3 ms·

If it were an interstellar kinetic weapon it would not be decelerating, as the goal would be to smash us with as much kinetic energy as possible. :)

• SketchySeaBeast 7y ago
  Oh no, that was a piece of the guidance material, used to redirect the weapon. You wouldn't take a shot from 400 light years without wanting the ability to curve the bullet a bit.
  • api 7y ago
    Well that would explain the Fermi Para... <kaboom> ... ... ...
• jschwartzi 7y ago
  Sorry, it's not a weapon. It's just a molecule designed to hijack self-replication to construct a wormhole generator.
  • plutonorm 7y ago
    So that's space viruses that contain DNA which infects any existing life. Causing the organism to change form into a wormhole generator, which then connects to all the other worm hole generators made by the alien designers? So they can just rock up at a random places because they turned the inhabitants into star gates? That's an awesome idea!
    • jschwartzi 7y ago
      It's the plot for The Expanse.
• cwkoss 7y ago
  How much has human activity altered earth orbit? If an alien civilization 1M years ago saw earth and decided to shoot it for whatever reason, how much error would human activity have added? Seems like it would be tiny, but accuracy from such distances would also be huge, so could be 'enough'?. Come to think of it, the chicxulub impact probably had a larger effect on our orbit than any human activity, and a far-away alien civ would have a hard time predicting impacts at such distance. Would be interesting to make an interstellar warfare game that models the speed of light as a 'fog of war'. Projectiles are accelerated too fast for any control or deceleration systems to survive. Goal is to anticipate where opponents' assets will be in the future and move your assets away from where opponent will anticipate they will be. Could bombard your own planet to alter orbit at a cost to productive capacity. Kind of an orbital shuffleboard.
  • sliken 7y ago
    Chicxulub would be hard to predict, but it was 66M years ago. Presumably anyone sending probes that last even a few 100k years would be smart enough to have advanced sensors and notice if any adjustments are made. Even a very small of energy would correct a distant probe direction to encompass any possible earth position. It will be interesting if the new 'Visitor' is shaped similarly to the previous. Maybe there's a robotic factory a 100 light years away and is turning asteroids into mostly passive sensors and lobbing them at likely looking stars at 100,000 mph to check to see if anything interesting is happening. So the launch would have been 600,000 years ago.