Space tug
A space tug (English: space tug ) is a spacecraft , with the cargo in space from one orbit is transported into another orbit of different energy characteristics. An example would be moving a spacecraft from near-earth orbit (LEO) to a higher energy orbit such as geostationary orbit, lunar orbit, or an escape orbit.
The term is often used for reusable space-based vehicles. Some previously proposed or built space tugs include the 1970s NASA STS proposal or the proposed Russian Parom, and have sometimes been used to refer to one-way upper stages like the Russian Fregat .
background
The space tug was first considered in the post-war period as a carrier for a permanent, earth-orbiting space station. It was used by science fiction writer Murray Leinster as the title of a novel published in 1953 as a sequel to Space Platform, a novel about one such space station.
Unrealized projects
NASA Space Transportation System
A reusable space tug was studied by NASA as part of a reusable space transportation system (STS) in the late 1960s and early 1970s. This consisted of a basic drive module to which a crew module or other payload could be connected. Optional landing legs could be added to allow payloads to land on the moon's surface. This, along with all of the other elements of STS with the exception of the space shuttle, was never funded after the NASA budget cut in the 1970s as a result of the Apollo program.
In 1994 the term space tug appeared as an alternative designation for an "FGB energy block spacecraft", later known as the Sarja module, for the expansion of the Alpha space station, which is currently being planned, to become the International Space Station (then still International Space Station Alpha ) .
Space shuttle time
Single-use upper grades
The space shuttle program took on the role of high energy orbital transfer by developing a single-stage solid fuel payload support module and a two-stage inertial upper stage.
A more powerful Centaur-G stage with liquid hydrogen was developed for use in the space shuttle, but was canceled as too dangerous after the Challenger disaster .
Orbital Maneuvering Vehicle
NASA, along with their plans for the ISS space station, developed another space tug design called the Orbital Maneuvering Vehicle (OMV). The OMV would have been a reusable spacecraft that could have changed the orbit of satellites like the Hubble Space Telescope . In 1984, the preliminary design studies for orbital maneuvering vehicles (OMV) were initiated by a competitive tendering process with system studies carried out by TRW , Martin Marietta and LTV Corporation .
Parom
The Russian company RKK Energia proposed a space tug called Parom in 2005 . This would allow the proposed manned Kliper spaceship as well as cargo and fuel supply modules to be transported to the ISS. Maintaining the tug in space would have allowed a less massive Kliper and launched with a smaller booster than the original Kliper design.
SHERPA
Spaceflight Inc. planned to develop the SHERPA system, which would build on the capabilities of the Spaceflight Secondary Payload System (SSPS) and integrate propulsion and power generation subsystems that would create a propelling tug for maneuvering to an optimal orbit for placing secondary payloads. The concept was abandoned in favor of a non-powered transport bracket , which was used in duplicate on the Rideshare flight SSO-A in December 2018.
Jupiter
Lockheed Martin submitted a conceptual proposal to NASA in 2015 for a design called the Jupiter Space Tug, based on the designs of two previous Lockheed Martin spaceships - Mars Atmosphere and Volatile Evolution Mission and Juno - and a robotic arm from MDA derived from the technology used in Canadarm , the robotic arm technology previously used in the space shuttle. In addition to the Jupiter spacecraft itself, the Lockheed concept included the use of a new cargo transport module called the Exoliner with a diameter of 4.4 m to transport cargo to the ISS. Exoliner is based on the Automated Transfer Vehicle developed by ESA in the 2000s and was to be developed together with Thales Alenia Space . However, NASA did not want to pay for the project, which is why it was discarded.
Used space tugs
TKS and Progress as space tugs
In 1987 the propulsion and navigation unit of the Soviet transport spacecraft TKS-5 was used to maneuver the Kwant module out of its orbit after take-off to the Mir space station and to dock there. TKS-5 was then disconnected to burn up in the atmosphere. The same procedure was used to bring the Pirs (2001) and Poisk (2009) modules to the International Space Station . There, however, the drive part of Progress space freighters was used as a tug. A Progress transporter with its drive unit should also take over the maneuvering when uncoupling and disposing of the Pirs module in order to free up the docking connector for the planned Nauka module.
