Chancellor, who’s a member of Expedition 56 on the ISS. In October, the American crew that was supposed to replace Auñón-Chancellor was forced to evacuate shortly after liftoff. As of right now, Auñón-Chancellor is scheduled to be replaced by an NASA astronaut Anne McClain so that she can return to earth, on December 13.
So, it was always the plan for Auñón-Chancellor to be in space on Election Day. But when reached by Motherboard for comment, NASA spokesperson Stephanie Schierholz said, "Serena declined to comment either way, but if she did vote that would have been the process."
Friendly reminder that you can use a HAM radio to chat with astronauts in space if you so desire, so feel free to dial up Auñón-Chancellor and chat politics, or just say “wuz up.” (Get it? Because she’s up in space?)