The Space Launch System core stage, or simply core stage, is the main stage of the American Space Launch System (SLS) rocket, built by The Boeing Company in the NASA Michoud Assembly Facility. At 65 m (212 ft) tall and 8.4 m (27.6 ft) in diameter, the core stage contains approximately 987 t (2,177,000 lb) of its liquid hydrogen and liquid oxygen cryogenic propellants. Propelled by 4 RS-25 engines, the stage generates approximately 7.44 MN (1,670,000 lbf) of thrust, about 25% of the Space Launch System’s thrust at liftoff, for approximately 500 seconds, propelling the stage alone for the last 375 seconds of flight. The stage lifts the rocket to an altitude of approximately 162 km (531,380 ft) before separating, reentering the atmosphere over the Pacific Ocean.
The core stage originated in 2011, when the architecture of the Space Launch System as a whole was defined. In the aftermath of the end of the Space Shuttle program and the cancellation of its prospective replacement the Constellation program, the SLS emerged, a super-heavy lift launch vehicle intended for human spaceflight to the Moon. The core stage is the first newly-developed stage of the SLS; the ICPS (Interim Cryogenic Propulsion Stage) and five-segment boosters are adaptations of existing hardware, to be replaced by the Exploration Upper Stage and BOLE boosters respectively.
Production of core stages began by 2014, but was beset by numerous difficulties in production and testing which delayed the readiness of the first core stage by several years. The core stage first flew on November 16, 2022, on the Artemis 1 mission, in which it performed successfully. As of 2024, the second core stage is completed, with the third and fourth core stages in production and while work has begun for the fifth and sixth, their production pending the transfer of SLS operations to Deep Space Transport, the vehicle’s future operator.
Dream Chaser Tenacity (DC101) is the first Dream Chaser spacecraft expected to fly in space. Manufactured by the Sierra Nevada Corporation, it will first fly to the International Space Station as part of the SNC Demo-1 mission in 2025, under the CRS-2 contract.
The Sierra Nevada Corporation was awarded a CRS-2 contract for by NASA for six operational resupply spaceflights to the International Space Station. SNC Demo-1 is a demo flight that will precede the operational resupply flights if the mission is successful.
Tenacity and other Dream Chasers will be mated with a Shooting Star module, which will provide an additional 10,000 lb (4,500 kg) of payload capacity, in addition to the 2,000 lb (910 kg) carried by the space plane. The module will be separated from the Dream Chaser prior to reentry and burn up in the atmosphere, while the Dream Chaser vehicle will perform a runway landing to be reused.
Dream Chaser is an American reusable lifting-body space plane developed by Sierra Space. Originally intended as a crewed vehicle, the Dream Chaser Space System is set to be produced after the Dream Chaser Cargo System cargo variant is operational. The crewed variant is planned to carry up to seven people and cargo to and from low Earth orbit. Sierra plans to manufacture a fleet of the space plane.
The Dream Chaser was originally started in 2004 as a project of SpaceDev, a company that was later acquired by the Sierra Nevada Corporation (SNC) in 2008. In April 2021 the project was taken over by the Sierra Space Corporation (SSC), which at that time was spun off from the Sierra Nevada Corporation as its own fully independent company.
The cargo Dream Chaser is designed to resupply the International Space Station with both pressurized and unpressurized cargo. It is intended to be launched vertically on the Vulcan Centaur rocket and autonomously land horizontally on conventional runways. A proposed version to be operated by European Space Agency (ESA) would launch on an Arianespace vehicle.
The Dream Chaser space plane is designed to be launched on the top of a typical rocket and land like an airplane on a runway. The design has heritage going back decades. Currently, the Dream Chaser will resupply the ISS with cargo.
On-orbit propulsion of the Dream Chaser was originally proposed to be provided by twin hybrid rocket engines capable of repeated starts and throttling. At the time, the SSC’s predecessor, the SNC was also developing a similar hybrid rocket for Virgin Galactic’s SpaceShipTwo. In May 2014, SNC involvement in the SpaceShipTwo program ended.
After the acquisition of Orbitec LLC in July 2014, Sierra Nevada Corporation announced a major change to the propulsion system. The hybrid rocket engine design was dropped in favor of a cluster of Orbitec’s Vortex engines. The new unit would be a pressure-fed three-mode engine. At low- and mid-power regimes it uses monopropellant fuel – hydrogen peroxide – and in high-power demand, the engine adds injection of RP-1 fuel. This increased thrust will be useful to shorten the de-orbit burn duration of the Dream Chaser.
Its thermal protection system (TPS) is made up of silica-based tiles (for most of the belly and upper portion of the heat shield), and a new composite material called Toughened Unipiece Fibrous Reusable Oxidation Resistant Ceramic (TUFROC) to cover the nose and leading edges.
In 2019, it was announced that an expendable Shooting Star cargo module would be part of the Dream Chaser cargo system for CRS-2 flights. The module is a 15-foot-long (4.6 m) attachment to Dream Chaser that will allow the spacecraft to carry an additional 10,000 pounds (4,500 kg) of pressurized and unpressurized cargo to ISS. The module supports disposal of unwanted cargo by burning up upon re-entry.
In addition to carrying cargo, the Shooting Star module includes solar panels that supply up to 6 kW of electrical power. It also supplies active and passive thermal management; provides Dream Chaser translation and rotation capability via six mounted thrusters; and supports berthing or docking (in different configurations) to the ISS. Access from ISS to Dream Chaser will involve crew passing through Shooting Star (which supports a shirt-sleeve environment) and through a hatch that separates Shooting Star from Dream Chaser. Sierra Nevada says the module is capable of additional types of missions in LEO or to cis-lunar destinations; they have developed a free-flying variant with additional capabilities.
