|
AQT-D
AQT-D (Aqua Thruster-Demonstrator) was a nanosatellite project of the University of Tokyo (UT) Space Propulsion Laboratory with the purpose of testing water-fueled propulsion. The satellite was a CubeSat of 3U size; 1U was occupied by the propulsion system, while the remaining 2U was for the spacecraft bus. AQT-D was carried to space inside the pressurized section of Kounotori 8, a Japanese resupply vehicle for the International Space Station (ISS). Kounotori 8 was launched on 24 September 2019. After arriving at the ISS, AQT-D was deployed to space on 20 November 2019 using the JEMRMS robotic arm at the space station's Kibō laboratory module. The AQT-D project was led by Jun Asakawa of the University of Tokyo. AQT-D reentered the atmosphere on 20 April 2022. Spacecraft AQT-D's spacecraft bus was based on Tasuki (TRICOM-1R), a previous satellite developed by the University of Tokyo and launched in 2017. The satellite was equipped with antennas for store and forward co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kounotori 8
, also known as HTV-8 was the 8th flight of the H-II Transfer Vehicle, a robotic cargo spacecraft to resupply the International Space Station. It was launched on 24 September 2019, 16:05:05 UTC. Spacecraft Major changes from previous Kounotori are: * Replacement of Earth sensor with star tracker for spacecraft attitude control * New cargo racks developed for HTV-X which allows 30% more Cargo Transfer Bags (CTB) to be carried in the Pressurized Logistics Carrier (PLC). (316 CTBs for Kounotori 8, compared to 248 CTBs of Kounotori 6) Cargo Kounotori 8 carries about 5300 kg of cargo, consisting of 3400 kg in the pressurized compartment and 1900 kg in the unpressurized compartment. Cargo in the Pressurized Logistics Carrier (PLC) include: * JAXA experiment Cell Biology Experiment Facility-Left (CBEF-L) * JAXA experiment Sony Optical Link for ISS (SOLISS), a satellite optical communication demonstration co-developed with * JAXA experiment Hourglass, which will ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanosatellite
A small satellite, miniaturized satellite, or smallsat is a satellite of low mass and size, usually under . While all such satellites can be referred to as "small", different classifications are used to categorize them based on mass. Satellites can be built small to reduce the large economic cost of launch vehicles and the costs associated with construction. Miniature satellites, especially in large numbers, may be more useful than fewer, larger ones for some purposes – for example, gathering of scientific data and radio relay. Technical challenges in the construction of small satellites may include the lack of sufficient power storage or of room for a propulsion system. Rationales One rationale for miniaturizing satellites is to reduce the cost; heavier satellites require larger rockets with greater thrust that also have greater cost to finance. In contrast, smaller and lighter satellites require smaller and cheaper launch vehicles and can sometimes be launched in multipl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newton (unit)
The newton (symbol: N) is the unit of force in the International System of Units (SI). It is defined as 1 kg⋅m/s, the force which gives a mass of 1 kilogram an acceleration of 1 metre per second per second. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion. Definition A newton is defined as 1 kg⋅m/s (it is a derived unit which is defined in terms of the SI base units). One newton is therefore the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in the direction of the applied force. The units "metre per second squared" can be understood as measuring a rate of change in velocity per unit of time, i.e. an increase in velocity by 1 metre per second every second. In 1946, Conférence Générale des Poids et Mesures (CGPM) Resolution 2 standardized the unit of force in the MKS system of units to be the amount needed to accelerate 1 kilogram of mass at the rate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Launched In 2019
A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, and transportation of humans and cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket). On a sub-orbital spaceflight, a space vehicle enters space and then returns to the surface without having gained sufficient energy or velocity to make a full Earth orbit. For orbital spaceflights, spacecraft enter closed orbits around the Earth or around other celestial bodies. Spacecraft used for human spaceflight carry people on board as crew or passengers from start or on orbit (space stations) only, whereas those used for robotic space missions operate either autonomously or telerobotically. Robotic spacecraft used to support scientific res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2019 In Japan
Events in the year 2019 in Japan. Incumbents *Emperor: Akihito (until 30 April), Naruhito (since 1 May) *Prime Minister: Shinzō Abe Governors * Aichi Prefecture: Hideaki Omura *Akita Prefecture: Norihisa Satake *Aomori Prefecture: Shingo Mimura *Chiba Prefecture: Kensaku Morita *Ehime Prefecture: Tokihiro Nakamura *Fukui Prefecture: Issei Nishikawa (until 23 April); Tatsuji Sugimoto (starting 23 April) *Fukuoka Prefecture: Hiroshi Ogawa *Fukushima Prefecture: Masao Uchibori *Gifu Prefecture: Hajime Furuta *Gunma Prefecture: Masaaki Osawa (until 28 July); Ichita Yamamoto (starting 28 July) * Hiroshima Prefecture: Hidehiko Yuzaki *Hokkaido: Harumi Takahashi (until 23 April); Naomichi Suzuki (starting 23 April) *Hyogo Prefecture: Toshizō Ido *Ibaraki Prefecture: Kazuhiko Ōigawa * Ishikawa Prefecture: Masanori Tanimoto *Iwate Prefecture: Takuya Tasso *Kagawa Prefecture: Keizō Hamada *Kagoshima Prefecture: Satoshi Mitazono *Kanagawa Prefecture: Yuji Kuroiwa *Kochi Prefecture: M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CubeSats
