"People going up to the Moon is kind of cool," eight-year-old Isiah says.

He is one of an estimated 400,000 spectators expected to line the causeways, beaches and motel balconies along Florida’s Space Coast for Wednesday’s Artemis II launch attempt at 18:24 local time (23:24 BST).

They will watch as four astronauts lift off on a mission designed to carry them around the Moon, potentially taking them farther from Earth than any humans before.

The 10-day test flight by Nasa will not include a lunar landing. However, the crew could observe views of the Moon’s surface never previously seen directly by astronauts.

Amanda Garcia, who traveled more than 1,000 miles from New Mexico, is among those gathered for the event. "I'm pretty excited about it," she tells us.

"I came out here to see it, and I heard it's gonna be a great show. A lot of people are going to be here."

Across Titusville and Cocoa Beach, beyond the Kennedy Space Center, businesses are preparing for the surge. Bars are promoting themed “moonshots,” while hotels caution guests about significant delays reaching viewing areas.

Officials describe a “historic influx” of visitors, estimating an economic boost of about $160m (£121m). Traffic plans have been put in place as illuminated highways, launch towers and rows of camper vans set the stage for the evening.

Near the launch pads, Brenda Mulberry has been selling Nasa-themed merchandise for four decades. From her Merritt Island shop, Space Shirts, she offers racks of colorful T-shirts featuring rockets, mission patches and lunar imagery.

Regular launches draw steady business, but this one stands apart, she says. "We've wanted to go back to the Moon since the '70s. People are excited. People are beyond excited," she said.

Brenda has stocked up in anticipation of what she expects will be her largest crowd yet.

"I want to have the first T-shirt shop on the Moon," she says. "Because if you've been there, you get the T-shirt, right?" she adds, laughing.

Future Artemis missions aim to return humans to the Moon for the first time since 1972, with plans to establish a long-term base to utilize resources and support eventual missions to Mars.

Mission commander Reid Wiseman said he hopes the program will inspire younger generations.

"In our lifetime, we've looked at the Moon knowing that people had been there. And now in the Artemis generation, kids will walk out and look at the Moon going, we are there. We are there now, and we are going further into our solar system."

Attention will focus on Launch Pad 39B, the historic site used during the Apollo program’s first Moon landing in 1969. Positioned there is Nasa’s Space Launch System rocket.

Standing 98m (321ft) tall, the rocket is the most powerful ever launched by the agency. At its top is the Orion capsule, roughly the size of a small van, where the four astronauts will spend 10 days together. This will mark the first crewed test of the spacecraft.

If conditions allow, liftoff is scheduled within a two-hour window between 18:24 and 20:24 local time (23:24–01:24 BST). The astronauts will board Orion about four hours beforehand, following years of joint training.

Wiseman will command from the left seat, with pilot Victor Glover beside him. Behind them sit Christina Koch and Canadian astronaut Jeremy Hansen, who will be making his first trip into space.

Once in orbit, Orion will spend its first day in high Earth orbit conducting system checks, including manual flight tests and life-support evaluations, before setting course for the Moon.

On the second day, a powerful burn will send the spacecraft onto a free-return trajectory, looping it around the Moon and back toward Earth, with minor adjustments along the way. Each day will bring new tests and operational tasks.

Day six is expected to be particularly significant, as Orion passes behind the Moon. Communications will be lost for about 40 minutes, leaving mission control without contact during that period.

The spacecraft will travel roughly 4,000 to 6,000 miles above the lunar surface and could exceed the Apollo 13 record distance of about 250,000 miles (400,000km) from Earth, depending on its path.

In the following days, the capsule will naturally arc back toward Earth, guided by the same trajectory, with small corrections ensuring a precise re-entry angle.

The final phase will involve re-entry at speeds of about 25,000mph (40,000 km/h), subjecting Orion’s heat shield to extreme temperatures capable of charring rock.

After the uncrewed Artemis I mission, engineers identified cracking and debris loss in the heat shield during a two-step “skip” re-entry maneuver. That process briefly lifted the capsule before its final descent to manage heat and forces.

For Artemis II, the same technique will be used, but with adjustments to angle and timing to reduce stress on the spacecraft. This mission will be the first time the revised approach is tested with astronauts on board.

If successful, Artemis II will mark another step toward returning humans to the Moon, setting the stage for future landings more than 50 years after the last.

And along the Space Coast, amid marshland and launch sites, at least one spectator will likely be wearing one of Brenda Mulberry’s shirts—already imagining the day her designs appear not just on Earth, but in a photograph taken from the Moon.