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dungisdangit t1_jdf8py5 wrote

You're on a planet orbiting Sagittarius A btw

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RedshiftWarp t1_jdfda8r wrote

It is bizarre to imagine the geometry of that gravity-well extending all the way out here pockmarked with tiny ones from stars and clusters.

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pmMeAllofIt t1_jdfkd6g wrote

It's not really.Were orbiting the center of mass of the whole galaxy, Sagittarius A* just happens to be near there, but if it was to disappear not much would happen out this far.

Sagittarius A* is about 4 million solar masses, but there's possibly about 65 billion solar masses in other stars, then about a trillion solar masses or more in dark matter. We orbit around the center of mass of all of it, and so does the black hole which only makes up about 0.0004% of the total mass(though it could be located right at the barycenter?idk).

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s1ngular1ty2 t1_jdfkvuz wrote

Not really. Our solar system is not orbiting the black hole. We are orbiting the center of mass of the galaxy, and it's dark matter, not the black hole. The black hole is insignificant as far as orbits of the galaxy are concerned. The dark matter of the galaxy dictates the orbits because it is 5x more massive than all the other matter combined.

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Ape_Togetha_Strong t1_jdfa31f wrote

Yes, there would be time dilation. How much depends on the distance the planet was orbiting. It wouldn't be close to the same amount of time dilation as Miller's planet unless you were somewhere between 1 and 2 meters from the event horizon, which isn't exactly a reasonable orbit for a planet.

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ExtonGuy t1_jdfcowv wrote

Not a dump question at all. Every day, there are about 10,000 people finding out about Sgr A* for the first time. And that's in just the US.

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Anonymous-USA t1_jdfem6r wrote

There is an ergosphere around every black hole that extends past it’s event horizon. Yes, there would be time dilation, but it would become less extreme exponentially with the distance from the center of gravity.

But time is relative so to any observer on that planet, time would tick normal to them. We experience time dilation on Earth moving around the sun, and the gravity well of the sun too, but the time dilation compared to, say, an observer on Uranus is negligible. For example, time elapses on Uranus 59.99999997 seconds for every 1 minute on Earth.

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EarthInteresting9781 OP t1_jdfevlk wrote

So would you age slower on Uranus versus earth. Or would your body age all the same?

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Anonymous-USA t1_jdfgp5l wrote

If you had an identical twin on Earth and Uranus, when the one on Earth reaches 70 yrs old, the twin on Uranus will be 1.1 second younger. Not including the time dilation experienced traveling to Uranus, but let’s say we have a transporter to blink us there.

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Exano t1_jdfuwdz wrote

You will always age the same relative to you.

So, assuming you could live on such a massive world, you turning 30 would take the same amount time as here on Earth, so far as how "long" it feels to you.

However if you were to somehow leave and come to earth, you'd find it "older". So like the twin on Uranus example posted here, if you and your clone were born at the same time, black hole you would be "younger" - although - if your clone was now 60 (to your 30) - you'd have "experienced" half as much time as he has.

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Raging_Skywalker t1_jdj0y9i wrote

So on intergalactic level it would be a strategic time-advance to be as isolated from gravity sources as possible, right? For example a perhabs planet-sized ship with a highly advanced species leaving its galaxy-cluster to avoid encounters with other species

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Anonymous-USA t1_jdjn6pb wrote

What??? I don’t know how you came to that conclusion. The time dilation is basically negligible unless very close to the gravity well, even if there is some residual effect past the event horizon or heliosphere (for a sun). In fact, there may be advantages in energy access closer to a major interstellar object.

So I doubt it would make any difference. Rather, any intergalactic species (even our own) would want to mathematically account for time dilation from both sources — velocity and gravity — when communicating data and positioning. Which we already do ourselves. GPS wouldn’t work without accounting for time dilation. So accounting for it, yes, strategically designing around it, unlikely imo

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ExtonGuy t1_jdfce78 wrote

Unless you're within 30 or 40 million kilometers of Sgr A*, the time dilation isn't going to be much at all. For comparison, the radius of Mercury's orbit is 58 million km.

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OnlyAstronomyFans t1_jdhmyif wrote

Off topic but I had a black cat named A*. Called him Star. My dad is a nerd who taught me to be a nerd.

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KilgoreTroutPfc t1_jdg0e5f wrote

Sure but there probably aren’t any planets that close to it. It’s more likely to happen around stellar black holes not galactic black holes.

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National_Journalist8 t1_jdgzs82 wrote

The possibilities are endless. As for what I know about Sagittarius A. Yes it most likely has a black hole at its center. However, it is a dwarf galaxy. That is being assimilated. By the out bar of the Milky Way. From which our planet resides. Or is it Sagittarius D? I get them confused. However, that's the case. Does the black hole of Sagittarius being assimilated," Become. Runaway attractor ? Or will it be drawn to the Milky Ways Center?

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agaloch2314 t1_jdhbnrs wrote

Just for future reference, the supermassive black hole at the centre of the galaxy is Sagittarius A*, pronounced “Sagittarius A star”. Sagittarius A, without the star, refers to the radio source in its entirety including Sgr A West and Sgr A East.

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EarthInteresting9781 OP t1_jdhi7g0 wrote

But it’s a black hole a collapsed star. Why call it a star still?

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enderxzebulun t1_jdhp9sk wrote

/star/ is pronouncing the * in the name. The asterisk is a convention denoting its relationship to a "parent" object (Sag. A)

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Impressive_Map_4977 t1_jdhz6g8 wrote

Very basically speaking, the gravity from the black hole and the velocity of the orbit around it would result in a *relative* slowing of time by an observer further away.

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cheatme1 t1_jdf8nmv wrote

Well it hasn't happened or been explored or tested in any way but these theories make it seem probable everything slows down around a black hole even time.

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Aquaticulture t1_jdfbfp1 wrote

Time dilation due to gravity has been explored and tested…

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Ivedefected t1_jdfhirh wrote

Even more - GPS satellites experience time dilation relative to Earth (both gravitational and kinetic) which they correct for to provide accurate location data.

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cheatme1 t1_jdfqz6i wrote

Somekindofadult said the same thing but yes still appreciate your fact check also

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SomeKindOfAdult t1_jdflv3u wrote

Time dilation due to gravity wells has been well tested by satellites in Earth's orbit. They aren't as deep in Earth's gravity well and experience less time dilation. It's very tiny, but measurable.

Even more, specific, the orbit of Mercury is affected by time dilation due to how close to the Sun it is in a very noticeable way. This was a real mystery - people speculated there had to be another planet pulling on it, named Vulcan - until Einstein proposed Relativity as the correct answer.

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cheatme1 t1_jdfm2qx wrote

I appreciate this explanation even more you even went into details thanks great fact check

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OnlyAstronomyFans t1_jdhncqb wrote

Not to pick on you, but technically you get time dilation any time you speed up relative to what your speed was previous. I think people have been able to prove this experiment with long-haul commercial flights and fantastically accurate clocks.

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