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It always seems to involve mastering gravity yet gravity is so incredibly weak compared to magnetism. Plus "alien spacecraft" aka UFOs always seem to output a h

It always seems to involve mastering gravity yet gravity is so incredibly weak compared to magnetism. Plus "alien spacecraft" aka UFOs always seem to output a huge amount of light so maybe gravity and light are linked in the process or mechanism for whatever makes the thing operate. I like the article how it mentions getting the science believable or at least not terrible wrong. But what I dislike as much as that is whenever the science parts are dismissed. Usually a scientist in a movie or TV show tries to explain something the lead character rolls their eyes as if it were boring everyone laughs. How can we encourage kids that science is interesting if it's treated as a bore or a joke and ridiculed? I know it's meant as a writing method to make the lead person seem dumb compared to the smart scientist but it sends a bad message that science is boring.

foota 10y ago
Perhaps it's because gravity is relatively less well understood than is magnetism?
jandrese 10y ago
Using gravity as a propulsive force may be silly given its relative strength, but having a way of blocking gravity would make a tremendous difference in getting out of our gravity well. It's not so much help for achieving orbit, but if you want to go beyond the Earth or even beyond the Solar System it would be a whole new game.
- avar 10y ago
  If you can block gravity you can achieve orbit at walking speeds if you turn of your anti-gravity machine some tiny fraction of the time you're spending in orbit. Similarly with going outside the solar system, you could just jump on the planet Earth and press the "anti-grav" button, and in a few hundred thousand years you'd be outside the solar system.
  - jws 10y ago
    I think you can dispense with the "jump". Just press the "gravity off" switch at midnight. You will be on the far side of the earth from the sun, as the earth is pulled to the sun in its orbit, you will drift away on a tangent line at 30km/s relative to the sun. Google says "9 billion miles divided by 30km/s" is a little over 15 years and you are out of the solar system. (I'm ignoring the milky way here, The sun is whizzing around the milky way at 230km/s, but it isn't very near the center so the "chord near the center is simplified to radius" which I snuck by you in the previous paragraph isn't valid. But you should definitely work this out before flicking the switch. Depending on the relative gravity/velocity magnitudes and the time of year, you could drive yourself through the sun on your way out of the solar system, which voids your warrantee.)
    - avar 10y ago
      Thanks, I didn't do any of the math, but I should have remembered better from this counteractive fact: You're already at 30km/s, it takes more energy to fall into the Sun than escape the Solar System. Even if you press the "gravity off" button at some random time during the day the odds of you hitting anything are tiny, even if you fly towards the sun most of the time you'll just fly right past it and be no worse off. Except for the part where there's no oxygen and you can't breathe of course.
      - spynxic 10y ago
        "gravity off" is a lofty term to toss around so freely. Consider an omnipresent force or curvature vanishing one spot. I can't imagine gravity but the effects in an ocean would obviously be to fill the hole with massive force.
  - jandrese 10y ago
    Orbit isn't about getting 160km over the surface of the Earth, it's about accelerating to 7.8km/s so you don't fall back down to Earth. Your anti-gravity pump won't help you in that regard. Getting to orbit isn't hard because you have to go so high, it's hard because you have to go so fast.
- nerfhammer 10y ago
  Gravity is just spacetime curvature. You can "turn off" gravity by just accelerating in the opposite direction at 1g.
Someone 10y ago
The problem with magnetism is that we do not know how to make a magnetic monopole (if it is possible at all), let alone a powerful one.
booleandilemma 10y ago
There's a short story by Harry Turtledove about aliens that have mastered gravity (because, as it turns out, it isn't that difficult to do) but all of their other technology is pre-industrial revolution level. They try to invade Earth in 2039 - I won't spoil what happens next. It's a fun read. https://en.m.wikipedia.org/wiki/The_Road_Not_Taken_(short_story) https://en.m.wikipedia.org/wiki/The_Road_Not_Taken_(short_st...
- andrewflnr 10y ago
  I loved that story, but couldn't remember what it was called. Thanks!
rl3 10y ago
>Plus "alien spacecraft" aka UFOs always seem to output a huge amount of light ... That aspect in particular is interesting because it's central to most UFO sightings, and subsequently adds to the collective mythology. For the sake of argument, imagine you operate a joint USAF/CIA psyops program charged with protecting the secrecy of entirely-terrestrial aerospace black programs. Personally, the first thing I'd do is take existing airframes, coat them in a matte or even light-absorbing material, put a blindingly-bright layer of lights on top of that, and conduct missions at night, in a profile that minimizes noise. The lights serve to draw attention, conceal the airframe's actual shape, and suggest some extraterrestrial origin all at the same time. At the risk of sounding like a nutter spouting the usual "black helicopters" cliché, it's worth noting that during the Vietnam War, the US operated a modified Hughes 500-series helicopter reconfigured for extremely quiet operation.[0] Likewise, Bin Laden's compound in Abbottabad was raided in 2011 using stealth helicopters. During interviews, neighbors present at the time of the raid said they weren't able to hear the aircraft until they were almost directly overhead.[1] Compared to a normal helicopter, that's extremely quiet. The Phoenix Lights[2] was a very famous UFO sighting, and in my opinion was almost certainly man-made. The technology was there to build long-endurance unmanned VTOL aircraft at the time, especially when all you need is some struts, lights, a control system, maybe a balloon, and some propulsion. Complexity comparable to what hobbyists face when building small quadcopter drones today, just scaled up in size. At further risk of sounding like a complete nutter, I think it's probable that the rash of cattle mutilations[3] throughout the United States were a result of something similar. If you're already tooling around with quiet aircraft lit up like Christmas trees, dissecting cattle in the process for whatever legitimate ancillary reason will only further solidify the belief it's aliens. The bright light we often associate with UFOs is likely just a terrestrial invention. [0] https://en.wikipedia.org/wiki/Hughes_OH-6_Cayuse#.22The_Quiet_One.22 https://en.wikipedia.org/wiki/Hughes_OH-6_Cayuse#.22The_Quie... [1] http://abcnews.go.com/Blotter/top-secret-stealth-helicopter-program-revealed-osama-bin/story?id=13530693 http://abcnews.go.com/Blotter/top-secret-stealth-helicopter-... [2] https://en.wikipedia.org/wiki/Phoenix_Lights https://en.wikipedia.org/wiki/Phoenix_Lights [3] https://en.wikipedia.org/wiki/Cattle_mutilation#Government_or_military_experimentation https://en.wikipedia.org/wiki/Cattle_mutilation#Government_o...

