6 ms·

ELI5 please

• Cthulhu_ 6y ago
  Two satellites are on a head-on trajectory to crash into one another, chances of impact are between 1 and 20%.
  • csunbird 6y ago
    At least that they are not on reverse/opposite orbits, hopefully one of the orbits will shift after this event and the intersection would be a non-issue. If none of the orbits decay, the intersection is extremely likely to happen again, with a similar result. Edit: I am mistaken, they are on reverse/opposite orbits, which is actually a huge problem!
• threatripper 6y ago
  * Satellites are kept in orbit by gravity. * They fly around earth in circular or elliptical orbits. * These satellites are at 900 km height. That is 100 times higher than the highest mountain on earth. * Up there is still a tiny bit of air which makes slower and slower. But at that height it takes 1000 years until they fall back down to earth. That is more than 10 times the life span of a human. * We have many satellites and leftover parts of rockets up there in space. But space is also big, so there is rarely the danger of a collision. Most big parts move on paths where they don't hit each other. * When these two satellites hit each other they will break apart into thousands of small pieces. The satellites fly very fast and the small pieces will be faster than a bullet. * Some of the small pieces fall back to earth where they will burn in the atmosphere. Other pieces fly away in all directions. Some pieces as tiny as a bullet will hit other satellites and destroy them. Some bigger pieces will rip apart other satellites creating more bullets. * There is the danger that many satellites are destroyed and millions of small pieces fly around in space. * When you launch a rocket you must pass through this area with a high danger of being hit by one of the bullets which would destroy the rocket and create more bullets. * We might have to wait until most of the dangerous debris has fallen back to earth until we can launch rockets again. This could take hundreds of years. * If we don't clean up space and put more and more waste in orbit we will never be able to leave earth and explore deep space. * Good night and sleep tight.
  • pferde 6y ago
    How does a five year old know what a "satellite", "gravity", "orbit", or half a dozen of other words used here is? The "ELI5" meme needs to die, it does not make any sense in most of the situations it is used, and also it's a self-disgrace to anyone using it to compare their own intelligence and knowledge to that of a five year old.
    • zowanet 6y ago
      I wouldn't say it's a meme, it's just a convenient shorthand for "I'm not overly familiar with the domain, please help me understand". No need to overthink it.
      • pferde 6y ago
        I would say it is indeed a meme. From Wikipedia: "A meme is an idea, behavior, or style that becomes a fad and spreads by means of imitation from person to person within a culture and often carries symbolic meaning representing a particular phenomenon or theme." Contrary to what Internet would like us to believe, a " meme" is not a picture of a cat with some written words around it.
        • cbg0 6y ago
          You're being overly pedantic about this thing.
          • pferde 6y ago
            What, pedantic about correct terms describing correct things? If we cease to care about that, any communication using words simply stops working, because orange breathe knit, attend evasive colour and lonely arrogant arithmetic chemical wonder twig.
      • JshWright 6y ago
        It's definitely a meme, but that doesn't mean it isn't useful in the sense you describe.