Missile upper stages
Optional additional stages ( kick stages ) are available for various launchers , which are transported inside the payload fairing during take-off and transport the payload to a higher orbit after the lower rocket stages have burned out. Examples are the Russian Fregat and Blok-D , the American Star 48 and the Curie upper stage of the small rocket Electron developed in New Zealand .
Example: ISRO PAM-G
The Indian space research organization has built an upper tier called PAM-G (Payload Assist Module for GSLV ) which can be used to move payloads directly from low-earth orbits to MEO or GEO orbits. PAM-G is powered by a hypergolic fluid motor with restart function, which comes from the fourth stage of PSLV. Since 2013, ISRO has implemented the structure, control systems and motors of PAM-G and carried out hot tests. PAM-G forms the fourth stage of the GSLV Mk2C launcher, which sits on top of the cryogenic third stage of the GSLV.
Current projects
Momentus Vigoride
Artemis Transfer Stages
The Artemis program NASA plans to use partially reusable three-stage moon countries. One of the main elements is the transfer stage that would take the lander from orbit the Lunar Orbital Platform gateway to low orbit. Future releases may return to the Lunar Orbital Platform gateway for refueling and reuse with another lander. Northrop Grumman has proposed building a transfer stage based on his Cygnus spaceship .
Similar systems
Mission Extension Vehicle
The Mission Extension Vehicle (MEV) from Northrop Grumman Space Systems docks like a spacecraft to a satellite and takes over its propulsion. The main purpose of the MEV is not to move the payload into a new orbit, but to stabilize an existing orbit. It also remains permanently connected to the satellite.
Individual evidence
- ^ Space Tug . In: Astronautix . Retrieved July 25, 2014.
- ^ The Space Shuttle Decision: NASA's Search for a Reusable Space Vehicle . In: nasa.gov . Retrieved July 25, 2014: “Because a rising tide lifts all boats, NASA's flight rates during the 1960s had been buoyed powerfully by the agency's generous budgets. The OMB had no intention of granting such largesse during the 1970s. "
- ↑ United States General Accounting Office (Ed.): SPACE STATION, Impact of the Expanded Russian Role on Funding and Research . June 21, 1994, p. 1 and 3 (English, gao.gov [PDF; accessed January 30, 2020]).
- ^ Long-forgotten Shuttle / Centaur boosted Cleveland's NASA center into manned space program and controversy . In: Cleveland.com . Retrieved July 25, 2014.
- ^ NASA's New Launch Systems May Include the Return of the Space Tug . In: SpaceRef . August 7, 2005. Retrieved July 25, 2014.
- ↑ Linking Space Station & Mars . In: Wired . December 2013. Retrieved July 25, 2014.
- ↑ Parom orbital tug . In: RussianSpaceWeb . February 9, 2010. Retrieved July 26, 2014.
- ↑ Lighter Kliper could make towed trip to ISS . In: Flight Global . November 2005. Retrieved July 26, 2014.
- ↑ 'Jupiter' Space Tug Could Deliver Cargo To The Moon . March 12, 2015. Accessed March 17, 2015.
- ↑ Jeff Foust: Lockheed Martin Pitches Reusable Tug for Space Station Resupply , Space News. March 13, 2015.
- ^ Greg Avery: Lockheed Martin proposes building ISS cargo ship for NASA . In: Denver Business Journal , March 12, 2015. Retrieved March 13, 2015.
- ^ S Somanath: ISRO's Current Launch Capabilities & Commercial Opportunities . Archived from the original on September 3, 2013. Retrieved July 8, 2014.
- ^ N. Gopal Raj: Upgrading Indian rockets for future Mars missions . Thehindu.com. October 1, 2014. Retrieved March 17, 2015.
- ↑ Annual Report . Archived from the original on February 25, 2014. Retrieved July 8, 2014.
- ↑ Outcome Budget 2010–2011 . Archived from the original on October 13, 2011. Retrieved July 8, 2014.
- ↑ Outcome Budget of the Department of Space Government of India 2009-2010 . Archived from the original on November 23, 2010. Retrieved July 8, 2014.
- ↑ GSLV . Space.skyrocket.de. Retrieved March 17, 2015.