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Tuesday, January 9, 2024

Vulcan Centaur Has A Great First Flight While Peregrine Fails

Success and setbacks by Jeff Foust Monday, January 8, 2024 Bookmark and Share The first launch of a new rocket is a risky endeavor, with historical success rates on the order of 50%. Last year, for example, saw the first flights of ABL Space Systems’ RS1 and Relativity Space’s Terran 1 fail to reach orbit; the first integrated test flight of SpaceX’s Starship failed spectacularly as well. Lunar landers are also risky, with a historical success rate of less than 50%. Last year India succeeded with its Chandrayaan-3 lander but Japanese company ispace failed with its HAKUTO-R M1 mission. We’re at a point now where we need to fly,” said ULA’s Wentz. Combining the two—launching a lunar lander on the first flight of a new rocket—would then seem to be really pushing one’s luck. But that was the case Friday at Space Launch Complex 41 at Cape Canaveral, as United Launch Alliance’s Vulcan Centaur, carrying Astrobotic’s Peregrine lunar lander, rolled out to the pad. The two needed each other. ULA was looking for customers for its first two flights willing to accept the higher risk of launching on a new rocket (presumably at a discount) so that it could win certification from the US Space Force for launching high-value national security payloads. Astrobotic was one such customer, a startup willing to take on that higher risk of being on the first flight of a new rocket. (See “The year new launch vehicles finally lift off”, The Space Review, January 2, 2024.) “We do feel confident with ULA. They’ve been great partners,” said John Thornton, CEO of Astrobotic, in an interview the day Vulcan rolled out to the pad for launch. “I think they’re going to do very well on this mission.” He said he felt more nervous about landing: “That’s totally on us. Launch is more of a partnership.” ULA executives went into the launch expressing confidence. “We’re at a point now where we need to fly,” said Gary Wentz, vice president of government and commercial programs at ULA, during a briefing Friday. The company was eager to demonstrate the performance of the new rocket and start working through a backlog of more than 70 missions, including 38 for Amazon’s Project Kuiper constellation and about two dozen for the Space Force. ULA argued that while Vulcan was a new rocket, it leveraged extensively heritage from the Atlas and Delta rockets. “Many of the systems that we’re flying here actually have a fair amount of flight experience under their belts,” said Mark Peller, vice president of Vulcan development at ULA. “We’ve had a very rigorous qualification program.” Many of the new components, executives said, had already flown in one configuration or another on Atlas and Delta. “As we brought Vulcan on board and designed the systems, we leveraged the existing systems as much as possible,” said Wentz. “The only hardware that hasn’t flown prior to this flight is the BE-4 engine.” Still, the expectation was that, on the first launch attempt of a new rocket, something would go wrong during the countdown, leading to a delay or a scrub. For Monday’s launch, orbital mechanics for placing Peregrine on a highly elliptical orbit with an apogee of 360,000 kilometers allowed for a 45-minute launch window. There were launch opportunities the next three days, but all had windows of less than ten minutes, and in one case just one minute. After January 12, ULA and Astrobotic would have to wait until January 23. As Sunday night turned into Monday morning for the first launch, scheduled for 2:18 am EST, nothing had gone wrong. After rains over the weekend, skies had cleared. The countdown was proceeding smoothly, with no technical issues reported. Tory Bruno, CEO and president of ULA, later remarked that there was so little chatter among controllers working issues “I thought my headset was broken.” As the countdown exited its final preplanned hold at T-7 minutes, anticipation grew. Surely, many thought, there would be a “Hold! Hold! Hold!” called on the countdown net in those final minutes, as some issue—maybe with those new BE-4 engines, maybe with something else—cropped up. There would be a letdown, but a knowing sigh: it’s a new rocket, after all, things are going to go wrong the first time. Yet, there was no hold called, no letdowns, and no sighs. At the countdown hit zero, the two BE-4 engines from Blue Origin ignited, as did the two GEM 63XL solid rocket boosters from Northrop Grumman. After ten years of development, and years of schedule slips, Vulcan had finally lifted off. Bruno, appearing on NASA TV a few minutes after separation, was asked how he was feeling. “Yeehaw!” he responded. The next 50 minutes went like clockwork. Those solid rocket boosters did their job and separated nearly two minutes into the mission. The booster, its methane-fueled BE-4 engines producing a distinctive blue plume, continued for another three minutes before separating. The Centaur upper stage, powered by two venerable RL10 engines, went to work, performing a ten-minute burn