The 61-year-old business school professor signed up back in 2005 for the promise of five minutes in zero-gravity, paying $250,000 (£190,500) to travel beyond the earth's atmosphere.
Now the company that sold her the ticket, Virgin Galactic, says it will finally begin flights this year. Its founder, Sir Richard Branson, will be on the first trip, and Mrs Maisonrouge won't be far behind.
"Hopefully it will be as amazing as I think," says Mrs Maisonrouge.
If all goes to plan, Virgin Galactic will be the first private company to take tourists into space. The company says 600 people have already purchased tickets, including celebrities like Justin Bieber and Leonardo DiCaprio.
But rival firms are close behind. Blue Origin, started by Amazon founder Jeff Bezos, has also starting speaking to possible passengers for trips it hopes to start this year, while SpaceX, founded by Tesla's Elon Musk, announced in 2019 that a Japanese billionaire would be its first passenger for a trip around the moon.