I have vivid memories of Ranger 7 impacting the moon, though I could not watch any of it. In the summer of 1964, living with my family on Kwajalein, Marshall Islands, I stayed up past midnight hunched by my radio, tape recording the live broadcast of the probe’s last minutes. Ranger 7 hurtled ever closer to Luna, sending back images second by second as it plowed toward destruction. I could hear the tweedle-tweedle of the carrier signal; when it abruptly stopped, Mission Control erupted into cheers. The spacecraft had slammed into the moon as planned.
It was one of those treasured moments when I felt connected to the greater world. We had no televisions on Kwaj, an American missile base about halfway between Hawaii and Australia. Sometimes at night I could pick up powerful radio stations including KSL in Salt Lake City and Radio Hanoi. But our radio station, AFRS Kwajalein, rarely linked for direct broadcasts from the States. This was a rare exception when I could hear a great adventure unfold as it was happening.
It wasn’t radio but the Internet that let me tune in to the launch of the LCROSS and LRO space probes on Thursday. There was a wonderful immediacy, as I lay on my bed with my laptop propped on a bent leg, enjoying NASA TV’s live coverage.
The Lunar Reconnaissance Orbiter (LRO) and Lunar CRater Observation and Sensing Spacecraft (LCROSS) were the payload aboard an Atlas V rocket with a Centaur as the top stage. Soon after launch the probes were to separate.
When the LRO reaches the lunar vicinity on Tuesday, it will loop into orbit and eventually begin a mapping program designed to find future astronaut landing sites.
LCROSS will go into Earth orbit around the poles, giving it the correct angle for a tremendous impact when it hits the moon in early October. The Centaur stage will plow in first, while LCROSS photographs the plume of dust kicked up by the impact. These readings will help characterize the moon’s makeup in a dark crater where the sun doesn’t shine, which should determine whether ice exists there — ice that might provided water for a lunar base. Four minutes later, LCROSS itself will smash into the moon, allowing telescopic examination of the second plume.
On the tiny image that NASA TV streams into cyberspace, the Atlas-Centaur stands on the launchpad, lazy puffs of gas emerging near the stage connection. This is Cape Canaveral Air Force Station, Fla., and behind the missile and the four lightning masts, the Atlantic stretches pale and hazy. The rocket is impressive, with a nearby forest reaching only about a third as tall.
At T minus five minutes, a series of commands comes over the speakers, including “Prepare water system.” Then a minute later, Atlas Launch Control announces that a scheduled 20-minute hold is starting. During the hold project managers must decide what to do about an approaching thunderstorm: go as planned, wait for a launch window a few minutes later, wait another few, or put it off until Friday.
A large bird that may be a bald eagle flaps into view briefly. Meanwhile, two weather balloons have been released, launch control says, though we don’t see them on the screen.
There are “thunderstorm conditions” at the cape, the launch officer adds. “We’ll be targeting the third opportunity now, at 5:32 p.m.,” which is 3:32 p.m. MST.
“The third opportunity is the only chance we’ll have today. … If we can’t, we’ll come back tomorrow. The weather forecast is better for Friday than today.”
Midway through the hold, launch weather officer Clay Flinn projects that “we will go green on the weather in just about ten minutes,” says launch control.
NASA launch director Chuck Dovale polls all the launch facilities. It’s the “final launch readiness poll,” he says. Heads of teams responsible for different operations all report “go” or “ready” except for one concerning the LRO. That team takes another minute, then, “LRO’s go for launch.”
Another poll is called just over a minute before the launch, and again, everything is go. NASA TV shows a majestic video of gas venting from the rocket under a cloudy sky. The spacecrafts’ internal power supplies take over, “and both are configured for launch,” says launch control. Meanwhile, last-minute status checks are continuing on features including “Centaur engine chill,” “airborne electrical,” “ground electrical,” and range weather. All respond “go,” in the voices of both genders
A close-up of the billowing gas is followed by a wider shot of the rocket, then the inside of the control room where wall screens show various angles of the launchpad. By now computers have assumed control of the sequence. “Launch enabled,” says a woman. A man begins the familiar litany of a countdown in five-second intervals, and then the last ten seconds are intoned.
Smoke and flashes at the base of the Atlas, the roar of main ignition, “and liftoff of the Atlas V rocket with LOR and LCROSS,” says launch control.
[Thursday’s launch. Photo credit, United Launch Alliance/Pat Corkery]
Then he says something that sends chills of pride and excitement down my spine, the way I felt 45 years ago with Ranger 7: This is “America’s first step on a lasting return to the moon.”