followed, nearly a half-hour later, by a four-minute burn. About 50 minutes and 30 seconds after liftoff, the Peregrine lander separated from the Centaur. Bruno, appearing on NASA TV a few minutes after separation, was asked how he was feeling. “Yeehaw!” he responded. “I am so thrilled, I can’t tell you how much.” While Peregrine was on its way to the Moon, the mission was not over for ULA. The company continued tests of the Centaur for another three and a half hours, including a third burn of the RL10 engines to place it into a heliocentric orbit. A small payload from Celestis, the space memorial company, remained attached to the stage as planned. “We’ll use this opportunity of this flight test to validate a lot of our future mission objectives,” Wentz said before the launch, simulating an extended-duration mission for Centaur like that needed for injecting payloads directly into geostationary orbit. “This demonstration will capture thermal data. It will enable us to anchor our models for extended-duration coast.” Bruno later said there was only one issue during the mission. “And it was pretty serious: the coffee maker in Launch Control broke down!” he posted on social media. “Fortunately Alex, one of our Rocket Scientists, sprang into action and solved it in real time, allowing us to continue with the count.” Peregrine The Peregrine lunar lander shortly before it was encapsulated in the Vulcan payload fairing. (credit: ULA) Peregrine peril All eyes now turned to Astrobotic and its Peregrine lander. The spacecraft carried 20 payloads, including five NASA instruments through the agency’s Commercial Lunar Payload Services (CLPS) program, an award valued at $108 million. Other customers ranged from the Mexican space agency AEM, which was flying five micro-rovers, to two companies, BitMEX and BTC, flying payloads linked to the cryptocurrency bitcoin (taking bitcoin, literally, to the Moon.) Two of those payloads caused a last-minute controversy. Celestis and Space Elysium each included small capsules containing cremated remains. That prompted a protest from Navajo Nation, whose president, Buu Nygren, sent a letter to NASA and the Department of Transportation in December objecting to the inclusion of those remains. “The placement of human remains on the moon is a profound desecration of this celestial body revered by our people,” he said. “We know we’re headed into a gauntlet here. We know we’re headed into very difficult territory,” Thornton said before the launch. He pointed to a similar controversy a quarter-century ago, when NASA’s Lunar Prospector spacecraft carried cremains from Eugene Shoemaker, the late planetary scientist. At that time NASA vowed that it would consult with Navajo Nation on any future missions that might carry such payloads. However, Peregrine was not a NASA mission: it was a commercial mission carrying NASA and other payloads. “These are commercial missions. We don’t have the framework for telling them what they can and can’t fly,” said Chris Culbert, NASA CLPS program manager, at a briefing January 4. Astrobotic’s Thornton, at a prelaunch briefing Friday, expressed some frustration about the controversy. “We have tried to do the right thing at every turn along the way,” he said. “I’m disappointed that this conversation came up so late in the game. I would have liked to have had this conversation a long time ago.” Those payloads, he noted, were announced in 2015 and 2020. NASA did agree to participate in a “tribal consultation” about the payloads, said Joel Kearns, deputy associate administrator for exploration in NASA’s Science Mission Directorate. “An intergovernmental team is currently looking into this in more detail,” he said. That consultation took place at the White House on Friday, but did not result in removing the payloads. Peregrine, with its full complement of payloads, was now in its planned lunar transfer orbit after the successful launch early Monday. Controllers worked quickly to establish communications with the spacecraft, get it power-positive, and start checking out its various systems. Initially, that seemed to go well. “Peregrine powered on, acquired a signal with Earth and is now moving through space on its way to the Moon,” Thornton said in a statement about two hours after launch. Several hours later, though, Astrobotic reported something went wrong. “After successful propulsion systems activation, Peregrine entered a safe operational state. Unfortunately, an anomaly then occurred, which prevented Astrobotic from achieving a stable sun-pointing orientation,” the company said in a statement released about seven hours after liftoff. That statement did not disclose the nature of the anomaly, but subsequent ones pointed to the spacecraft’s propulsion system. The immediate concern was getting the spacecraft oriented so that its solar panels pointed towards the Sun, as the onboard batteries were reaching what the company called “operationally low levels.” An “improvised” maneuver to reorient the spacecraft worked, getting the spacecraft’s batteries charged. “The Mission Anomaly Board continues to evaluate