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Spacecraft flew hundreds of thousands to hundreds of millions of kilometers from the earth, injecting speed when the size and direction of a slight error, arrived at target planets will appear large deviation error, for example, when Mars probe injecting speed 1 m/s speed (about one over ten thousand), arrived at Mars, about 100000 km distance deviation. Therefore, precise control and navigation must be carried out during the long flight. Flying to the moon is usually controlled by the orbital control system of the ground and space probe (see orbit control). Interplanetary flight distances, radio signal transmission time is long, the real-time remote control, can't so planets and interplanetary spacecraft orbit control system shall have the ability of autonomous navigation (see interstellar travel navigation and control). The United States, for example, "pirates" spacecraft in space flight of more than eight hundred million km, for 11 months of 2000 times of autonomous orbit adjustment, the final surface to achieve a soft landing on Mars, placement accuracy up to 50 km. In addition, in order to ensure the accuracy of the orbit control engine, the communication antenna is always aimed at the earth, and other systems work normally, and the detector has the autonomous attitude control ability
Sport is considered one of the most entertainment sources that interest countless fans with dramatic matches or attractive performances. In the time being, Champions League will be the main interest of all football fans on the globe. The 2010–2011 UEFA Champions League counts for the 56th season of the premier European club football tournament. 76 teams from 52 UEFA associations have participated in the champion. The final match will take place at Wembley Stadium in London on 28 May 2011. This year season experiences many breathtaking victories and memorable moments. Let\'s enjoy the reigning champion with the following photos.
Whenever your freezer prevents running, look at the condenser coils across the back end of your carton. Ensure that area of is numerous inches past the wall structure. Not a thing need to be at the pinnacle as well as the tailgate end, that can prevent the high temperature forthcoming away, from the coils.
Today, the methodologies have changed, but, the necessity has not; businesses still need new customers and clients to achieve success. Since a growing number of company is conducted online everyday, competition becomes tougher.? Businesses must differentiate yourself from their competitors.? Our objective is usually to enable you to reach that goal result.
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