With the help of an elaborate system to ensure their ballots remain confidential, two American astronauts, International Space Station Commander Edward Michael Fincke and ISS Flight Engineer and Science Officer Greg Chamitoff, who are orbiting the Earth at 17,500 miles an hour on the International Space Station voted in the US presidential election. They used their right to vote through secure digital transmission. 

Digital ballots were sent to them through Mission Control at Johnson Space Center in Houston, Texas at an altitude of some 354 kilometers (220 miles) above the planet. The passwords were directly sent to them through the local election officials. 

The encrypted ballots were returned, through the Mission control.

Jennifer Ballard, election supervisor in Harris County, Texas said, "Nobody can get into the ballot. I know because I've tested it. I tested it extensively."

The two astronauts actually wanted to convey a message as to how important voting day is. They want all their mates back on Earth to spare some time and vote. In a pre-recorded video, Station Commander Fincke said, "Voting is the most important statement Americans can make. It's a cherished right. So this election day, take time to go to the polls and vote. If we can do it, so can you."