Provided by NASA, this is an image taken shortly after the Centaur rocket hit the moon Friday morning. The impact did not produce the dramatic flash which many had been led to believe would be visible from Earth.

AP

“We jumped up and down. There was no turning back. We were on a collision course.”

That was how veteran planetary scientist Peter Schultz of Brown University described the excitement Friday morning at NASA’s Ames Laboratory in California as he and colleagues watched the suicide dive of an impactor and its mothership into a crater near the south pole of the moon in a violent bid to find water.

“You could see the moon getting closer and closer,” Schultz said. He spoke from the headquarters for the team operating the Lunar Crater Observation and Sensing Satellite, or LCROSS. Schultz is a member of the team.

The intent was to have the impactor, an empty Centaur booster rocket, blast out a plume of debris that the mothership would photograph and analyze before taking its own kamikaze plunge into the shadowed crater Cabeus four minutes later. It was thought that the crater’s steep walls, a mere 60 miles from the south pole, might have allowed water ice to survive the blazing heat of the sun over the eons.

But the impact did not produce the dramatic flash and the prominent cloud of ejecta which many had been led to believe would be visible from Earth.

That wasn’t in the cards, Schultz said.

“If you were looking with a big telescope, you would be lucky if you could see a stadium-sized crater,” he said. “In other words, you might be able see down to about 100 yards. This was a fifth of that. OK, we were sitting on Earth trying to see something five times smaller than a football field. All we would have seen is a smudge at best. It all went according to plan.”

Schultz said there were raised expectations among the public. “The press was saying we were going to bomb the moon. That was press hype, not NASA hype.” He paused and chuckled. “What we did was, we ran into the moon.”

He declined to speculate on preliminary findings.

“The devil is in the details,” he said. “Water is something we find everywhere. We need to be very careful to calibrate these measurements. If we make a small error, it could look like a lot more, or a lot less. Now, it’s time to get some sleep, to look at the data with fresh eyes. We’ll be going like gangbusters over the next few days.”

The smashup took place at 7:31 a.m. EDT.

“If there’s water there, or anything else interesting, we’ll find it,” Tony Colaprete, the mission’s chief investigator, said in a news release.

Besides water, spectrometers aboard the mothership were to look for fragments of water molecules, salts, clays, hydrated minerals and various organic materials. The information gathered was radioed back to Ames for analysis.

The force of the Centaur impactor was estimated to equal 1.5 tons of TNT, according to the Associated Press, and had been expected to carve out a crater inside Cabeus the size of an Olympic swimming pool.

NASA predicted on Monday that the column of debris hurled aloft could reach six miles.

Because of the time of day, the flash and the blasted-out material, however prominent, would not have been visible to anyone in Rhode Island. The impact was best seen from west of the Mississippi River, with Hawaii occupying the catbird seat.

Water is important for manned missions to the moon. The Web site Spaceweather.com estimated that it costs $30,000 to lift a quart of water to the moon. A water source on the moon could also provide oxygen and rocket fuel.

Brendan Hermalyn, a graduate student in planetary science who is working with Schultz on the project, stayed up all night to monitor the mission.

Hermalyn said he and others were looking primarily at telemetry, in addition to onboard cameras, as the crash neared.

“That is the neatest view,” he reported. “The best part was when we were looking at the impact as the camera angle was changing.”

He said the watchers were able to detect a flash as the Centaur hit.

In California, the big double crash came at 4:31 a.m.

Was he tired?

“You can run on the adrenaline,” he said. “We’re probably going to take a little rest, then the science team is going to discuss the preliminary results.”

tmorgan@projo.com