If companies like Virgin Galactic and Blue Origin get their way, space travel will soon expand from the realm of elite astronauts to that of celebrities and the mega-rich. But there are some big issues these companies will need to grapple with before letting the likes of Justin Bieber or Rihanna onto a shuttle – like how to prepare them for the worst and what to do if somebody vomits.

Commercial spaceflights will have a totally different set of problems than flights that have come before. Until now, space has been limited to an elite few, demanding rigorous training to weed out the best of the best. “They’re looking for every conceivable way of getting rid of you, of not selecting you,” Erik Seedhouse, an aerospace scientist and author, told Inverse.

Seedhouse’s recent paper, “Passenger Training and Certification,” explores this issue. Civilian flights will want to bring in as many people as possible to make as much money as possible. So what will commercial flight training look like when there’s no space agency looking for an excuse to deny entry?

Although it may seem like it could be as simple as air travel, there are a lot of differences. That means members of the public will need to undertake rigorous training. Airplanes fly horizontally, and if the engines cut out, the pilots have a lot of different options. They can glide the plane to a safer area, during which time the pilot has a long period with breathable oxygen to make a decision.

Spaceships are totally different. A spacecraft like the Xcor Lynx re-enters at a 45-degree angle, and descent takes a matter of minutes. In an emergency situation, the pilots have little room for maneuver and could land almost anywhere. Astronauts may need to be equipped to deal with deserts, mountains, and sea.

While aircraft passengers can take off hours after arriving at the airport, and are only required to pretend to watch a safety video ahead of takeoff, pre-space-flight procedures take days. During that time, makeshift astronauts will undergo basic safety training, centrifuge training, a simulated mission, and hyperbaric training so they’ll know what to do during a rapid decompression of the spacecraft.

Then there are also medical checkups. Commercial passengers will likely need a class three medical examination, the same as airplane pilots need to get licensed. Another issue that will need to be tested for is whether passengers have any cardiovascular problems that may only present themselves in zero gravity.

Since it’ll be the commercial space travel companies testing and training potential passengers, we can’t say for sure exactly how it will all look. The Federal Aviation Administration has not given strict rules about what the training should look like, instead it’s publishing guidelines as a way of taking a hands-off approach to the industry and letting it grow.

There are a lot of issues that military-style space travel is equipped to deal with, but may prove a challenge in commercial flights. One problem is space sickness, projectile vomiting upon reaching those heady heights. 70 percent of first-time astronauts will experience motion sickness; on the third flight, around 25 percent feel motion sick. Fine for space missions, not so fine for one-off holidays.

Unfortunately, we don’t really have a way of testing on earth to find out whether someone will vomit during the flight, nor can we train people ahead of time. Pilots who are used to extreme levels of force have been known to empty their stomachs in the depths of outer space, while others who vomit from car sickness on earth may prove fine.

You just can’t tell, and that’s a big problem for commercial flights. “That’s something they don’t really talk about. If you’re trying to sell a ticket to Paris Hilton or Justin Bieber, you don’t really want to be talking about how their flight might be spoiled by somebody vomiting,” said Seedhouse. Virgin Galactic’s SpaceShipTwo flight lasts around four minutes: if somebody vomits on your camera lens in that time, it could somewhat impair your enjoyment.

Government astronauts take scopolamine. It can reduce motion sickness, but it can also make people drowsy, so they take a drug similar to amphetamine to counteract that. “Yes, you can take anti-motion sickness medication, but it may affect your enjoyment of the flight,” said Seedhouse.

Overall, though, the training will likely be a lot shorter than current astronauts would be used to, and that’s because the company wants to make the offer as attractive as possible. “Wealthy people tend not to have a lot of time on their hands. They just want to turn up at the spaceport, two or three days with family and friends, take the ride, champagne and party after. A nice five-day block of time,” Seedhouse said.

If Seedhouse was running it, he’d offer a two-week course prior to lift off. Unfortunately, this is unfeasible for commercial flights, which will skip the intensive survival training to get passengers on within days. “If you start throwing in two weeks of survival training, it’s just not gonna sell,” he said.

But for all the talk of forthcoming parties up in space, Seedhouse pointed out that it’s been 55 years since cosmonaut Yuri Gagarin became the first human to enter space, and 14 years since the Ansari X Prize for non-governmental space flight was awarded to the creators of the SpaceShipOne. “55 years and we still haven’t had a single sub-orbit commercial flight!” he said. “People really have to recalibrate their expectations.”

Photos via ESA, Getty