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[–] 60 points 1 year ago (3 children)

NASA: We’ve been getting a lot of footage of you being cringy in high school.

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  • [–] 92 points 1 year ago (22 children)

    But only after 10 years. You couldn't see anything that wasn't visible from the viewpoint of the mirror beforehand, as from earth's point of view the mirror isn't there yet. And if you're there anyway… you can just look at Earth with the craft that's on the position of the mirror already.

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  • [–] 42 points 1 year ago* (13 children)

    That's why we need to find a natural mirror somewhere already out there, so we can see into our past. Something like a planet made of pure mercury, or an arrangement of blackholes doing gravitational lensing that bends our light back to us, or whatever. We'd also need instruments vastly superior than what we currently have in order to get any useful information out of seeing our own light bounced back to us from so far away

    ... But still! the idea that it's at least hypothetically possible to actually see our own past is very exciting!

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  • [–] 19 points 1 year ago (8 children)

    Just look in any mirror. What you see is also you in the past.

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  • [–] 24 points 1 year ago (3 children)

    “‘That’s a picture of me when I was younger.’ Yeah, no shit. Every picture of you is a picture of you when you were younger.”

    -Mitch Hedberg

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  • [–] 18 points 1 year ago (2 children)

    He didn't curse in that line. In fact he didn't curse much generally. I don't have any objection to curse words, it just doesn't sound like his voice when you add curse words in.

    Fuck shit ass titties. I just had to get that out after talking about not cursing

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  • [–] 7 points 1 year ago (1 child)

    I'm assuming the inverse square law would hinder us from seeing anything useful. But now I'm imagining scientists being ecstatic about discovering a foreign signal, only to realise its us from the past

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  • [–] 7 points 1 year ago

    That's highly unlikely basically because of the inverse square law. Even tightly focused beams dissipate quite effectively over light-hours, let alone light years. We'd be lucky to catch a single photon from our past selves over any significant distance.

    For reference, look up how weak the signal is even just coming back from the moon when people try to hit the retroreflectors with lasers. Or how crazy weak the signals are when they reach Voyager.

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  • [–] 5 points 1 year ago (3 children)

    Only after 20 years. Light will take 10y to make it from earth to the mirror, and 10y to travel back.

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    [–] 23 points 1 year ago (2 children)

    You can already do this with the light bent around black holes, it's just a bit hard to make out the image... make sure you wipe down your black hole with a damp cloth, you don't want a smudgey black hole

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  • [–] 16 points 1 year ago (1 child)

    and if you look through the butt end of the telescope, you can see in the future

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  • [–] 12 points 1 year ago* (14 children)

    It'd actually be cool as fuck if we could make some kind of Paycheck-style time machine that lets you see into the past by simply looking at light reflected off other celestial objects.

    It could theoretically work looking backwards, but not forwards as it was used in the film. Of course, it'd have to have insane resolution for it to be like a video of what happened on the planet and not just a dot of light.

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  • [–] 13 points 1 year ago (4 children)

    time machine that lets you see into the past by simply looking at light

    You mean, this ?

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  • [–] 5 points 1 year ago (2 children)

    lol

    Real time, tho. That way we can see photographs from before cameras, too. Watch what dinosaurs were doing n stuff.

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  • [+] 5 points 1 year ago (7 children)
  • [–] 4 points 1 year ago (4 children)

    But that's boring, doing it with light is way better.

    Also the governments already do that and don't want to share.

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  • [+] 1 point 1 year ago (3 children)
  • [–] 2 points 1 year ago* (2 children)

    I can get nostalgia looking at my previous address on Maps because it shows my old Jetta (my first car) in the driveway :D

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  • [–] 11 points 1 year ago

    You may need to squint a little.

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  • [–] 4 points 1 year ago (1 child)

    If you did this quickly with a warp drive or whatever, you would still need at least ten years to see the results, so you could only see as far back as when you put the mirror up at the most.

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  • [–] 7 points 1 year ago

    No, you can see 20 years into the past, but only in 10 years. If you managed to will it into existence now, the light that left us 10 years ago would arrive at the mirror now and start heading back. That light would hit earth 10 years from now, so in 2035 we'd be able to see 2015

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  • [–] 5 points 1 year ago

    Big brother called, you weren’t supposed to leak this hack.

    If only they did work into the future then they could have stopped you from spilling the beans.

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  • [–] 3 points 1 year ago (1 child)

    Yeah, but it'd take us strictly longer than N years to place a mirror N light years away form Earth, so kinda useless.

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  • [–] 5 points 1 year ago

    It would be neat to record the mirror as it was going.

    Ignoring physics of moving a mirror near the SoL, having a recording of it would both be cool to watch and would help confirm on a macro level the effects of speed-related dilation.

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  • [–] 0 points 1 year ago (3 children)

    Or youd see 20 years into the future... Let that one bake your noodle for a spell...

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  • [–] 1 point 1 year ago* (1 child)

    No you always see into the past.

    Light cannot travel back in time. The reflection you’d see in the mirror is the light that left the Earth 20 years ago.

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  • The mirror always looks back... (insert annoying spooky laugh)

    But, just to be less of a Halloween spookster. The mirror is placed in a rather exotic location in space, and between the mirror and the Earth is... wait for it... youre going to hate this lol... a naturally occurring closed timelike curve! See, I told you youd hate it lol.

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