Editorial observatory, continuously updated

How we verify information
EN
ES EN FR IT DE PT

Article

Next-generation rockets: what SLS, New Glenn and Ariane 6 reveal

An orbital rocket is not defined only by its height or engine count. Its stages, propellants and intended mission determine how it delivers a spacecraft or payload into space. NASA and ESA material supplied here places SLS, New Glenn and Ariane 6 in context without extending beyond published specifications.

By CosmoInsider editorial team Published 4 min
Next-generation rockets: what SLS, New Glenn and Ariane 6 reveal
Type: Image · real photograph Provider: NASA Image and Video Library Author: Don Pettit Credit: The last rays of an orbital sunset outline Earth’s horizon · Don Pettit · NASA Licence: NASA Media Usage Guidelines Colour treatment: original

Key facts

  • NASA says the SLS core stage uses four RS-25 engines and ICPS uses one RL10.
  • Each SLS solid booster burns about six tons of propellant per second, according to NASA.
  • NASA lists seven BE-4 engines, over 13 metric tons to GTO and 45 metric tons to LEO for New Glenn.
  • ESA identifies Vulcain 2.1 and P120C boosters in Ariane 6’s initial propulsion.

Related records

Launch vehicles turn engine thrust into the speed needed to place payloads on orbital trajectories or, in some cases, send them beyond Earth orbit. They do not all serve the same purpose. NASA presents the Space Launch System (SLS) as a US deep-space exploration rocket associated with Artemis lunar missions; New Glenn appears in NASA launch-services information; and the European Space Agency (ESA) describes Ariane 6. A sound comparison must separate the published facts from conclusions those facts cannot support.

SLS: propulsion for Artemis and deep space

NASA says SLS is its new deep-space exploration rocket. Its core stage will be powered on every mission by four RS-25 engines, formerly known as space shuttle main engines. A NASA test article says the core stage is more than 200 feet tall and 27.6 feet in diameter, and stores cryogenic liquid hydrogen.

The system also uses solid propulsion. NASA describes each SLS solid rocket booster as 17 stories tall, consuming about six tons of propellant every second, and as the largest and most powerful solid-propellant booster ever built for flight. Each produces more thrust than 14 four-engine aircraft. That is an illustrative comparison, not a total-launcher thrust figure.

After the initial ascent, the Interim Cryogenic Propulsion Stage (ICPS) uses one RL10 engine made by L3Harris. It burns liquid hydrogen and liquid oxygen and generates 24,750 pounds of thrust. NASA says RL10 provided the in-space propulsion that sent an uncrewed Orion spacecraft to the Moon on Artemis I, and is intended to reprise that role on the crewed Artemis II and III lunar missions. United Launch Alliance is contracted to produce stages for the first three Artemis missions.

New Glenn: published orbital capacity and seven BE-4s

NASA’s Launch Services Program rocket page states that New Glenn is powered by seven Blue Engine 4 (BE-4) engines. NASA lists a capacity of more than 13 metric tons to geostationary transfer orbit and 45 metric tons to low Earth orbit. Those destinations are not interchangeable: low Earth orbit is closer to Earth, while geostationary transfer orbit is a trajectory intended to approach the geostationary regime.

New Glenn is on NASA’s Launch Services II contract. This places it within the agency’s launch-services procurement framework, but the supplied material does not identify a specific assigned mission or establish an operational record.

Ariane 6 and the technical legacy of Ariane 5

ESA says Ariane 6’s core stage uses the liquid-fuelled Vulcain 2.1, an upgrade derived from Ariane 5’s Vulcain 2. P120C boosters add thrust at liftoff. The arrangement assigns complementary initial-ascent functions to the liquid core engine and boosters.

For historical context, a NASA Ariane 5 data sheet says it used 2.5 stages and four propulsion units. At liftoff, its two segmented solid motors each supplied more than 500 tonnes of thrust, augmenting a liquid-oxygen/liquid-hydrogen Vulcain core engine listed at 110 tonnes of thrust. The sheet also says Ariane 5 was upgraded to handle dual four-to-five-tonne payloads. These are Ariane 5 figures, not Ariane 6 specifications.

Reading specifications without forcing a ranking

The sources use different metrics: engine count, propellant type, thrust for one engine or booster, dimensions, and mass delivered to a particular orbit. Each measures a different part of a design. NASA notes that the Delta IV Medium-Plus RS-68 burned liquid hydrogen and liquid oxygen and produced 2,949 kilonewtons, or 663,000 pounds, of thrust. That helps identify a cryogenic-engine example, but is not directly comparable with another vehicle’s orbital capacity.

The available evidence therefore does not show which rocket is absolutely “better.” It supplies no comparable liftoff masses, complete mission profiles, costs, flight rate, reusability, reliability, launch dates or test outcomes. It does support three specific descriptions: SLS combines four RS-25s, large solid boosters and an RL10 stage for Artemis; NASA lists seven BE-4s and two orbital capacities for New Glenn; and Ariane 6 combines a liquid Vulcain 2.1 with P120C boosters.

An engineering landscape

These systems caution against reducing a rocket to its engine count. SLS organizes the described hardware around lunar and deep-space exploration; New Glenn is described through mass to two orbital destinations; and ESA highlights Vulcain continuity and P120C liftoff assistance for Ariane 6. Any superiority claim would require current, standardized information absent from the supplied sources.