The United Launch Alliance (ULA) is gearing up for an important milestone this week with the second flight of its Vulcan Centaur rocket. This upcoming mission not only aims to transport an inert payload into orbit but also includes several experiments and demonstrations. Importantly, it will serve as a significant step in completing Vulcan's certification process with the U.S. Space Force (USSF).

Simultaneously, SpaceX has encountered some setbacks this week due to an off-nominal deorbit burn of a Falcon 9 second stage which followed the Crew-9 mission. This particular stage landed in the South Pacific Ocean, albeit outside the defined reentry corridor. As a result, while investigations are underway, the company has postponed Monday's planned OneWeb mission launch from Vandenberg to next week. However, a Starlink mission is now scheduled to take place at Cape Canaveral this Saturday, October 5.

In addition to Vulcan's preparations, a Falcon 9 rocket is being readied to launch the Hera mission for the European Space Agency (ESA) from Florida. Hera will carry two cubesats that focus on studying outcomes from NASA's Double Asteroid Redirection Test (DART), which impacted the Dimorphos asteroid two years ago. Launch Complex 39A (LC-39A) remains configured for the forthcoming Europa Clipper mission, which is set to fly on a Falcon Heavy next week. Both interplanetary missions have launch windows extending until the end of the month to accommodate any further delays.

Overview of Vulcan Centaur

The Vulcan Centaur is a heavy-lift rocket designed explicitly for the National Security Space Launch (NSSL) program. It utilizes advanced technologies developed from ULA's historical Atlas V and Delta IV rockets, incorporating a modular design around a common booster core. The rocket consists of a wider 5.4 m core featuring an internal orthogrid aluminum structure. Unlike previous models, Vulcan burns liquid methane and oxygen using two BE-4 engines.

To enhance lift capabilities during the initial ascent, two Graphite Epoxy Motor (GEM) 63XL solid rocket boosters (SRBs) support the main engines. These boosters utilize their solid propellant for about 90 seconds before they are jettisoned. After stage separation, dual RL10C-1-1A engines take over to propel the Centaur V upper stage before entering a coast phase. Finally, these engines will reignite, guiding the vehicle into a hyperbolic injection orbit around the Sun.

Looking ahead, two USSF missions are slated to launch on Vulcan before the end of the year, contingent on the successful completion of Cert-2 flights and subsequent certification approvals. The first mission, USSF-106, will be notable as it will employ the VC4S configuration, utilizing four GEM 63XL SRBs. Following that, the USSF-87 Mission is expected to carry the GSSAP-7 and 8 satellites directly into a geosynchronous orbit. This pair of Geosynchronous Space Situational Awareness satellites is part of the USSF's larger plan to establish a Space Base Situational Awareness (SBSS) constellation for monitoring space traffic and debris in Earth's orbit. Further missions are lined up for 2025, encompassing launches of Block III satellites destined for the Global Positioning System (GPS) constellation and Vulcan's inaugural launches from SLC-3E in Vandenberg.

Hera Mission Details

The Hera mission is scheduled for liftoff from SLC-40 at the Cape Canaveral Space Force Station (CCSFS) on Monday, October 7, at 10:52 AM EDT (14:52 UTC). While the specific booster supporting Hera has yet to be determined, it will be expended after this flight.

Developed by the ESA, the Hera mission is set to provide vital data for the international Asteroid Impact and Deflection Assessment (AIDA). Once launched, the Hera spacecraft will journey through space for approximately two years, ultimately reaching Dimorphos, while conducting a Mars flyby during its transit to the binary system. The spacecraft is outfitted with twin three-panel solar arrays stretching five meters each.

Hera's scientific objectives include a detailed investigation of Dimorphos, focusing on characterizing its mass, composition, the size of DART's crater, and assessing the momentum transfer efficiency resulting from the impact. The spacecraft is equipped with a 1.3 m high-gain antenna alongside two omnidirectional low-gain antennas, supplemented by deep space transponders for communication purposes.

As Hera approaches Dimorphos, it will navigate through a cloud of debris caused by the prior impact, employing onboard framing cameras and image processing for autonomous navigation. A PALT laser range finder will facilitate distance measurements through laser pulse reflections. Additionally, a thermal infrared imager will allow for surface mapping, while the Hypercount H hyperspectral imager is set to conduct surveys and prospect the asteroid.

Hera also carries two 6U cubesats, which will be released once near Dimorphos. The Milani cubesat will map the asteroid's surface and analyze the composition of the surrounding dust clouds. Conversely, the Juventus cubesat plans to deploy a radar antenna and land on Dimorphos, aiming to measure gravity fields, surface properties, and the interior geophysical structure. By the conclusion of the Hera mission, Dimorphos is anticipated to become the most thoroughly studied asteroid within our solar system.

FAQs

What is the purpose of the Vulcan Centaur rocket?The Vulcan Centaur rocket is primarily designed to meet the requirements of national security space launches and supports various missions including commercial and interplanetary explorations.

When is the Hera mission scheduled to launch?The Hera mission is set to launch on October 7, 2024, from Cape Canaveral Space Force Station.

What are the main scientific goals of the Hera mission?Hera aims to investigate the asteroid Dimorphos, focusing on its mass, composition, and the results of the DART impact.

What technology does the Vulcan Centaur utilize?Vulcan employs a two-stage design with BE-4 engines burning liquid methane and oxygen, and it utilizes solid rocket boosters for enhanced initial thrust.

What will happen to the 6U cubesats onboard Hera?The cubesats, Milani and Juventus, will be deployed once the spacecraft reaches the vicinity of Dimorphos, conducting surface mapping and analysis.