• phdepressed@sh.itjust.works
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        16 days ago

        My brother, that explanation is not nearly dumbed down enough and as with most math wiki is useless for eli5 stuff.

        • mkwt@lemmy.world
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          16 days ago

          I think a lot of people understand the concept of light-seconds, which can measure distance in seconds.

          Allow me to introduce the gravity-second. 1 gravity-second of mass-energy is enough mass-energy to have a Schwarzchild radius of 2 light-seconds.

            • davidgro@lemmy.world
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              16 days ago

              Size of a black hole.

              Certain mass = certain distance

              Distance = seconds

              Therefore mass = seconds

              • uis@lemm.ee
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                16 days ago

                Then I don’t even want to be in same solar system with millisecond heavy object.

                • davidgro@lemmy.world
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                  16 days ago

                  You most certainly don’t, that’s a radius of about 300km (186 miles) and a mass of 101 suns.

                  Even if you meant microsecond, that’s 1/10 of the sun, and would be very disruptive.

    • sleen@lemmy.zip
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      16 days ago

      You don’t want to know what an astrophysicist does in their free time.

      • ArbitraryValue@sh.itjust.works
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        16 days ago

        Well the one I knew spent his free time doing community theater, having many of the women there go crazy over him (he was good-looking and charming), and then not sleeping with any of them because he was a wait-until-marriage religious guy. I don’t think he was typical.

        • cafeinux@infosec.pub
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          16 days ago

          I intended to be an astrophysicist before finally settling on IT, and I was doing theater before life did its things and I had to stop. I’m kinda religious but not THAT religious (and my SO is an atheist so, really not THAT much).

          Maybe there’s kind of a type anyway.

  • BarqsHasBite@lemmy.world
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    16 days ago

    Fun fact: Seconds are called seconds because the first breakdown of an hour is the minute, and the second breakdown is the second. Don’t ask me the obvious question(s) because I don’t know.

    • f314@lemmy.world
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      16 days ago

      If by obvious question you mean “why is it called a minute,” that is because “minute” means “small.” So you have the first minute (small) part and the second minute part of the hour.

  • uis@lemm.ee
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    16 days ago

    Mass in seconds? How? I get mass in Joules, but seconds?

    • Eiri@lemmy.ca
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      16 days ago

      There are two possibilities I can think of:

      • Orbit duration can be used to calculate mass
      • The diameter of a star or the parallax distance on the sky (in arcseconds) can also be used to evaluate mass
        • Eiri@lemmy.ca
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          13 days ago

          I thought stars of similar masses were also of similar sizes. They’re not?

          • Lifter@discuss.tchncs.de
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            12 days ago

            I’m no astrologer but from what I’ve learned, we also need to look at the color to glassify stars into categories. It varies a bit though in each category so it’s a blunt tool.

            Then there are other objects like gas clouds and even galaxies. For those, we have no idea of the density distribution, so radial size gives us even less info.

  • IndiBrony@lemmy.world
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    16 days ago

    Me: not smart enough to understand

    Brain: Quick! Say something to sound like you fit in!

    Me: uh … I just did the Kessel Run in under 12 parsecs!

  • drail@fedia.io
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    16 days ago

    Everything should just be in eV. Particle physics natural units are the best.

  • observantTrapezium@lemmy.ca
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    16 days ago

    That may be relativists (they would actually measure anything in units of mass, with everything else defined through G = c = 1). Astrophysicists commonly measure mass in solar masses, long distances in parsec (or kiloparsec, megaparsec), short distances in solar radii or AU, and time in whatever is relevant to their problem (could be seconds or gigayears)

    • Sconrad122@lemmy.world
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      16 days ago

      short distances in solar radii

      I think astrophycisists and I may have a difference of opinion on the meaning of the adjective short

  • montechristo@feddit.org
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    16 days ago

    If you ever find yourself among theoretical physicists and/or astrophysicists and need a conversation starter, just ask about unit systems or unitless/natural measurement systems. There is no other profession that is more obsessed about that topic.

    Just to put this here:

    ħ=1

      • m0darn@lemmy.ca
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        15 days ago

        Yeah true, but I think they actually use wavelength of red shift, which is distance… traveled by light in the time it takes to make a full cycle. So I guess we’re back to seconds again.

        I think they use this for distance and time because at scales being dealt with they have the same implications.

      • m0darn@lemmy.ca
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        15 days ago

        I think you need to be more specific than ‘long distance’, yes they use parsecs for ‘long distances’ but I believe only for intra-galactic objects. I think other galaxies are too distant for parallax seconds to be useful.