Solar sails (also known as lightsails, light sails, and photon sails) are a method of spacecraft propulsion using radiation pressure exerted by sunlight on large surfaces. A number of spaceflight missions to test solar propulsion and navigation have been proposed since the 1980s. The first spacecraft to make use of the technology was IKAROS, launched in 2010.
A useful analogy to solar sailing may be a sailing boat: the light exerting a force on the large surface is akin to a sail being blown by the wind. High-energy laser beams could be used as an alternative light source to exert much greater force than would be possible using sunlight, a concept known as beam sailing. Solar sail craft offer the possibility of low-cost operations combined with high speeds (relative to chemical rockets) and long operating lifetimes. Since they have few moving parts and use no propellant, they can potentially be used numerous times for the delivery of payloads.
Solar sails use a phenomenon that has a proven, measured effect on astrodynamics. Solar pressure affects all spacecraft, whether in interplanetary space or in orbit around a planet or small body. A typical spacecraft going to Mars, for example, will be displaced thousands of kilometers by solar pressure, so the effects must be accounted for in trajectory planning, which has been done since the time of the earliest interplanetary spacecraft of the 1960s. Solar pressure also affects the orientation of a spacecraft, a factor that must be included in spacecraft design.
Europa Clipper (previously known as Europa Multiple Flyby Mission) is a space probe in development by NASA. Planned for launch in October 2024, the spacecraft is being developed to study the Galilean moon Europa through a series of flybys while in orbit around Jupiter.
This mission is a scheduled flight of the Planetary Science Division, designated a Large Strategic Science Mission, and funded under the Planetary Missions Program Office’s Solar System Exploration program as its second flight. It is also supported by the new Ocean Worlds Exploration Program. Europa Clipper will perform follow-up studies to those made by the Galileo spacecraft during its eight years (1995 – 2003) in Jupiter orbit, which indicated the existence of a subsurface ocean underneath Europa’s ice crust. Plans to send a spacecraft to Europa were initially conceived with projects such as Europa Orbiter and Jupiter Icy Moons Orbiter, in which a spacecraft would be injected into orbit around Europa. However, due to the adverse effects of radiation from Jupiter’s magnetosphere in Europa orbit, it was decided that it would be safer to inject a spacecraft into an elliptical orbit around Jupiter and make 44 close flybys of the moon instead. The mission began as a joint investigation between the Jet Propulsion Laboratory (JPL) and the Applied Physics Laboratory (APL), and will be built with a scientific payload of nine instruments contributed by JPL, APL, Southwest Research Institute, University of Texas at Austin, Arizona State University and University of Colorado Boulder. The upcoming mission complements ESA’s Jupiter Icy Moons Explorer launch in 2023, which will fly-by Europa twice and Callisto multiple times before moving into orbit around Ganymede.
The mission is scheduled to launch in October 2024 aboard a Falcon Heavy, during a 21-day launch window. The spacecraft will use gravity assists from Mars in February 2025 and Earth in December 2026, before arriving at Europa in April 2030.
Dream Chaser is an American reusable lifting-body spaceplane being developed by Sierra Space. Originally intended as a crewed vehicle, the Dream Chaser Space System is set to be produced after the Dream Chaser Cargo System cargo variant is operational. The crewed variant is planned to carry up to seven people and cargo to and from low Earth orbit.
The cargo Dream Chaser is designed to resupply the International Space Station with both pressurized and unpressurized cargo. It is intended to launch vertically on the Vulcan Centaur rocket and autonomously land horizontally on conventional runways. A proposed version to be operated by ESA would launch on an Arianespace vehicle.
Starship is an American two-stage super heavy lift launch vehicle under development by the aerospace company SpaceX. It is currently the largest and most powerful rocket ever flown. Starship is intended to be fully reusable, which means both stages will be recovered after a mission and reused.
The Starship launch vehicle is designed to supplant SpaceX’s Falcon 9 and Falcon Heavy rockets, expand SpaceX’s Starlink satellite constellation, and launch crews to both low Earth orbit and Mars. The vehicle is fundamental to SpaceX’s ambition of colonizing Mars. SpaceX plans to use Starship vehicles as tankers, refueling other Starships to allow missions to geosynchronous orbit, the Moon, and Mars. A planned lunar lander variant of Starship was contracted by NASA to land astronauts on the Moon as part of the Artemis program by 2025, later delayed to September 2026.
Starship consists of the Super Heavy booster and the Starship spacecraft, which are both powered by Raptor engines, which burn liquid methane and liquid oxygen. Both stages are constructed primarily of stainless steel, instead of the carbon composite used in a series of prior designs. The booster is designed to use its engines to slow itself down, before being caught by a pair of mechanical arms attached to the launch tower. The Starship spacecraft is designed to be protected during atmospheric reentry by its thermal protection system, using a ‘belly flop’ maneuver where the spacecraft turns from a horizontal to a vertical position from which it lands using its engines.
SpaceX has stated that a long-term goal for the Starship system is to achieve frequent space launches at low cost. Development follows an iterative and incremental approach involving test flights of prototype vehicles which are often destructive. The first flight test of the full Starship system took place on 20 April 2023, lifting-off with three engines out and ending four minutes after launch due to a loss of control, resulting in the destruction of the launch vehicle. The second flight test of the vehicle took place on 18 November 2023, achieving stage separation with the Super Heavy booster exploding roughly 30 seconds later following multiple engine failures during its boostback burn. The upper stage was lost nearly eight minutes after launch prior to reaching orbit.