In my mid-forties, I believe I have seen Pluto for the first time with the naked eye

  • Early this morning going out on the balcony, I looked up on a star chart app to verify it was Jupiter I was seeing. Then I noticed the alignment of Mars, Saturn, and Pluto on the app.

    Never being able to identify it before, I stared at where Pluto should be and I'm pretty sure I saw it.

    My only question is - since it's said that planets shine and stars twinkle, it did seem that Pluto was flicking a bit. Is this normal? Something to do with the relatively low luminosity and greater length of space?

    It wouldn't have been Pluto, it's far too small and faint to be seen without a really powerful telescope. It was most likely a star that just happened to be in roughly the same place.

    I agree with the previous statement. There's absolutely no chance to see Pluto with your naked eye. One can't even see objects of Plutos size in the asteroid belt (which is much closer) with the naked eye.

    Thanks for setting me straight. Good thing I didn't go into the real world bragging yet.

    Pluto is so small that it fails to fully occult stars. That's small enough to twinkle. But I still think you fooled yourself.

    If Pluto was visible to the naked eye, it would have been known since antiquity. But it was not, neither were Uranus or Neptune which are closer, larger, and brighter.

    It was probably a UFO. Source: Seen one too ;)

    Marvin, maybe ? EDIT: sorry, he's from Mars

    Some asteroids are sometimes naked-eye visible, but they're unlikely to be on your chart, so I reckon there's a small chance it was one of those.

    On planets twinkling: "why does venus flick?"

  • Pluto is something like magnitude 14. The limit for the human vision is somewhere between magnitude 6 (widely accepted) and 8-ish (highly trained observers with perfect vision in ideal conditions using special techniques - and it's a bit controversial anyway).

    There's zero chance that was Pluto. It was definitely a fixed star.

    The difference is somewhere between 250 to 1000. It means, it is not a little bit fainter to be visible, it should be 1000 times lighter to be visible like a very faint star.

    It surely wasn't Pluto indeed. You cannot be sure it was a star though (e.g. satellite, plane, ...)

    But a plane must move faster on the sky than a planet, does it not?

    @mathreadler: Planes that are far away but flying in your exact direction can be surprisingly bright and stable in the sky.

    Since when are stars "fixed"? ;-)

    Obviously stars are fixed, or they'd all come crashing down on us.

    @uhoh "Fixed star" is a commonly used term in astronomy, although nowadays it's more of a historic interest, since we now understand that most star-like objects visible with the naked eye, which appear to be unmoving relative to each other, are indeed stars. Even so, it's still in use, so don't be surprised when you hear it.

    @FlorinAndrei Since it has a latin equivalent (e.g. Wikipedia's reference to *stellae fixae*) it's officially "a thing". I always enjoy your substantial and authoritative answers btw!

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Content dated before 7/24/2021 11:53 AM

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