Ancient Astronaut Theory

Discussion in 'Discussions' started by Ruigi, Jul 2, 2012.

  1. banjo2E

    banjo2E Member

    Fortunately, we've maybe found the Higgs boson, so it's possible that we'll crack zero-point energy within the next century.
     
  2. Aegho

    Aegho Member

    Well, the scientists have come out and said that there is now enough evidence for the existance of the higgs boson to say it is true, we just haven't seen the actual thing, just enough trace evidence to say it's there. They're quite cautious about saying it with absolute conviction, because it could be some other previously unknown particle.

    But to go from there to "we'll make quantum engines in a century" is quite a jump.

    Note that there are already more efficient engines than rockets that might be able to take us to the stars, such as the light sail.
     
  3. DavidB1111

    DavidB1111 Member

    Honestly, nuclear propulsion in a ship is actually much much faster than our current rocket propulsion, however, because of the whole nuclear = evil thing, we'll never really be able to use them. :(

    I'd love to get to Mars in a matter of days, not 6 months. :)
    And Banjo, Zero point energy is way far away.

    Regarding the ancient aliens guy, I think this pic is a good use of the aliens guy. In regards to DC comics restarting their universe. :) entire-dcu-rebooted-aliens-or-superboyprime-punching-reality-could-go-either-way.jpg
     
    OmniNegro likes this.
  4. Aegho

    Aegho Member

    How would that even work? It can't be through ejecting hot stuff out the back because you'd run out of fuel. It can't be mechanical because there's no traction in vacuum.

    The only viable thing I can see is combining it with a light sail, having on-board electrical lasers to push the sail. (Of course there may be more options that I am unaware of, but if so please enlighten me).
     
  5. Haldurson

    Haldurson Member

    BTW, I never stated we would use rockets -- I was being purposefully vague since we are talking about post-humans, meaning that a lifetime would not necessarily be the same as a human lifetime, so how we value time might also be different. Heck we could use slow generation ships, with people in hibernation. Or whatever things we have not imagined yet that may be discovered.

    My point is that if it were easy, we'd know how to do it already. So odds are, if travel to other star systems is doable, it may still be impractical simply because of how difficult it may be. The phrase I used 'stripmining' is simply a way of saying that odds are it would be so incredibly expensive that you MIGHT have to destroy your home in the process of getting somewhere else worth visiting outside of your own solar system. I could be completely wrong, assuming vast increases in our knowledge of physics showing that almost everything we believe about conservation laws, and relativity is false. But you always have to assume that those things are true, up until you have evidence to the contrary.
     
  6. OmniaNigrum

    OmniaNigrum Member

    Was this post a joke? Even with a 100% efficiency solar sail, you would gain zero momentum since you are ejecting the same pressure by the laser itself. :p

    You could point the laser behind you and gain propulsion from it, but an ion drive would be a billion times more potent per megawatt put in.
     
  7. Aegho

    Aegho Member

    Again, ion drives need fuel, and to get us to the nearest star other than the sun, accellerating to and then decellerating from 0.1C would take more fuel than all the matter in the known universe. (One of the problems is that the more fuel you have the more fuel you need, and the larger the craft has to be to contain it, which means needing more fuel).

    But on the sun sail thing, yeah I guess the laser has to be on earth(and if you want to return, you'll need another nuclear powered one you can deposit somewhere at the destination).
     
    OmniNegro likes this.
  8. OmniaNigrum

    OmniaNigrum Member

    I agree on the fact of inadequate matter to convert to energy for propulsion parts. I never contended that.

    I just was wondering about the sail part. But you clarified in a way that makes enough sense for my tastes. :)

    Strange as it sounds, the best means of traveling between stars at current is to stay where we are. Eventually a singularity will pull us and other stars close enough to minimize the expense to reach them. (Pun intended.)
     
  9. Aegho

    Aegho Member

    Well... the andromeda galaxy will collide with the milky way in about 4 billion years, and our sun will die in about 7.6 billion years, so I guess that's sort of true. I also think I read something about NASA calculating that our solar system will likely survive the merger.

    Wether the human race is still around in 4 billion years is a very different can of worms.

