First Vulcan/Centaur launches Peregrine Moon Lander

Photos credit Dennis Hlavsa and Sarah Howard

   ULA’s new rocket is the long-planned replacement for the current versions of Atlas and Delta vehicles. The Vulcan booster, 109’ long and 17’ wide, features two Blue Origin BE-4 engines, powered by methane and liquid oxygen (methalox). Attached to the stage are two GEM-63XL
solid rocket boosters. Combined, thrust at liftoff is 2 million pounds.
The upgraded Centaur second stage features twin Rocketdyne RL106-11 engines, powered by liquid hydrogen and liquid oxygen (hydrolox). Topping off the 202’ tall rocket, a fairing encloses the Peregrine moon lander.
   Astrobotic’s Peregrine is the first private lunar mission. Upon landing, it is a platform which will remain stationary, outfitted with twenty payloads. Five are supplied by NASA’s Commercial Lunar Payload Services. A device known as LRA, comprised of reflective glass prisms, will act
as precise marker of the lander’s position via lasers. Other experiments will measure lunar radiation and volatiles. A college-designed surface rover is among the remaining cargo. Celestis has two capsules riding aboard the rocket. Enterprise will remain attached to the Centaur stage then be propelled into deep space. It includes 265 ash containers with Star Trek actors and other space notables. Attached to the Peregrine lander, Tranquility Flight features additional cremated remains. Vulcan arrived at Cape Canaveral Space Force Station late in 2022 then began a test campaign leading to a static fire in March. Soon after, an issue arose with the upgraded Centaur design, causing the launch to slip to December.

   A wet dress rehearsal revealed additional remedies to address; a second wet dress rehearsal was required. Peregrine arrived in Florida on October 31 st for final processing at Astrotech. Vulcan/Centaur was prepared in a pad-adjacent hanger known as the VPF, then received its twin solid motors and fairing-encapsulated payload. 

Photos credit John Howard

   The stack was rolled out January 5 th via its Transporter, arriving 1800 feet later atop the hardstand on Pad 41.
The countdown began Sunday afternoon, January 7 th in preparation for the overnight launch. Significant milestones included fueling, completed by midnight. Five seconds before liftoff, the BE-4 engines ignited, then GEMs propelled the rocket skyward, heading to a 30-degree
inclination as the 220,000-mile journey to the moon began. Max Q in which the vehicle incurs the greatest aerodynamic stresses, passed at T+1:16. Twin SRB’s separated at 1:50 into flight.
    The Vulcan stage continued to climb powered for nearly five minutes before main engine cut-off and separation. Ten seconds later, Centaur ignited its engines, burning for nearly ten minutes. As the second stage continued to propel the payload, the fairings which protect Peregrine during atmospheric ascent, split in two then peeled away from the rocket.
   At 15 minutes after launch, the Centaur stage shut down to enter a coast phase. A second ignition lasting four minutes occurred at 43 minutes past liftoff. Seven minutes later, Peregrine separated from the Centaur into a trans-lunar injection orbit in preparation for a planned Feb 23 rd
landing at Sinus Viscositatis (bay of stickiness). However, teams at Astrobotic were evaluating an anomaly which prevented Peregrine from achieving a stable, sun-pointed orientation. Without the proper alignment for the craft’s solar arrays, insufficient power may affect the moon
mission’s goals. Centaur, carrying the Celestis Enterprise payload, burned one more time an hour and 18 minutes after liftoff, propelling the stage to deep space.

By John Howard