foota 10y ago

Perhaps it's because gravity is relatively less well understood than is magnetism?

jandrese 10y ago

Using gravity as a propulsive force may be silly given its relative strength, but having a way of blocking gravity would make a tremendous difference in getting out of our gravity well. It's not so much help for achieving orbit, but if you want to go beyond the Earth or even beyond the Solar System it would be a whole new game.

avar 10y ago
If you can block gravity you can achieve orbit at walking speeds if you turn of your anti-gravity machine some tiny fraction of the time you're spending in orbit. Similarly with going outside the solar system, you could just jump on the planet Earth and press the "anti-grav" button, and in a few hundred thousand years you'd be outside the solar system.
- jws 10y ago
  I think you can dispense with the "jump". Just press the "gravity off" switch at midnight. You will be on the far side of the earth from the sun, as the earth is pulled to the sun in its orbit, you will drift away on a tangent line at 30km/s relative to the sun. Google says "9 billion miles divided by 30km/s" is a little over 15 years and you are out of the solar system. (I'm ignoring the milky way here, The sun is whizzing around the milky way at 230km/s, but it isn't very near the center so the "chord near the center is simplified to radius" which I snuck by you in the previous paragraph isn't valid. But you should definitely work this out before flicking the switch. Depending on the relative gravity/velocity magnitudes and the time of year, you could drive yourself through the sun on your way out of the solar system, which voids your warrantee.)
  - avar 10y ago
    Thanks, I didn't do any of the math, but I should have remembered better from this counteractive fact: You're already at 30km/s, it takes more energy to fall into the Sun than escape the Solar System. Even if you press the "gravity off" button at some random time during the day the odds of you hitting anything are tiny, even if you fly towards the sun most of the time you'll just fly right past it and be no worse off. Except for the part where there's no oxygen and you can't breathe of course.
    - spynxic 10y ago
      "gravity off" is a lofty term to toss around so freely. Consider an omnipresent force or curvature vanishing one spot. I can't imagine gravity but the effects in an ocean would obviously be to fill the hole with massive force.
- jandrese 10y ago
  Orbit isn't about getting 160km over the surface of the Earth, it's about accelerating to 7.8km/s so you don't fall back down to Earth. Your anti-gravity pump won't help you in that regard. Getting to orbit isn't hard because you have to go so high, it's hard because you have to go so fast.
nerfhammer 10y ago
Gravity is just spacetime curvature. You can "turn off" gravity by just accelerating in the opposite direction at 1g.

