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Spacecraft propulsion is any method used to accelerate spacecraft and artificial satellites. There are many different methods. Each method has drawbacks and advantages, and spacecraft propulsion is an active area of research. However, most spacecraft today are propelled by forcing a gas from the back/rear of the vehicle at very high speed through a supersonic de Laval nozzle. This sort of engine is called a rocket engine. All current spacecraft use chemical rockets (bipropellant or solid-fuel) for launch, though some (such as the Pegasus rocket and SpaceShipOne) have used air-breathing engines on their first stage. Most satellites have simple reliable chemical thrusters (often monopropellant rockets) or resistojet rockets for orbital station-keeping and some use momentum wheels for attitude control. Soviet bloc satellites have used electric propulsion for decades, and newer Western geo-orbiting spacecraft are starting to use them for north-south stationkeeping. Interplanetary vehicles mostly use chemical rockets as well, although a few have experimentally used ion thrusters (a form of electric propulsion) to great success. From Wikipedia under the
GNU Free Documentation License  skycontrol.net 934px x 625px | 333.60kB [source page] the moon s orbit During the next 80 days spacecraft controllers will test and calibrate the myriad of spacecraft systems and subsystems ensuring Dawn is ready for the long journey ahead Rising above a cloud filled horizon the Delta II rocket carrying the Dawn spacecraft roared into the sky Image credit NASA Dawn will travel back in time by probing deep into the From Yahoo Image Search: "spacecraft propulsion"  themefortheday.blogspot.com Christopher ue, 09 Mar 2010 09:38:00 GM This book is recommended as an important and worthwhile contribution to the literature on electric propulsion and its use for . spacecraft propulsion. and flight control. Description on Rail Gun propulsion: An inductor energy storage bank ...  themoneytimes.com Ishita Sood Wed, 17 Mar 2010 09:33:50 GM Discovered in 1610, Jupiter has been explored by Pioneer and Voyager, and recently, the new Horizons . spacecraft. in February 2007. The image above was captured by Voyager 1 in 1979. NASA's latest discovery gives the first detailed image of Jupiter's Great Red Spot. The space agency says it is a ... This is our first detailed look inside the biggest storm of the solar system, said Glenn Orton, a senior research scientist at NASA's Jet . Propulsion. Laboratory in California. ...  dailygalaxy.com Casey Kazan Daily Galaxy Editorial Staff Sun, 07 Mar 2010 12:54:17 GM Unless disabled by fierce sandstorms, our rovers are in constant realtime communication with their masters at the Jet . Propulsion. Laboratory, as will the New Horizons . spacecraft. now heading for Pluto with human monitors watching over it. ... From Google Blog Search: "spacecraft propulsion"  news.google.com Tehran Times It shows they really do have confidence that the spacecraft is healthy and able to do good science. The Chandra X-ray Observatory was initially built for ... and more » news.google.com Aviation Week One approach to the problem is the Space Tracking and Surveillance System satellite, which uses infrared sensors on two spacecraft to track missiles. ... and more » news.google.com Cryptome.org Advanced autonomous satellites systems, may include the following subsystems: laser communications systems, high-powered electronic propulsion systems, ... From Google News Search: "spacecraft propulsion" MagBeam propulsion for interstellar probes, do you think this technology has potential for future spacecraft? Q. here are a couple links. Asked by Hellbent 2.0 system reboot - Mon Jan 14 06:26:16 2008 - - 1 Answers - 0 Comments A. From the links you have given me to look at i think that this might just be one of those new technologies that most people don't show any interest in but end up becoming the back bone of space flight in the future, the idea of using a magnetic sail pushed by charged particles has kind of a science fiction feel to it but from what i have read from your links it is very real, maybe in 10 or 20 years from now everyone will be using them. Answered by Funny Shy Guy :) - Mon Jan 14 06:46:17 2008 Are there materials in space to power a nuclear powered spacecraft? Q. so that as the space craft travels in continuously scoops up and harvests these materials and converts them to propulsion to keep the craft going for greatly increasing speeds? How would that work? and what speeds could be reached by such a craft being perpetually thrusted forward for say 6 months? Asked by jesswzmn - Sat May 31 20:32:06 2008 - - 2 Answers - 0 Comments A. The materials are there, but they're not just floating around all over space. Let's say you were going to power it by uranium (only formed by supernova explosions), you would have to pick it up either from planets or fly through recently exploded supernovae. You couldn't reach any of those in 6 months. Answered by Bryan A JPA - Sat May 31 20:38:17 2008 Please help, I am totally stuck?
Q. The spacecraft is designed to leave the surface of Mars with the first stage of its propulsion system and be put into Martian orbit. Then, the second stage is used to boost the spacecraft from Martian orbit into an interplanetary trajectory and return to Earth. If the spacecraft is in Martian orbit at an altitude of 378 km, what is the velocity (in km/s) required to escape the gravitational attraction of Mars. Note that the velocity direction and magnitude required to actually return to Earth may be different. Asked by pleasehelp - Sat Mar 29 02:04:44 2008 - - 2 Answers - 0 Comments A. Escape velocity v^2 = (2Gm)/r. First, however, I have to assume the space ship is already in orbit. Orbital velocity v^2 = (Gm/r). Escape velocity therefore is just orbital velocity times the square root of two. BTW G (gravitational constant) = 6.67428 * 10^-11 m^3 kg^-1 s^-2. The radius of mars according to Wiki is 3,396.2 km equatorially. Add 378 km and the radius of the ship from Mars is 3,774,200 meters. 6.67428*10^-11(G) * 6.4185*10^23(mass of Mars) / 3,774,200 = 3,369 meters per second squared. 3.369 kps is therefore the orbital velocity at 378 km altitude. Multiply by the square root of 2 to get the escape velocity of 4.764 kps. So that's an additional 1.385 kps needed to escape the gravity of mars once it's in orbit at an… [cont.] Answered by eelfins - Sat Mar 29 06:38:26 2008 From Yahoo Answer Search: "spacecraft propulsion" |
