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Delta IV Rocket
Delta IV was a group of five expendable launch systems in the Delta rocket family. It flew 45 missions from 2002 to 2024. Originally designed by Boeing's Defense, Space and Security division for the Evolved Expendable Launch Vehicle (EELV) program, the Delta IV became a United Launch Alliance (ULA) product in 2006. The Delta IV was primarily a launch vehicle for United States Air Force (USAF) military payloads, but was also used to launch a number of United States government non-military payloads and a single commercial satellite. The Delta IV had two main versions which allowed the family to cover a range of payload sizes and masses: the Medium (which had four configurations) and Heavy. The final flight of Medium occurred in 2019. The final flight of Heavy was in April 2024. Delta IV vehicles were built in the ULA facility in Decatur, Alabama. Final assembly was completed at the launch site by ULA: at the horizontal integration facility for launches from SLC-37B pad at Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DSCS
The Defense Satellite Communications System (DSCS) is a United States Space Force satellite constellation that provides the United States with military communications to support globally distributed military users. Beginning in 2007, DSCS began being replaced by the Wideband Global SATCOM system. A total of 14 DSCS-III satellites were launched between the early 1980s and 2003. Two satellites were launched aboard the Space Shuttle ''Atlantis'' in 1985 during the STS-51-J flight. As of 14 September 2021, six DSCS-III satellites were still operational. DSCS operations are currently run by the 4th Space Operations Squadron out of Schriever Space Force Base. Background DSCS went through three major phases — IDCSP (Interim Defense Communication Satellite Program), DSCS-II, and DSCS-III. Since the first launch, DSCS has been the "workhorse" of military satellite communications. All DSCS III satellites have exceeded their 10-year design life. The National Science Foundation use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium
Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has a great affinity towards oxygen, passivation (chemistry), forming a protective layer of aluminium oxide, oxide on the surface when exposed to air. It visually resembles silver, both in its color and in its great ability to reflect light. It is soft, magnetism, nonmagnetic, and ductility, ductile. It has one stable isotope, 27Al, which is highly abundant, making aluminium the abundance of the chemical elements, 12th-most abundant element in the universe. The radioactive decay, radioactivity of aluminium-26, 26Al leads to it being used in radiometric dating. Chemically, aluminium is a post-transition metal in the boron group; as is common for the group, aluminium forms compounds primarily in the +3 oxidation state. The aluminium cation Al3+ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxyl-terminated Polybutadiene
Hydroxyl-terminated polybutadiene (HTPB) is an oligomer of butadiene terminated at each end with a hydroxyl functional group. It reacts with isocyanates to form polyurethane polymers. HTPB is a translucent liquid with a color similar to wax paper and a viscosity similar to corn syrup. The properties vary because HTPB is a mixture rather than a pure compound, and it is manufactured to meet customers' specific requirements. A typical HTPB is R-45HTLO. This product consists of oligomeric units typically containing 40–50 butadiene molecules bonded together, with each end of the chain terminated with a hydroxyl Hgroup: R-45HTLO has a functionality of 2.4-2.6, which means that there is (approximately) one additional hydroxyl group located along the chain for every two oligomeric units. This provides side-to-side linkage for a stronger cured product. HTPB is usually cured by an addition reaction with di- or poly-isocyanate compounds. Uses Materials production Polyurethanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Perchlorate Composite Propellant
Ammonium perchlorate composite propellant (APCP) is a solid rocket propellant. It differs from many traditional solid rocket propellants such as black powder or zinc-sulfur, not only in chemical composition and overall performance but also by being cast into shape, as opposed to powder pressing as with black powder. This provides manufacturing regularity and repeatability, which are necessary requirements for use in the aerospace industry. Uses Ammonium perchlorate composite propellant is typically for aerospace rocket propulsion where simplicity and reliability are desired and specific impulses (depending on the composition and operating pressure) of are adequate. Because of these performance attributes, APCP has been used in the Space Shuttle Solid Rocket Boosters, aircraft ejection seats, and specialty space exploration applications such as NASA's Mars Exploration Rover descent stage retrorockets. In addition, the high-power rocketry community regularly uses APCP i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphite-Epoxy Motor
The Graphite-Epoxy Motor (GEM) is a family of solid rocket boosters developed in the late 1980s and used since 1990. GEM motors are manufactured with carbon-fibre-reinforced polymer casings and a fuel consisting of HTPB-bound ammonium perchlorate composite propellant. GEM is produced by Northrop Grumman Space Systems. GEM boosters are used on the Atlas V and were previously used on the Delta II, Delta III, and Delta IV launch vehicles. A new variant, the GEM 63XL, flew as part of the Vulcan Centaur launch vehicle on 8 January 2024. Variants Active GEM 63 The GEM 63 was developed by Orbital ATK as a low-cost drop-in replacement for the Aerojet Rocketdyne AJ-60A solid rocket booster used on the Atlas V. Its overall dimensions are very similar to that of the motor it replaces. The Atlas V first flew with the GEM 63 in 2020 on the NROL-101 launch. The booster offers higher performance at about half the cost of the AJ-60A boosters formerly used on the Atlas V. GEM 63XL T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parker Solar Probe