the data we’re receiving and is assessing the status of what we believe to be the root of the anomaly: a failure within the propulsion system,” the company stated. It soon became clear that this propulsion anomaly would keep Peregrine from landing on the Moon. “Unfortunately, it appears the failure within the propulsion system is causing a critical loss of propellant. The team is working to try and stabilize this loss, but given the situation, we have prioritized maximizing the science and data we can capture,” the company said, noting it was looking at “alternative mission profiles.” “We knew going into this that it’s a really difficult thing to do when we decided to go down this path,” said Kearns, “and it might turn out that they’re not all going to be successful, particularly some of the very earliest ones.” The most recent update at the time this article was prepared for publication, about 12 hours after Astrobotic first reported the anomaly, confirmed that the propellant leak would keep Peregrine from attempting a landing. “An ongoing propellant leak is causing the spacecraft's Attitude Control System (ACS) thrusters to operate well beyond their expected service life cycles to keep the lander from an uncontrollable tumble. If the thrusters can continue to operate, we believe the spacecraft could continue in a stable sun pointing state for approximately 40 more hours, based on current fuel consumption,” it announced. “At this time, the goal is to get Peregrine as close to lunar distance as we can before it loses the ability to maintain its sun-pointing position and subsequently loses power,” the company concluded. The impending failure of Peregrine will be the first real test of NASA’s “shots on goal” philosophy for CLPS: just as not every shot makes it into the goal, not every lander will make it onto the lunar surface. Kearns, in an interview before the launch, said that NASA was still committed to that approach to CLPS. “I don’t see there being a retrenchment” in the event of mission failures, he said. “We knew going into this that it’s a really difficult thing to do when we decided to go down this path, and it might turn out that they’re not all going to be successful, particularly some of the very earliest ones.” “The companies, we believe, are in it for the long haul,” he added. “We think it’s the best path to get US industry to do this as a service.” “We know we’re headed into a gauntlet here. We know we’re headed into very difficult territory,” Thornton said before the launch. “At the end of the day, we need to get as much data as we can at every point through the mission so we can learn and get better as an industry.” “There are many challenges with spaceflight, and we’re incredibly proud of the Astrobotic and NASA teams that have put us one step closer to a robotic return to the lunar surface as part of Artemis,” Kearns said in a statement Monday after Astrobotic reported the anomaly. “NASA is committed to supporting our commercial vendors as they navigate the very difficult task of sending science and technology to the surface of the Moon.” While NASA remains committed to CLPS, it might delay the next mission with Astrobotic, which involves an even larger lander called Griffin and is currently scheduled for launch as soon as late this year. It will deliver to the south polar regions of the Moon a NASA rover called VIPER to look for volatiles. VIPER itself costs more than $430 million, while NASA is spending $320 million on the CLPS task order with Astrobotic: a very expensive shot on goal. As NASA and Astrobotic step back and review what went wrong, ULA is focused on what went right with Vulcan. It said before the launch, which the company called Cert-1, it could be ready as soon as April for its second launch, Cert-2. The timing will depend on the availability of the payload, Sierra Space’s Dream Chaser cargo spaceplane, and activity at the ISS to allow Dream Chaser to dock there. ULA’s Peller said before the launch that all the components for the Cert-2 Vulcan were coming together, including BE-4 engines going through acceptance testing at Blue Origin’s West Texas facility. “That’s all coming together to support delivery down here at the launch site and align with that timeline,” he said. If Cert-2 is successful, ULA expects to get its Space Force certification and start launching national security payloads as soon as this summer. ULA is projecting four such launches through the end of the year, although Wentz said the company expects “some movement in the manifest.” “It’s the future of our company,” Peller said of Vulcan. That future looks a little more secure after Cert-1, even as Peregrine serves as a reminder of the hazards of flying new spacecraft on new missions. Jeff Foust (jeff@thespacereview.com) is the editor and publisher of The Space Review, and a senior staff writer with SpaceNews. He also operates the Spacetoday.net web site. Views and opinions expressed in this article are those of the author alone. Note: we are using a new commenting system, which may require yo

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