A CubeSat is a class of miniaturized satellite based around a form factor consisting of cubes. CubeSats have a mass of no more than per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSats are put into orbit by deployers on the International Space Station, or launched as secondary payloads on a launch vehicle. , more than 1,600 CubeSats have been launched. In 1999, California Polytechnic State University (Cal Poly) professor Jordi Puig-Suari and Bob Twiggs, a professor at Stanford University Space Systems Development Laboratory, developed the CubeSat specifications to promote and develop the skills necessary for the design, manufacture, and testing of small satellites intended for low Earth orbit (LEO) that perform a number of scientific research functions and explore new space technologies. Academia accounted for the majority of CubeSat launches until 2013, when more than half of launches were for non-academic purposes, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellites Of Japan
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have a method of communication to ground stations, called transponders. Many satellites use a standardized bus to save cost and work, the most popular of which is small CubeSats. Similar satellites can work together as a group, forming constellations. Because of the high launch cost to space, satellites are designed to be as lightweight and robust as possible. Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz. Satellites are placed from the surface to orbit by launch vehicles, high enough to avoid orbital decay by the atmosphere. Satellites can then change or maintain the orbit by propulsion, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EQUULEUS
Equuleus ( ) is a constellation of stars that are visible in the night sky. Its name is Latin for "little horse", a foal. Located just north of the celestial equator, it was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations. It is the second smallest of the modern constellations (after Crux), spanning only 72 square degrees. It is also very faint, having no stars brighter than the fourth magnitude. Notable features Stars The brightest star in Equuleus is Alpha Equulei, traditionally called Kitalpha, a yellow star magnitude 3.9, 186 light-years from Earth. Its traditional name means "the section of the horse". There are few variable stars in Equuleus. Only around 25 are known, most of which are faint. Gamma Equulei is an alpha CVn star, ranging between magnitudes 4.58 and 4.77 over a period of around 12½ minutes. It is a white star 115 light-years from Earth, and has an optical companion of magnitude ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Impulse
Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine (a rocket using propellant or a jet engine using fuel) creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse is exactly proportional to the effective exhaust gas velocity. A propulsion system with a higher specific impulse uses the mass of the propellant more efficiently. In the case of a rocket, this means less propellant needed for a given delta-v, so that the vehicle attached to the engine can more efficiently gain altitude and velocity. In an atmospheric context, specific impulse can include the contribution to impulse provided by the mass of external air that is accelerated by the engine in some way, such as by an internal turbofan or heating by fuel combustion participation then thrust expansion or by external propeller. Jet engines breathe external air for both combustion and by-pass, and therefore have a much higher specific impulse than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Attitude Control
Spacecraft attitude control is the process of controlling the orientation of a spacecraft (vehicle/satellite) with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle attitude requires sensors to measure vehicle orientation, actuators to apply the torques needed to orient the vehicle to a desired attitude, and algorithms to command the actuators based on (1) sensor measurements of the current attitude and (2) specification of a desired attitude. The integrated field that studies the combination of sensors, actuators and algorithms is called guidance, navigation and control (GNC). Overview A spacecraft's attitude must typically be stabilized and controlled for a variety of reasons. It is often needed so that the spacecraft high-gain antenna may be accurately pointed to Earth for communications, so that onboard experiments may accomplish precise pointing for accurate collectio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reaction Control System
A reaction control system (RCS) is a spacecraft system that uses thrusters to provide attitude control and translation. Alternatively, reaction wheels are used for attitude control. Use of diverted engine thrust to provide stable attitude control of a short-or-vertical takeoff and landing aircraft below conventional winged flight speeds, such as with the Harrier "jump jet", may also be referred to as a reaction control system. Reaction control systems are capable of providing small amounts of thrust in any desired direction or combination of directions. An RCS is also capable of providing torque to allow control of rotation (roll, pitch, and yaw). Reaction control systems often use combinations of large and small ( vernier) thrusters, to allow different levels of response. Uses Spacecraft reaction control systems are used for: * attitude control during different stages of a mission; * station keeping in orbit; * close maneuvering during docking procedures; * control o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Impulse
Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine (a rocket using propellant or a jet engine using fuel) creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse is exactly proportional to the effective exhaust gas velocity. A propulsion system with a higher specific impulse uses the mass of the propellant more efficiently. In the case of a rocket, this means less propellant needed for a given delta-v, so that the vehicle attached to the engine can more efficiently gain altitude and velocity. In an atmospheric context, specific impulse can include the contribution to impulse provided by the mass of external air that is accelerated by the engine in some way, such as by an internal turbofan or heating by fuel combustion participation then thrust expansion or by external propeller. Jet engines breathe external air for both combustion and by-pass, and therefore have a much higher specific impulse than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> EQUULEUS")