Someone 10y ago

The problem with magnetism is that we do not know how to make a magnetic monopole (if it is possible at all), let alone a powerful one.

booleandilemma 10y ago

There's a short story by Harry Turtledove about aliens that have mastered gravity (because, as it turns out, it isn't that difficult to do) but all of their other technology is pre-industrial revolution level. They try to invade Earth in 2039 - I won't spoil what happens next. It's a fun read. https://en.m.wikipedia.org/wiki/The_Road_Not_Taken_(short_story) https://en.m.wikipedia.org/wiki/The_Road_Not_Taken_(short_st...

andrewflnr 10y ago
I loved that story, but couldn't remember what it was called. Thanks!

rl3 10y ago

>Plus "alien spacecraft" aka UFOs always seem to output a huge amount of light ... That aspect in particular is interesting because it's central to most UFO sightings, and subsequently adds to the collective mythology. For the sake of argument, imagine you operate a joint USAF/CIA psyops program charged with protecting the secrecy of entirely-terrestrial aerospace black programs. Personally, the first thing I'd do is take existing airframes, coat them in a matte or even light-absorbing material, put a blindingly-bright layer of lights on top of that, and conduct missions at night, in a profile that minimizes noise. The lights serve to draw attention, conceal the airframe's actual shape, and suggest some extraterrestrial origin all at the same time. At the risk of sounding like a nutter spouting the usual "black helicopters" cliché, it's worth noting that during the Vietnam War, the US operated a modified Hughes 500-series helicopter reconfigured for extremely quiet operation.[0] Likewise, Bin Laden's compound in Abbottabad was raided in 2011 using stealth helicopters. During interviews, neighbors present at the time of the raid said they weren't able to hear the aircraft until they were almost directly overhead.[1] Compared to a normal helicopter, that's extremely quiet. The Phoenix Lights[2] was a very famous UFO sighting, and in my opinion was almost certainly man-made. The technology was there to build long-endurance unmanned VTOL aircraft at the time, especially when all you need is some struts, lights, a control system, maybe a balloon, and some propulsion. Complexity comparable to what hobbyists face when building small quadcopter drones today, just scaled up in size. At further risk of sounding like a complete nutter, I think it's probable that the rash of cattle mutilations[3] throughout the United States were a result of something similar. If you're already tooling around with quiet aircraft lit up like Christmas trees, dissecting cattle in the process for whatever legitimate ancillary reason will only further solidify the belief it's aliens. The bright light we often associate with UFOs is likely just a terrestrial invention. [0] https://en.wikipedia.org/wiki/Hughes_OH-6_Cayuse#.22The_Quiet_One.22 https://en.wikipedia.org/wiki/Hughes_OH-6_Cayuse#.22The_Quie... [1] http://abcnews.go.com/Blotter/top-secret-stealth-helicopter-program-revealed-osama-bin/story?id=13530693 http://abcnews.go.com/Blotter/top-secret-stealth-helicopter-... [2] https://en.wikipedia.org/wiki/Phoenix_Lights https://en.wikipedia.org/wiki/Phoenix_Lights [3] https://en.wikipedia.org/wiki/Cattle_mutilation#Government_or_military_experimentation https://en.wikipedia.org/wiki/Cattle_mutilation#Government_o...