The Parker Solar Probe (PSP; previously Solar Probe, Solar Probe Plus or Solar Probe+) is a NASA space probe launched in 2018 to make observations of the Stellar corona, Sun's outer corona. It used repeated Gravity assist, gravity assists from Venus to develop an eccentric orbit, approaching within 9.86 solar radius, solar radii (6.9 million km or 4.3 million miles) from the center of the Sun. At its closest approach in 2024, its speed relative to the Sun was or 191 km/s (118.7 mi/s), which is 0.064% the speed of light. It is the fastest object ever built on Earth. The project was announced in the fiscal 2009 budget year. Johns Hopkins University Applied Physics Laboratory designed and built the spacecraft, which was launched on 12 August 2018. It became the first NASA spacecraft named after a living person, honoring physicist Eugene Parker, Eugene Newman Parker, professor emeritus at the University of Chicago. On 29 October 2018, at about 18:04 UTC, the spacecraft became t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exploration Flight Test 1
Exploration Flight Test-1 or EFT-1 (previously known as Orion Flight Test 1 or OFT-1) was a technology demonstration mission and the first flight test of the crew module portion of the Orion spacecraft. Without a crew, it was launched on 5 December 2014 at 12:05 UTC (7:05 am EST, local time at the launch site) by a Delta IV Heavy rocket from Space Launch Complex 37B at the Cape Canaveral Air Force Station. The mission was a four-hour, two-orbit test of the Orion crew module featuring a high apogee on the second orbit and concluding with a high-energy reentry at around . This mission design corresponds to the Apollo 2/3 missions of 1966, which validated the Apollo flight control system and heat shield at re-entry conditions planned for the return from lunar missions. Objectives EFT-1 tested various systems of the crew module portion of the Orion spacecraft, including separation events, avionics, heat shielding, parachutes, and recovery operat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wideband Global SATCOM
The Wideband Global SATCOM system (WGS) is a high capacity United States Space Force satellite communications system planned for use in partnership by the United States Department of Defense (DoD), Canadian Department of National Defence (DND) and the Australian Department of Defence. The system is composed of the ''Space Segment'' satellites, the ''Terminal Segment'' users and the ''Control Segment'' operators. DoD wideband satellite communication services are currently provided by a combination of the existing Defense Satellite Communications System (DSCS) and Global Broadcast Service (GBS) satellites. According to United Launch Alliance, quoted on ''Spaceflight Now'', "A single WGS spacecraft has as much bandwidth as the entire existing DSCS constellation." WGS operations are currently run by the 4th Space Operations Squadron, out of Schriever Space Force Base, as well as the 53rd Space Operations Squadron. Mission The constellation of WGS satellites increases the commun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GPS Block IIF
GPS Block IIF, or GPS IIF is an interim class of GPS (satellite) which were used to bridge the gap between previous Navstar Global Positioning System generations until the GPS Block III satellites became operational. They were built by Boeing, operated by the United States Air Force, and launched by the United Launch Alliance (ULA) using Evolved Expendable Launch Vehicles (EELV). They are the final component of the Block II GPS constellation to be launched. On 5 February 2016, the final Block IIF satellite was successfully launched, completing the series. The spacecraft have a mass of and a design life of 12 years. Like earlier GPS satellites, Block IIF spacecraft operate in semi-synchronous medium Earth orbits, with an altitude of approximately , and an orbital period of twelve hours. The satellites supplement and partially replace the GPS Block IIA satellites that were launched between 1990 and 1997 with a design life of 7.5 years. The final satellite of the Block IIA ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geostationary Operational Environmental Satellite
The Geostationary Operational Environmental Satellite (GOES), operated by the United States' National Oceanic and Atmospheric Administration (NOAA)'s National Environmental Satellite, Data, and Information Service division, supports weather forecasting, severe storm tracking, and meteorology research. Spacecraft and ground-based elements of the system work together to provide a continuous stream of environmental data. The National Weather Service (NWS) and the Meteorological Service of Canada use the GOES system for their North American weather monitoring and forecasting operations, and scientific researchers use the data to better understand land, atmosphere, ocean, and climate dynamics. The GOES system uses geosynchronous equatorial satellites that, since the launch of SMS-1 in 1974, have been a basic element of U.S. weather monitoring and forecasting. The procurement, design, and manufacture of GOES satellites is overseen by NASA. NOAA is the official provider of both G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