    And I'm unsure wether the earth will survive that long even if we don't destroy it ourselves, as I'm not certain about wether any stars too close to us will go nova and strip us of our atmosphere, or any asteroids will hit us and end all life. There's one heading our way and depending on how the next pass goes, it may hit us the time after when it comes back again. Look up the apophis asteroid. The chance is quite small, but it could wipe us out this century. Note: its next pass(when it will likely miss) will be closer to us than the moon, it's going to pass as close as our geosyncronous satelites.
     
    OmniNegro likes this.
  10. Frelus

    Frelus Member

    While I do not believe that a 400m diameter asteroid will make humanity go extinct (Or even set us back too much), wow.
    If it does go down in 2036, I hope that until then, they either find out it does not hit, or find a way to avoid the impact/make it less destructive.
     
  11. DavidB1111

    DavidB1111 Member

    Don't get mad at me, but why would you think that?
    Nuclear propulsion in space is probably one of the quickest ways to travel.
    You basically create a nuclear explosion behind the ship, and the explosion creates a shockwave and it propels the ship forward. It may eat fuel, but it's not like it won't last long enough to go places in the solar system. They would be very small nuclear explosions.
    Yes, we can't use it to travel past Alpha Centauri, due to how far away it is. :)

    The reason we can't do it now is because the crazy people who say "nuclear is evil." and won't let us make them viable.

    They'd cut the travel time to Mars down almost 85% or so. I'm not joking, a trip to Mars would take maybe a week or two at most with one.

    No, it will die in 5 billion years.When it contracts into a white dwarf after becoming a red giant that takes up all the way to Earth's orbit, and blowing off it's atmosphere. The atmosphere explosion might destroy some of the moons in the solar system, I'm not sure how powerful it will be.

    Where did you hear 7.6 billion years?
    The sun is 5 billion years old. It formed only 500 million years before the Earth did.
    Planet creation does not take a very long time after all. :)
    Suns like ours last for 10 billion years.

    For it to last for 7.6 billion years more, it would have to have been born after the Earth was around for 1.6 billion years or so. :)
     
    Kazeto and OmniNegro like this.
  12. OmniaNigrum

    OmniaNigrum Member


    Size is only one variable. The mass and inertia mean far more than size can be guessed to mean. A particle can destroy something the size of a small moon if you could somehow put enough inertia into it. What size was the object that destroyed the dinosaurs? What size was the object that destroyed Tunguska? (Read that link. You will find it enlightening.)

    *Edit* BTW, the Tunguska object was perhaps 100m. It was estimated to be as high as 30 megaton detonation. What could four times that do to the world?

    *Edited Again* Four times that would make a nice crater and mess up a few hundred miles of the world, and probably lower the temperature of the entire Earth by as much as a degree or two. It is even possible that it could knock enough of our atmosphere off to slightly change our orbit. But here is the bigger danger. What if it strikes the moon? It could change it from eventually escaping our gravity to being again attracted to the Earth. In essence, this would be an unsurvivable event. It may take a few dozen generations for the impact to happen, but when it did, the Earth would be impossible to survive upon for hundreds of years.

    And what if the Asteroid/Comet was made of something exotic? Any heavy elements or anything dangerous to us? The impact could be the least of our worries.
     
  13. Aegho

    Aegho Member

    Yeah I was noting that it wouldn't be feasible for interstellar flight, I have no problem with it being used for stellar flight, except that it would create somewhat of a storage problem for used craft that have landed, once out of commission, as well as well somewhat of a health hazard at the "starport".

    Lazy fact checking in this case. You are right of course. I just googled it and picked the first answer. ;)
     
    OmniNegro likes this.
  14. Frelus

    Frelus Member

    Yep, I know W=1/2 m(v times v[how the hell do you do the squared etc. signs again]), and that this would be big. I just did not look up the scale yet. If Tunguska was 30 megaton, assuming the same velocity, this asteroid would make a boom worth ~120 megatons.
    The biggest nuclear bomb ever detonated, the Tsar Bomba, was 50 megatons.
    Brickbuildings 55 km away shattered.
    3rd degree burns could have happened 100 km away (This is less important for the asteroid, though, I think, because it is no nuclear explosion)
    Windows were broken 900 km away.
    The seismic shock that followed the explosion was measurable on its third passage around the earth.
    Man, thats some big shit.
     
