It started as a winter break. It ended with a doomed moon mission.

A group of students from Carnegie Mellon University in Pittsburgh traveled to Florida during their winter break last month.

The students, many of whom were training to be engineers and scientists, went there to attend a rocket launch that would send a small, 5-pound robotic rover they helped build on its journey to the moon. Then they hoped to have time for some sun and fun, renting a large house just three blocks from the beach.

Their trip did not go as planned.

“We never saw the beach,” said Nikolai Stefanov, a senior studying physics and computer science.

The rover, named Iris, took off on schedule for the moon during a perfect opening flight of Vulcan, a brand new rocket. But the spacecraft carrying the rover malfunctioned shortly after launch, and the students turned their rental house into a makeshift mission control as they improvised how to make the most of the rover's doomed journey.

“We had a mission,” says Connor Colombo, Iris' chief engineer. 'It wasn't the mission we thought. And maybe that made it more interesting because we had to do a lot of thinking, and I'm very grateful that I had that.

The Vulcan rocket, built by United Launch Alliance, lifted off on January 8. On board this rocket was Peregrine, a commercial lunar lander built by Astrobotic Technology of Pittsburgh. It was the first American spacecraft in more than fifty years to be launched with the aim of landing gently on the moon's surface.

And on board Peregrine was Iris, about the size of a shoebox, designed and built by Carnegie Mellon students. It was one of the payloads on this robotic mission; Astrobotic's main customer was NASA, which sent several experiments as part of preparations to send astronauts back to the moon in the coming years.

For the students, the trip to Florida was intended as an entertaining break during winter break to celebrate that, after years of effort and waiting, Iris finally went into space.

“We had filled our itinerary for the trip with other fun things,” said Carmyn Talento, a senior who served as the Iris mission team leader.

Iris started in 2018 as a student of Red Whittaker, professor of robotics at Carnegie Mellon. He gave the students an assignment: Put a small rover on the moon.

Dr. Whittaker was one of the founders of Astrobotic ten years earlier as a participant in the Google Lunar None of the competitors even reached the launch pad before the competition ended in 2018.

Astrobotic is now one of many companies that believe there will be profits to be made from providing a delivery service to the moon. (Another of these companies, Houston-based Intuitive Machines, aims to launch its spacecraft to the moon next week.) Dr. Whittaker saw that these commercial ventures offered the opportunity for low-cost lunar missions like the one he asked his students to devise. .

Although Dr. Whittaker is no longer directly involved with Astrobotic, he spoke with company officials about the size, weight and limitations of what could fit on Peregrine. That made the rover a real engineering problem for his class.

“I actually knew the height above the ground for the attachment and therefore the release and how far it should float to the ground,” said Dr. Whittaker. “And so it would be possible to calculate the energy of the impact and the dynamics associated with landing in a stable position or overturning if it hits the wrong rock.”

Successive classes of students conceived and revised the design and then built and tested the rover. Other students also participated, training to work in mission control or take on other duties.

After a series of delays, the Vulcan rocket finally reached the launch pad in January.

Some Carnegie Mellon students flew to Florida. Others traveled by van, driving nearly 1,000 miles south of Pittsburgh. Several former students who had worked on the rover and had since graduated also made the pilgrimage. (Mr. Colombo, the lead engineer, graduated in 2021 and now works at Astrobotic.)

They would stay at the holiday home for four days in case the launch was delayed by bad weather or technical problems.

The difficult, high-pressure part of their mission — turning on the rover, deploying it to the surface and driving it around before the battery's energy ran out in two to three days — should still have been in the future, after Peregrine landed in February. 23 on the near side of the moon at a spot known as Sinus Viscositatis, or Bay of Stickiness.

By then, winter break would be over and they would be back at Carnegie Mellon, combining their spring classes with a stay at a mission control facility the university had built for this and future space missions.

The Vulcan rocket took off without incident. Less than an hour later, Peregrine separated from the rocket's upper stage, bound for the moon.

But shortly afterwards, Astrobotic announced on X that “an anomaly had occurred.” Later in the day, the company said: “We are currently assessing what alternative mission profiles may be feasible at this time.”

Astrobotic engineers believe that a faulty valve failed to close completely, leading to the rupture of one of the spacecraft's tanks. With propellant leaking into space, the possibility of Peregrine landing on the moon was gone.

“Then the question became, 'Okay, what can we do now?'” said Mr. Stefanov, who led the rover's mission control. “We weren't worried at all. I think in some ways we were excited.

In the rental house: “We separated and separated parts of the house to point out certain things,” Mx. Talento said. “We had a table in the living room, kind of our main work station, where we had several laptops, and we moved a TV from another room to serve as a monitor. That was kind of the main control room of the mission.”

There were up to 30 people in the house, Mx. Talento said.

For security reasons, people in Florida could not access the spacecraft systems directly via the Internet. Instead, a skeleton crew at Carnegie Mellon served as a go-between, carrying messages between the Peregrine spacecraft managers at Astrobotic's headquarters in Pittsburgh and the beach house.

“Somehow it worked,” Mr. Colombo said.

A few days into the mission, Astrobotic began supplying power to the payloads such as Iris. Raewyn Duvall, a graduate student in electrical and computer engineering who was a program manager for Iris, remembers looking at the video monitor when telemetry started coming from the rover. “They didn't tell us at the time that they had us excited, so it was an unexpected heartbeat,” Ms. Duvall said.

The Iris team then began turning on systems on the rover, such as the computer and two-way communications, that were originally not supposed to be turned on until after arriving on the moon.

When the beach house rental ended, the students headed back to Pittsburgh for the remainder of the mission. And on January 18, it was over.

Peregrine's trajectory was designed to orbit the Earth once before returning to rendezvous with the moon. But the propellant leak had put the spacecraft on a collision course with Earth. Due to the damaged condition of the propulsion system, NASA convinced Astrobotic that the best approach was to simply re-enter the atmosphere and burn up.

There will be no new Iris, but other moon missions will be built with contributions from Carnegie Mellon students. One is MoonRanger, a rover that is slightly larger, about the size of a suitcase and weighs seven pounds. It will look for signs of water near the moon's south pole.

And this spring there will be another space robotics course at Carnegie Mellon. “So we know there's a group of people working on the next one,” Ms. Duvall said.