It’s Father’s Day on Earth, and just in time for the seven-astronaut crew of NASA’s shuttle Discovery, which landed yesterday in Florida after a two-week flight to the International Space Station.

Discovery’s commander Mark Kelly and his crew are returning home to Houston, Texas today to wrap up their successful flight and reunite with their families and children on a day normally reserved for dads.

Of Discovery’s returning six-man, one-woman crew, four are parents and today’s Father’s Day return is a timely bookend of sorts for Kelly, himself a father and the identical twin brother of fellow astronaut Scott Kelly. Discovery’s May 31 launch, it turns out, occurred on the 68th birthday of his father Richard.

Meanwhile, up in orbit aboard the International Space Station, three fathers are spending today’s Day of Dads resting up after a busy docked mission with Discovery’s crew.

New station crewmember Gregory Chamitoff of NASA, who arrived aboard Discovery, has three-year-old fraternal twins Natasha and Dmitri, and had to take some extra time explaining that his son couldn’t join him on his six-month mission.

The space station’s cosmonaut commander Sergei Volkov is a father too, with a seven-year-old son. But he is also the world’s first second-generation spaceflyer to reach orbit. His own father is Alexander Volkov, a veteran cosmonaut who logged up 391 days in space on three separate space missions in the 1980s and early 1990s.

The station’s third crewmember is Oleg Kononenko, a flight engineer with four-year-old fraternal twins Alisa and Andrey. (This is a good time to mention that Discovery astronaut Ron Garan has three sons, two of them twins too!)

“I think I’m going to call them,” Kononenko told me before flight about staying in touch with his kids, adding that he tried to prepare Alisa for his six-month flight before launching into space in April. “And I told her, your dad is going to go into space for quite awhile and so I will be gone and you will be okay. Her question was, ‘Are you going to bring us any presents?’ I told her that there are no stores in space and I’m probably not going to be able to bring her anything and she seemed pretty upset by that.”