    OmniNegro likes this.
  15. Aegho

    Aegho Member

    You can use ^ for power of. I don't know how to make a tiny two appear in the corner either. So v^2.
    There's a hilarious video on youtube debunking creationist theories of the flood, where they point out how much energy would be released and how much that would heat the water, etc.

    a 200x200x200km ice asteroid would release the equivalence of 30 4megaton nukes for every single one of the 6 billion people living on this planet, or about 720 billion megaton.
     
    OmniNegro likes this.
  16. OmniaNigrum

    OmniaNigrum Member

    Please leave that post intact Daynab. The math is solid enough that modern creationists would agree the creationist featured was mistaken. :)
     
  17. Aegho

    Aegho Member

    And also serving 10 years in prison for tax evasion. ;)
     
    OmniNegro likes this.
  18. DavidB1111

    DavidB1111 Member

    No problem.

    Regarding the effects of a 400m asteroid, from 500 miles away. This is if it's solid rock by the way.
    Ejecta:
    The ejecta will arrive approximately 7.27 minutes after the impact.
    At your position there is a fine dusting of ejecta with occasional larger fragments
    Average Ejecta Thickness: 11.7 microns ( = 0.461 thousandths of an inch )
    Mean Fragment Diameter: 158 microns ( = 6.21 thousandths of an inch )

    The air blast will arrive approximately 40.7 minutes after impact.
    Peak Overpressure: 1070 Pa = 0.0107 bars = 0.152 psi
    Max wind velocity: 2.51 m/s = 5.62 mph
    Sound Intensity: 61 dB (Loud as heavy traffic)
    Transient Crater Diameter: 5.11 km ( = 3.18 miles )
    Transient Crater Depth: 1.81 km ( = 1.12 miles )
    Final Crater Diameter: 6.36 km ( = 3.95 miles )
    Final Crater Depth: 516 meters ( = 1690 feet )
    The crater formed is a complex crater.
    The volume of the target melted or vaporized is 0.0865 km3 = 0.0207 miles3
    Roughly half the melt remains in the crater, where its average thickness is 4.21 meters ( = 13.8 feet ).


    Even if it was solid iron, it barely has any difference in effect at 500 miles away.

    At 500 miles away, with a 800 meter diameter asteroid, we get this.
    Transient Crater Diameter: 8.86 km ( = 5.5 miles )
    Transient Crater Depth: 3.13 km ( = 1.94 miles )
    Final Crater Diameter: 11.8 km ( = 7.34 miles )
    Final Crater Depth: 623 meters ( = 2040 feet )
    The crater formed is a complex crater.
    The volume of the target melted or vaporized is 0.719 km3 = 0.172 miles3
    Roughly half the melt remains in the crater, where its average thickness is 11.7 meters ( = 38.3 feet ).

    The ejecta will arrive approximately 7.27 minutes after the impact.
    At your position there is a fine dusting of ejecta with occasional larger fragments
    Average Ejecta Thickness: 105 microns ( = 4.15 thousandths of an inch )
    Mean Fragment Diameter: 298 microns ( = 11.8 thousandths of an inch )
    The air blast will arrive approximately 40.7 minutes after impact.
    Peak Overpressure: 2370 Pa = 0.0237 bars = 0.337 psi
    Max wind velocity: 5.54 m/s = 12.4 mph
    Sound Intensity: 68 dB (Loud as heavy traffic)


    These will hurt us, but it won't ruin the entire planet too badly.

    Oh, by the way, the impact that killed off the dinosaurs left a 100 mile wide crater, caused the atmosphere to ignite, creating a global firestorm, then it caused an ice age, and had an impact force of 200 million megatons. :)

    Oh, and Frelus, the impact of a asteroid creates a lot of thermal energy, which means yes, it can cause 3rd degree burns or outright vaporization of your body. :)
     
    OmniNegro likes this.
  19. Aegho

    Aegho Member

    I just checked up on apophis, it's not as big as I originally thought, one hell of a local problem where it hits though.

    E = ½(2.7x10^10)*30728^2
    E = 12746834784000000000 joules = 3046.566630975 megaton.

    3000 megatons is a pretty heavy hit.
     
    OmniNegro likes this.
  20. DavidB1111

    DavidB1111 Member

    Edit: I fail math. Just ignore this.