Later this year, a SpaceX Falcon 9 rocket will launch more than 70 satellites into orbit — the largest batch of satellites sent into space at one time from one of the company’s vehicles or of any other US rocket company. Dubbed the SSO-A mission, the flight is scheduled to take off from Vandenberg Air Force in California in late 2018, though an exact date has yet to be determined.

The epic satellite rideshare was coordinated and brokered by Spaceflight Industries — a company dedicated to finding launch “real estate” for small satellites that need to get into space. Spaceflight has become a go-to resource for many small satellite manufacturers, as they have limited options for getting their hardware into orbit. Huge rockets like the Falcon 9 or Atlas V are typically far too big and expensive to send a handful of tiny satellites into space. For the last decade, these companies have only really had just two options: launch their satellites as cargo to the International Space Station, where they are later deployed, or hitch a ride on the flight of a larger satellite.

Spaceflight bought this entire Falcon 9 vehicle outright in 2015, and has since been filling up the launch manifest

Spaceflight will work with manufacturers to find extra room on rockets that are already scheduled to launch bigger payloads into orbit. The company will then figure out a way to help integrate those small satellites into the mission, so that multiple payloads can go up at once. So far, Spaceflight has found rides for more than 140 different satellites on multiple launch vehicles. The company even helped to book room for 20 satellites on one of the most massive rocket rideshare yet, when an Indian PSLV (Polar Satellite Launch Vehicle) rocket launched 104 satellites into orbit in February 2017.

Image: Spaceflight

The difference with this upcoming Falcon 9 flight from other rideshares is that Spaceflight bought this entire Falcon 9 vehicle outright in 2015, and has been filling up the launch manifest ever since. Now, a total of 71 satellites are scheduled to fly, according to new details released by Spaceflight today. These include 15 larger microsatellites, and 56 smaller standardized satellites known as CubeSats. The probes range in weight from 11 pounds to 660 pounds. Up to 18 different countries have payloads on the flight, including the United States, Australia, Thailand, Poland, and more. And about three-fourths of these satellites are commercial payloads, while universities and even a high school have their own hardware going up. Two art exhibits will also be onboard.

All of the satellites are slated to go into a low path above Earth known as a sun-synchronous orbit. It’s a route that allows satellites to pass over the same patch of the Earth’s surface at the same time each day. Once the Falcon 9 launches, it will take between six to eight hours to deploy all 71 satellites into this orbit. Deploying all of these probes at the right time will be an incredibly complex sequence of events, according to Curt Blake, president of Spaceflight’s launch services group. The satellites will be loaded onto a large structure known as a payload stack that is mounted on top of the rocket. This stack is equipped with various mechanisms that will jettison the satellites one by one at the right time in space.

Once the Falcon 9 launches, it will take between six to eight hours to deploy all 71 satellites

“Probably the biggest technical challenge is sequencing all of the spacecraft off the payload stack,” Blake tells The Verge. “When you sequence that launch, you have to do it in a well thought out and organized way, so you don’t end up having spacecraft coming back, contacting each other, and causing space debris. We spent a lot of time modeling that and tinkering with the sequencing to make sure it all comes off without recontact.”

The satellites being integrated together for launch at Spaceflight’s Washington facility

Image: Spaceflight

Not only does Spaceflight figure out the infrastructure for its flights, but it also helps satellite companies navigate the various licenses they need to get before heading into space. US satellite companies need licenses from the Federal Communications Commission, for instance, in order to reserve a small amount of radio frequencies needed to communicate with their space probes. Spaceflight is being extra vigilant about licensing lately, too, ever since one of its customers allegedly sent up four satellites that had been denied an FCC license.

“I think the customer in that case wasn’t entirely forthcoming with us,” says Blake. “We were sort of in a bit of position where we were relying on them for the accuracy of what they were telling us.” Since then, Spaceflight has implemented a few changes, he says. The company now requires more evidence that licenses have been obtained, both from the customer and from the necessary government agency.

“It has been a pretty big coordination effort.”

But despite that hiccup, Spaceflight has forged ahead and is picking up more customers. In June the company announced that it is partnering with two fledgling launch providers, Rocket Lab and Virgin Orbit, to send more small satellites to space on future missions in late 2018 and 2019. If all goes well, the company will help launch up to 97 satellites before the end of this year, and it already has 10 missions scheduled for 2019.

Meanwhile, most of the spacecraft for the upcoming Falcon 9 launch have already been attached to the payload stack at Spaceflight’s facility in Auburn, Washington. Spaceflight says it has been responsible for the engineering, mission planning, regulatory processes, contracting and more for the flight. “It has been a pretty big coordination effort, but we have people who are really really good at that, both coordinating with customers, coordinating with SpaceX, and coordinating with the other vendors,” says Blake. “I think it’s been a really remarkable job of tracking all that and making sure that it’s all coming together at the right time.”