The Vulcan Centaur rocket — due to launch in late 2023 — is a new methane-fueled rocket from one of America's most experienced space launch operators, United Launch Alliance (ULA). The Vulcan Centaur rocket will join ULA's well-established workhorses Atlas V and Delta IV in launching payloads into space.
As with its predecessors, this will be able to launch satellites into a variety of orbits, including geosynchronous ones, for NASA and other U.S. government customers. But it's hoped that the new rocket will be able to do this more cheaply, thanks to an initiative the company refers to as SMART — for "Sensible, Modular, Autonomous Return Technology". This allows the most expensive parts of the rocket to be recovered after launch and refurbished for reuse.
Parts of the new design use well-established technology, such as the Centaur upper stage and the same type of solid rocket boosters as Delta IV. More innovative is the main Vulcan core stage, which will employ a completely different type of rocket engine to previous ULA launchers. This is the BE-4, designed and manufactured by Jeff Bezos's Blue Origin company.
Andrew May holds a Ph.D. in astrophysics from Manchester University, U.K. For 30 years, he worked in the academic, government and private sectors, before becoming a science writer.
Blue Origin BE-4
Unfortunately, the BE-4 engine has proved to be one of the main stumbling blocks on Vulcan Centaur's journey to flight readiness, which was originally expected in 2020. One reason the BE-4's development is progressing slower than planned is that it's a hugely ambitious piece of engineering.
More powerful than the Space Shuttle's main engines, it's designed to be fueled by methane, which is a brand new fuel in the context of space launch systems. Several companies — prominently SpaceX as well as Blue Origin — are developing launchers around it, but the fact remains that to date no methane-fueled rocket has made it into space, according to NASA Space Flight (opens in new tab). Nevertheless, it's hoped that Vulcan Centaur will change that before the end of this year.(opens in new tab)
Who will use the Vulcan Centaur?
One of Vulcan Centaur's biggest users will, of course, be the American space agency NASA. But another important customer, albeit one that keeps a lower profile, is the U.S. Space Force (USSF). Established at the end of 2019, this is a separate branch of the U.S. armed services alongside the Army, Navy, Air Force and Marine Corps.
Prompted by the recognition that space — particularly in the form of surveillance and communication systems — has become indispensable to modern military operations, it's the role of the USSF to protect American interests in the space domain.
Where in the past military space launches were the province of the U.S. Air Force, they now fall within the remit of the USSF. As an example, in July 2022 a ULA Atlas V rocket launched a pair of spacecraft — a missile-tracking satellite and a technology demonstrator platform — on behalf of the USSF.(opens in new tab)
Centaur upper stage
Unlike the methane-fueled, partially reusable Vulcan booster, there's nothing revolutionary about Vulcan Centaur's upper stage. In its basic design, Centaur is one of America's oldest and most successful pieces of space hardware.
Originally conceived at the very dawn of the space age in the late 1950s, its first successful flight, atop an Atlas booster, took place on 27 November 1963. Since then, Centaur has flown over 260 times, sending one spacecraft after another on its way into the history books — from America's first lunar soft lander, Surveyor 1, back in 1966 to the Curiosity and Perseverance Mars rovers of today.
To keep track of the Vulcan Centaur launch progress, you can visit ULA's Vulcan Countdown page (opens in new tab). Additionally, to learn more about the rocket's statistics, see this Vulcan Centaur design illustration (opens in new tab).
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