When space shuttles come back to earth how do they know where to land?

At what speed do they pass the earths atmosphere? Does it turn on fire because of the friction?

9 Answers

  • Anonymous
    1 decade ago
    Best Answer

    Computers calculate pretty much everthing on board the space shuttle. A display on board the space shuttle will show a map and the trace of the shuttle's orbit. After every orbit this orbital line shifts and the computer calculates just when the right time is to do a retroburn. For a retroburn, the space shuttle turns opposite to the direction it is moving in and fires its main engines just enough to slow it down to where its orbit intersects the upper layers of the earth's atmosphere at just the right time for a true trajectory towards Cape Canaveral.

    When the shuttle hits the earth's upper atmoshpere at just the right angle (too shallow and it will bounce off back into space, too steep and it will burn up), the shuttle's heat shield will get very hot because of all the friction of the atmosphere. Keep in mind that the shuttle is moving at about 6 miles per second through the upper atmosphere. That is a LOT of friction. The friction, however, serves to slow the shuttle down without having to burn more fuel.

    Once the shuttle reaches a reasonable airspeed, the pilot on board can control it just like an aircraft. As the pilot turns the shuttle, the shuttle's trajectory is displayed on the shuttle's computer screen on top of a computer-drawn map. All the pilot has to do is fly the shuttle towards Florida.

    Onboard computers and guidance systems, and radio communications, make sure that the shuttle pilot reaches the intended landing stip at the Kennedy Space Center, Cape Canaveral, Florida. The shuttle is not as aerodynamic as a normal jetliner, so its descent to the runway is very steep, and very fast. When the shuttle touches down, parachutes are deployed to slow it down.

  • 1 decade ago

    The shuttle orbits at about 17,500 miles per hour; When it's time to come home, they fire the retro-rockets (the 2 smaller rocket nozzles above the 3 main engines) about an hour before reentry. This slows the ship down so it'll encounter the atmosphere.

    Once it starts contact with the atmosphere, it begins to slow. The speed of the shuttle turns to heat as it plows through the thickening atmosphere. It'll do a series of S-turns to slow further, and then it glides to it's landing - usually in Florida, but sometimes California.

    They have to know where the thing is going to land before they fire the retro-rockets, because that has to be done virtually on the other side of the world from their landing site.

  • 1 decade ago

    The shuttle computers know where they are at all times, because they use GPS signals. When they can't get the GPS signals, they use gyroscopes and accelerometers to figure out how fast they are going and in which direction. And they know that Cape Canaveral is at 28° 33′ 21″ N, 80° 36′ 17″ W.

    They enter the atmosphere at about 17,000 miles per hour. The "fire" is almost all because the air is compressed super fast and hard; a very little bit is from friction.

  • 1 decade ago

    the space shuttle lands at one of three places after a mission: Kennedy Space Centre's Shuttle Landing Facility in Flordia, Edwards Air Force Bace in California, or Whitesands, Mexico. they are guided by GPS and navigation aides to either one of those three landing sites. As the space shuttle descends through the atmosphere it is traveling at a peak rate of 17500 mph, and slowing down constantly because of the atmosphere. When the shuttle first encounters the effects of the atmosphere, you will see flames around it (assuming you can see 400,000 ft in the air above mean sea level) due to the intense heat the friction causes

    Source(s): http://www.nasa.gov/shuttle as well as My own Knowlege
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  • Anonymous
    1 decade ago

    Although speed of reentry is important it is actually the angle that is most important, too steep and the craft will burn up, too shallow and it will bounce off the atmosphere. the shuttle typically begins entry at about Mach 25, approx. 19,000 miles per hour.

    The correct course is sound by the electonics on board the shuttle and at mission control.

    Yes, friction and ionization of atmospheric gases heats up the craft to amazingly high temperatures.

  • Anonymous
    1 decade ago

    They attempt to land in Florida because otherwise the shuttle will have to be lugged there for its next use. If Florida weather absolutely does not permit, they can land elsewhere. But they don't make the decision. That's done by controllers on the ground, based on weather conditions.

  • Gene
    Lv 7
    1 decade ago

    Their guidance computer helps them and yes it gets very hot because the air infront of them gets compressed.

  • Anonymous
    1 decade ago

    They have GPS's...

    Then again it's not a Global positioning system...

    More like PS-Positioning System

  • J
    Lv 4
    1 decade ago

    they have a computer

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