The two NASA astronauts who were initially going up to the International Space Station (ISS) for nine days but ended up staying there for 286 days weren't paid any overtime.

In a recent article by The New York Times, a NASA spokesperson revealed the two NASA astronauts, Suni Williams and Butch Wilmore, received a regular 40-hour-per-week salary, with no additional pay for holidays or weekends, despite the obvious egregious overtime they both ensued. Additionally, Mike Massimino, a veteran of two Space Shuttle missions, said, "[There's] no hazard pay, there's no overtime, there's no comp time," and ultimately, "there's no incentive to stay in space longer."
However, astronauts do receive incidental amounts for reach they're in space, but since Suni and Butch were on a long-term stay, it only equated to about $5 per day, which totals out to just $1,430 for the entire duration of the trip - 286 days.
For context, a NASA astronaut receives approximately $152,258 per year, according to NASA's 2024 pay rates. Since they are categorized as federal employees on a work trip, their food, transportation, and lodging are provided by NASA. These figures aren't surprises to the astronauts themselves, as they are well aware of the risks and the financial compensation they receive to endure them.
"When NASA astronauts are aboard the International Space Station, they receive regular 40-hour workweek salaries," NASA told Fortune in a statement. "While in space, NASA astronauts are on official travel orders as federal employees, so their transportation, lodging, and meals are provided."
But NASA astronauts aren't likely to pursue adventures to the ISS and beyond for financial gain, as these are people who are highly educated and could be in a much better-paying field if they so choose.